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To reduce the commutation loss of the pseudospark switch, we connect a magnetic switch in series to the anode of the pseudospark switch. Herein, the typical discharge process and switching characteristics of a pseudospark switch in series with a magnetic switch are experimentally investigated at a different number of magnetic cores, gas pressures, and applied voltages. The results show that the addition of the magnetic switch extends the duration of the hollow cathode discharge of the pseudospark. Moreover, the rapid increase of the loop current and the fast decrease of the discharge voltage are separated, which is beneficial for reducing the commutation loss. With an increasing number of magnetic cores, the magnetic delay time increases and the commutation loss significantly decreases. However, the trigger delay time hardly changes since the magnetic switch does not affect the development of the pre-breakdown phase. At a fixed applied voltage, the trigger delay, magnetic delay time, and commutation loss decrease with increasing gas pressure. Furthermore, at a fixed gas pressure, the trigger delay of the pseudospark switch in series with a magnetic switch first decreases and then remains unchanged with increasing applied voltage, which is similar to that of a pseudospark switch without a magnetic switch because of the strong enough trigger injection. The magnetic delay time decreases and the commutation loss almost linearly increases with increasing applied voltage.

Used widely in microwave devices and material processing, triggered pseudospark discharge can generate an electron beam, the adjustability of which is affected greatly by the working gas pressure and the applied voltage of the pseudospark discharge. This paper reports the development of an electron-beam source based on a single-gap triggered pseudospark discharge device. Its working performance, as measured by the peak beam current, charge quantity, and pulse width, was studied experimentally, and the results showed that the peak beam current increased initially and then decreased with increasing gas pressure. This was because the beam current was limited by the low plasma density at low pressures, while the electron scattering and ion neutralization during drift decreased the beam current at high pressures. The pulse width of the beam current was consistent with that of the loop current and was determined by the damping coefficient of the discharge circuit. With increasing gas pressure, the pulse width decreased gradually. When the gas pressure was constant, the peak beam current increased significantly with increasing applied voltage because of the enhanced electron-emission current and weakened electron scattering. The charge quantity of the beam current also increased with increasing applied voltage, but the pulse width decreased slightly. Based on the above results, this paper also reports qualitative analysis of the change of the discharge process corresponding to the variation of the electron-beam parameters with gas pressure and applied voltage.

The use of machine vision technology for nondestructive online measurements of cucumber parameters was investigated. This technology was first used to capture images of a cucumber canopy. Next, a segmentation algorithm (excess green minus excess red (ExG-ExR)) was used to extract the cucumber canopy area and image parameters (i.e., coverage ratio, canopy length and canopy width). These parameters were combined with those obtained by manual measurements (i.e., stem height, stem diameter, leaf number, and fruit number) to generate five inversion models for four cucumber growth parameters. The results showed that the ExG-ExR segmentation method yielded a 99.5% contact ratio and a 98.2% recognition rate in the extraction of the cucumber canopy region. The inversion models were validated with new images using the following three different cultivation modes: 4 × 2, 4 × 3 and 4 × 4. The inversion results showed that the coefficients of determination ( R 2 ) between the measured values and inversion values of stem height, stem diameter, leaf number, and fruit number exceeded 0.921, 0.899, 0.95 and 0.908, respectively. Thus, the inversion method can provide nondestructive online measurements of cucumber parameters.

To improve the efficiency and accuracy of water-nutrient mixing, a multi-channel fertigation machine was designed; the hardware includes a programmable logic controller (PLC), a touch system and multi-channel sensors. A sectional forecast control algorithm based on the nutrient dilution model was proposed to control the fertigation machine. When the 100-fold concentrated nutrient solution was diluted by a factor of 20–200, the results showed that the standard deviations of the electrical conductivity (Ec) and the pH for four repeat measurements were 0–0.4 mS cm −1 and 0.057–0.12, respectively; therefore, the performance of the nutrient solution was stable. When the target Ec values were 1.0, 1.5, 2.0, 2.5, 3.0 and 4.0 mS·cm −1 , the variation coefficients relative to the target Ec values for three repeat measurements were 2%, 0.94%, 0.87%, 0.63%, 2.37% and 1.8%, respectively. The multi-channel water-nutrient mix resulting from the sectional forecast control algorithm was precise; the error of the Ec was less than 0.05 mS·cm −1 , which satisfies the requirements of fertigation for soilless cultivation in greenhouses.

The computational fluid dynamics technology is applied as the environmental control model, which can include the greenhouse space. Basic environmental factors are set to be the control objects, the field information is achieved via the division of layers by height, and numerical characteristics of each layer are used to describe the field information. Under the natural ventilation condition, real-time requirements, energy consumption, and distribution difference are selected as index functions. The optimization algorithm of adaptive simulated annealing is used to obtain optimal control outputs. A comparison with full-open ventilation shows that the whole index can be reduced at 44.21% and found that a certain mutual exclusiveness exists between the temperature and velocity field in the optimal course. All the results indicate that the application of CFD model has great advantages to improve the control accuracy of greenhouse.

To firstly accurately overall determine the all components of Compound Danshen Dropping Pills (CDDP) and assess how about the authentic quality is for each bath of samples through a quantified fingerprint that only can qualitatively identified which kind of a herbal or Traditional Chinese Medicine may be. The systematically quantified fingerprint method (SQFM) was employed to identify that the qualities of S4 and S6 were belong to best (grade 1), those of S3, S5, S7, S8 and S9 belong to better (grade 2), those of S2 and S10 belong to good (grade 3), and only S1 falling to fine (grade 4) where those were all with 19 fingerprint peaks. On the basis, the important HPLC dissolution fingerprints (DFPs) of CDDPs were meticulously established to investigate the dynamic process in water, 0.1 mol/L hydrogen chloride (HCl) and 0.5% sodium dodecyl sulphate (SDS), respectively, in which SQFM executed the excellently quantified analyses for the DFPs. During the evaluation, the eighth time points of DFPs were selected as the standards for all dissolving to calculate how high are the macro quantitative similarity ( P m ) of DFPs for the other different time points. Finally in terms of Weibull function, lnln [1/(1- P m )]=-0.5951 x (2)+3.8146 x -4.5195 ( r =0.9974), lnln [1/(1- P m )]=-0.5555 x (2)+3.5814 x -4.6126 ( r =0.9972) were acquired in water and in 0.1 mol/L HCl solution respectively, but without in the SDS solution. In order to specially monitor the dissolution dynamic changes of the important fingerprints to guide the preparation technology and improve their bioavailability, We investigated the four strong peaks of CDDP-DFP and calculated out the fitting equations as follows, lnln [1/(1- A i / A max )]= y , the first one (No.6, Protocatechualdehyde), y =-0.5603 x (2)+3.4516 x -3.8974 ( r =0.9988); the second one (No.19, Salvianolic acid B), y =-1.7127 x (2) +9.6655x-11.947 ( r =0.9897); the third one (No.4, Danshensu), y =-0.4239 x (2)+3.0436 x -3.6276 ( r =0.9985); the forth one (No.17, unkown), y =-0.5019 x (2)+3.3706 x -4.1053 ( r =0.9979), which indicated Salvianolic acid B with a prominent discrepancy from others. The quantified HPLC fingerprint can perfectly both quantitatively reflected the authentic quality of CDDPs and accurately overall quantitatively measure the dissolution dynamic varieties in vitro to provide the important information for bioavailability, in which water is proven to be the best dissolution medium for CDDP whose T 50 =4.1 min (released 50%) and T 90 =8.0 min (released 90%).

Computing similarity is extremely important in modern scientific research such as computational biology and data mining. In this paper, we put forward the concept of quantitative dissimilarity (QDS) and define a series of formulations to measure how similar or dissimilar between two objects are in quality and content for their n -dimentional properties, which is based on a simple mathematical model. Through establishing the HPLC fingerprints (HPLC-FPs) of Flos Lonicerae Japonicae (FLJ) to obtain n -dimentional vectors, in which each peak area serves as an element, the authentical quality control of FLJ were successfully implemented by several QDSs. The presented dissimilarity methods can accurately and quantitativey assess all objects differences in n -dimentional properties.