Two-Layer Predictive Control of a Continuous Biodiesel Transesterification Reactor

A novel two-layer predictive control scheme for a continuous biodiesel transesterification reactor is presented. Based on a validated mechanistic model, the least squares (LS) algorithm is used to identify the finite step response (FSR) process model adapted in the controller. The two-layer predictive control method achieves the steady-state optimal setpoints and resolves the multivariable dynamic control problems synchronously. Simulation results show that the two-layer predictive control strategy leads to a significant improvement of control performance in terms of the optimal set-points tracking and disturbances rejection, as compared to conventional PID controller within a multiloop framework

Broadband Doherty Power Amplifier With Transferable Continuous Mode

In this paper, in-band continuous mode transferring (CMT) method is presented for designing broadband Doherty power amplifier (DPA). Specifically, transferable continuous mode, transferring between class-J continuum to class-F-1 continuum, is introduced into DPA at output back-off (OBO) power level for improving bandwidth and efficiency. For validation, a broadband DPA with operation mode transferring from continuous class-J to continuous class-F-1 is designed, fabricated and measured. Experimental results show the drain efficiencies (DEs) of the fabricated DPA are 46.3%-57.7% and 58.4%-69.1% at 6 dB OBO and peaking power levels over 1.7-2.6 GHz. The saturation power of this DPA is 43.1-45.2 dBm with a gain of 9.1-11.2 dB in the interested band. Furthermore, when the fabricated DPA is stimulated by a 20 MHz wideband signal with a peak-to-average power ratio (PAPR) of 7.05 dB at 2.4 GHz, the measured average power is 36.5 dBm with an average DE of 45.7%, and the measured adjacent channel leakage ratios (ACLRs) are -31.9 dBc and -50.4 dBc before and after DPD technique, respectively

An Improved Edge Structure Weighted Hausdorff Distance for Template Matching

Abstract: Template matching based on a Hausdorff distance (HD) approach become popular for object recognition. In this paper, we present a newly improved edge structure weighted HD (ESW-HD) algorithm for object recognition. We use edge points as the feature of the model, and construct the structure tensor by edge intensity and edge gradient. Then, the HD is weighted by the structure tensors. This work illustrates the ESW-HD algorithm by template edge matching which uses edge points and its edge adjacent structure information to perform the image matching. The experimental results show that the improved HD matching method can achieve a good performance level in terms of matching accuracy, even in a noisy environment when compared with the conventional approaches for object recognition

Treatment of Patellar Lower Pole Fracture with Modified Titanium Cable Tension Band Plus Patellar Tibial Tunnel Steel “8” Reduction Band

Purpose: To determine the efficacy of modified titanium tension band plus patellar tendon tunnel steel 8 “reduction band” versus titanium cable tension band fixation for the treatment of patellar lower pole fracture. Materials and Methods: 58 patients with lower patella fracture were enrolled in this study, including 30 patients treated with modified titanium cable tension band plus patellar tibial tunnel wire “8” tension band internal fixation (modified group), and 28 patients with titanium cable tension band fixation. All patients were followed up for 9∼15 months with an average of 11.6 months. Results: Knee flexion was significantly improved in the modified group than in the titanium cable tension band group (111.33 ± 13 degrees versus 98.21 ± 21.70 degrees, P = 0.004). The fracture healing time showed no significant difference. At the end of the follow-up, the improvement excellent rate was 93.33% in the modified group, and 82.14% in the titanium cable tension band group. Titanium cable tension band internal fixation loosening was found in 2 cases, including 1 case of treatment by two surgeries without loose internal fixation. Conclusions: The modified titanium cable tension band with “8” tension band fixation showed better efficacy for lower patella fractures than titanium cable tension band fixation

Enzymatic regulation of organic acid metabolism in an alkali-tolerant halophyte Chloris virgata during response to salt and alkali stresses

Chloris virgata, an alkali-tolerant halophyte, was chosen as the test material for our research. The seedlings of C. virgata were treated with varying salt and alkali stress. First, the composition and content of organic acids in shoots were analyzed and the results indicated that there was not only a significant increase in total organic acids, but there were also obvious changes in different components of organic acids under alkali stress. The increments in citrate were the largest, followed by malate. However, none of the organic acids showed significant alterations in the content and components under salt stress. Also, activity of some enzymes (citrate synthase, malate synthase, NADP-isocitrate dehydrogenase, and isocitrate lyase) associated with such organic acids did not change significantly under alkali stress, but malate dehydrogenase activity markedly decreased under a stronger alkali stress (80 mM). Under salt stress as well as increased malate synthase (MS) activity, however, there was no significant change for other enzymes. These results strongly demonstrated that the enzymatic regulation of organic acid metabolism may be the biochemical basis of alkali tolerance for C. virgata. Citrate synthase (CS), MS and isocitrate lyase (ICL) might be the key enzymes that determine the alkali tolerance of C. virgata.Keywords: Salinity, ion balance, enzyme activity, Chloris virgat

Simultaneous Determination of 21 Sulfonamides in Poultry Eggs Using Ionic Liquid-Modified Molecularly Imprinted Polymer SPE and UPLC–MS/MS

An ionic liquid-modified molecularly imprinted polymer (IL-MIP) composite with sulfamethazine as a template molecule and methyl acrylic acid and 1-aminopropyl-3-methylimidazolium bromide as functional monomers was successfully synthesized. The achieved IL-MIP was characterized and evaluated in detail and utilized in the extraction and cleanup of sulfonamides (SAs) in poultry egg samples. The results demonstrated that the IL-MIP possessed a broad reorganization toward SAs and could selectively adsorb 21 kinds of SA compounds. Furthermore, the solid-phase extraction column based on the IL-MIP was used in the extraction and cleanup of 21 SAs in eggs, and the confirmatory detection of SAs was performed using ultraperformance liquid chromatography–tandem mass spectrometry. Under optimum conditions, the limits of detection (LODs) for all SAs ranged from 0.1 ng·g−1 to 1.5 ng·g−1, and the LOD of this method was better than those of the existing methods. The recoveries of SA compounds spiked in egg samples ranged from 84.3% to 105.8%, with low relative standard deviations (<15%). The developed method based on the IL-MIP extraction and cleanup was successfully used in the detection of 21 SAs in more than 100 real poultry egg samples. The results indicated that the proposed method was suitable for detecting 21 SAs in poultry eggs

Three-step Reduction Therapy of Integrated Chinese and Western Medicine for Thoracolumbar Burst Fracture

Objective: To investigate and compare the efficacy of three-step reduction (TSR) therapy of integrated Chinese and Western Medicine and posterior open (PO) surgery for thoracolumbar burst fracture. Methods: We selected 60 patients diagnosed with thoracolumbar burst fracture and received treatment in our hospital from December 2014 to March 2017. According to randomized digital table, they were randomly divided into TSR and PO groups. VAS pain grade, Oswestry disability index, height of centrum front, Cobb's angle of spine, bleeding, and complication of internal fixation of the two groups were compared. Results: Postoperative reduction of injured centrum, regained volume of canalis vertebralis, volume of bleeding, and early functional rehabilitation of TSR group were better than that of PO groups (P < 0.05). Conclusion: Through three-step reduction combined pedicle screw fixation surgery, we can achieve satisfied reduction of thoracolumbar burst fracture, rebuild the height of centrum, recover the biomechanics function of spine, and reduce bleeding. Three-step reduction therapy is an effective therapy for thoracolumbar burst fracture

A coverage and obstacle-aware clustering protocol for wireless sensor networks in 3D terrain

In Wireless Sensor Networks (WSNs), clustering techniques are often used to optimize energy consumption and increase Packet Delivery Rate (PDR). To date, most of the proposed clustering protocols assume that there is a Line of Sight (LOS) between all the sensors. In fact, most of the available WSN simulators assume the use of optimistic path loss models that neglect the effect of obstacles on the PDR. However, in real situations such as in 3D terrains, obstacles can interfere this LOS. Moreover, while clustering, it is also important to maintain the coverage of a given Region of Interest (ROI). Therefore, finding an integrated solution for both clustering and coverage problems in an irregular 3D field becomes a pressing concern. In this paper, we first adopt an obstacle-aware path loss model to reflect the effect of obstacles on the communication between any pair of sensors. To that end, the Castalia simulator is adapted to use this proposed path loss model. Then, we introduce a Coverage and Obstacle-Aware Cluster Head Selection (COACHS) protocol to solve the cluster heads selection problem while maintaining a good coverage of a WSN deployed in an irregular 3D field. Simulation results demonstrate that the effect of obstacles on the PDR cannot be neglected. Moreover, comparative evaluation results show that COACHS outperforms other competent protocols in terms of PDR while simultaneously maintaining an acceptable energy consumption and a good coverage of the ROI