GENERATING VIRUS-RESISTANT TRANSGENIC PLANTS HARBOURING ARTIFICIAL MICRORNA CONTAINING COMBINED SEQUENCES FROM TWO ORCHID VIRUSES

Ph.DDOCTOR OF PHILOSOPH

A Fault Location Method Based on Electromagnetic Transient Convolution Considering Frequency-Dependent Parameters and Lossy Ground

As the capacity of power systems grows, the need for quick and precise short-circuit fault location becomes increasingly vital for ensuring the safe and continuous supply of power. In this paper, we propose a fault location method that utilizes electromagnetic transient convolution (EMTC). We assess the performance of a naive EMTC implementation in multi-phase power lines by using frequency-dependent parameters in real fault simulation, while using constant parameters in pre-calculation. Our results show that the location error increases as the distance between the fault location and the measurement location increases. Therefore, we adopt the aerial mode transients after phase-mode transformation to perform the convolution, which reduces the influence of frequency-dependence and ground loss. We conduct numerical experiments in a 3-phase 100-km transmission line, a radial distribution network and IEEE 9-bus system under different fault conditions. Our results show that the proposed method achieves tolerable location errors and operates efficiently through direct convolution of the real fault-generated transient signals and the pre-stored calculated transient signals

Scheduling Performance Evaluation of Logistics Service Supply Chain Based on the Dynamic Index Weight

Scheduling is crucial to the operation of logistics service supply chain (LSSC), so scientific performance evaluation method is required to evaluate the scheduling performance. Different from general project performance evaluation, scheduling activities are usually continuous and multiperiod. Therefore, the weight of scheduling performance evaluation index is not unchanged, but dynamically varied. In this paper, the factors that influence the scheduling performance are analyzed in three levels which are strategic environment, operating process, and scheduling results. Based on these three levels, the scheduling performance evaluation index system of LSSC is established. In all, a new performance evaluation method proposed based on dynamic index weight will have three innovation points. Firstly, a multiphase dynamic interaction method is introduced to improve the quality of quantification. Secondly, due to the large quantity of second-level indexes and the requirements of dynamic weight adjustment, the maximum attribute deviation method is introduced to determine weight of second-level indexes, which can remove the uncertainty of subjective factors. Thirdly, an adjustment coefficient method based on set-valued statistics is introduced to determine the first-level indexes weight. In the end, an application example from a logistics company in China is given to illustrate the effectiveness of the proposed method

Resource recovery from digested manure centrate:Comparison between conventional and aquaporin thin-film composite forward osmosis membranes

We compared the performance of conventional and aquaporin thin-film composite forward osmosis (FO) membranes (denoted as HTI and AQP membrane, respectively) for concentration of digested manure centrate. Results show that the two FO membranes were capable to concentrate digested centrate for resource recovery. During concentration of digested manure centrate, a cohesive fouling layer formed on the HTI membrane surface, resulting in more dramatic flux decline and less fouling reversibility in comparison to the AQP membrane. The two FO membranes exhibited effective and comparable rejection of bulk organic matter, total phosphorus, and heavy metals, leading to their notable enrichment in digested manure centrate. By contrast, ammonium nitrogen (NH4 +-N) was only retained by approximately 40% using the two FO membranes with a slightly higher retention by the HTI membrane, since it was less negatively charged. As a result, total nitrogen was ineffectively rejected by the two FO membranes. It is noteworthy that the HTI membrane also contributed to higher rejection of most antibiotics than the AQP membrane, possibly due to enhanced retention by the fouling layer and retarded forward diffusion. Results from this study evidence the outperformance of the AQP membrane as a new generation FO membrane over its conventional counterpart with respect to antifouling property, while further improvement in membrane selectivity, particularly of monovalent cations (e.g. NH4 +-N), is needed to advance FO applications in resource recovery from challenging waste streams.</p

A Matlab Toolbox for Feature Importance Ranking

More attention is being paid for feature importance ranking (FIR), in particular when thousands of features can be extracted for intelligent diagnosis and personalized medicine. A large number of FIR approaches have been proposed, while few are integrated for comparison and real-life applications. In this study, a matlab toolbox is presented and a total of 30 algorithms are collected. Moreover, the toolbox is evaluated on a database of 163 ultrasound images. To each breast mass lesion, 15 features are extracted. To figure out the optimal subset of features for classification, all combinations of features are tested and linear support vector machine is used for the malignancy prediction of lesions annotated in ultrasound images. At last, the effectiveness of FIR is analyzed according to performance comparison. The toolbox is online (https://github.com/NicoYuCN/matFIR). In our future work, more FIR methods, feature selection methods and machine learning classifiers will be integrated

Effects of surfactant addition to draw solution on the performance of osmotic membrane bioreactor

This study investigated the effects of surfactant addition to the draw solution on the performance of osmotic membrane bioreactor (OMBR). Forward osmosis (FO) tests were conducted with the addition of sodium dodecyl benzene sulfonate (SDBS), a representative surfactant, to both inorganic and ionic organic draw solutions, including sodium chloride (NaCl), sodium acetate (NaOAc), and sodium propionate (NaPro), to determine the desirable draw solution for OMBR operation. Results show that SDBS impacts were more notable for inorganic draw solution in comparison to its ionic organic counterparts at the same osmotic pressure (60 bar) in FO operation. In specific, SDBS addition up to 5 mM considerably reduced the reverse diffusion of NaCl draw solute (approximately 69.7%) with insignificant impact on water flux. Thus, salinity build-up in the bioreactor could be effectively mitigated when SDBS was added to the NaCl draw solution in OMBR operation. This mitigation led to stable sludge characteristics and biological treatment to sustain OMBR performance regarding water production (approximately 10 L/m2h) and contaminant removal (e.g. over 90% for pharmaceutically active compounds).</p

Emerging investigator series:Onsite recycling of saline-alkaline soil washing water by forward osmosis: Techno-economic evaluation and implication

This study investigated the techno-economic feasibility of forward osmosis (FO) for onsite recycling of saline-alkaline soil washing water with an all-purpose liquid fertiliser as a draw solution. Commercially available polyamide thin-film composite and aquaporin FO membranes (denoted HTI and AQP membranes, respectively) were compared under different operating conditions. Results showed that the incorporation of aquaporin vesicles offered the AQP membrane better transport properties (i.e. higher water permeability and lower salt permeability) than the HTI membrane. Thus, the AQP membrane exhibited a much higher water flux and lower reverse solute flux than the HTI membrane in response to either an increase in operating temperature or draw solution concentration. In particular, the water flux of the AQP membrane enhanced from 20.2 to 42.4 L m-2 h-1 with a temperature increase from 25 to 40 °C. Although over 85% water recovery with effective retention of dissolved inorganic salts could be achieved by both FO membranes in concentration of saline-alkaline soil washing water, the AQP membrane was more techno-economically feasible in practice, mainly due to its higher water flux and lower capital and operational expenses. Nevertheless, the economic favourability of the AQP membrane (i.e. the total water cost) over the HTI membrane was largely determined by its membrane element cost. </p