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Currently existing credit risk models, e.g., Scoring Card and Extreme Gradient Boosting (XGBoost), usually have requirements for the capacity of modeling samples. The small sample size may result in the adverse outcomes for the trained models which may neither achieve the expected accuracy nor distinguish risks well. On the other hand, data acquisition can be difficult and restricted due to data protection regulations. In view of the above dilemma, this paper applies Generative Adversarial Nets (GAN) to the construction of small and micro enterprises (SMEs) credit risk model, and proposes a novel training method, namely G-XGBoost, based on the XGBoost model. A few batches of real data are selected to train GAN. When the generative network reaches Nash equilibrium, the network is used to generate pseudo data with the same distribution. The pseudo data is then combined with real data to form an amplified sample set. The amplified sample set is used to train XGBoost for credit risk prediction. The feasibility and advantages of the G-XGBoost model are demonstrated by comparing with the XGBoost model. [ABSTRACT FROM AUTHOR]

Through the introduction of gas-phase monomers phthalic anhydride (PA) and p-phenylenediamine (PPD), replenishment of lubricants during high-temperature friction processes could be realized. According to Fourier transform infrared spectroscopy (FTIR) and gas chromatography–mass spectrometry (GC-MS) analyses, in a 10-min ball–disc friction test at 500 °C, the introduced monomers contacted and polymerized in the gas phase to form solid products with the structure of imides or long carbon chains, which provided superior thermal stability. Solid lubricating films were generated on the disc surface by the physical deposition of these polymerized products and then fall off and attach to the contact position of the ball to form a transfer film. Compared to nonlubricated friction, the coefficient of friction (COF) was reduced from 0.54 to 0.24, and the wear rates of the balls and disc were reduced from 8.32 × 10−6 to 0.65 × 10−6 mm3·N−1·m−1 and from 2.62 × 10−4 to 7.48 × 10−6 mm3·N−1·m−1, respectively. With continued friction but no further introduction of monomers, the solid lubricating film generated in the initial 10 min could provide even more remarkable lubrication for at least the next 15 min, with a minimum COF of 0.01. This could be related to the reinforcing and synergistic lubricating effect of carbonized product powders that gradually formed a continuous phase on the polymerized products' matrix. After the COF increased, low friction could be re-attained by reintroduction monomers, but lubrication would be limited by the previous wear. This novel lubricating film shows potential in high-temperature lubrication, because it has both the effectiveness and stability of solid lubrication and the replenishability of gas lubrication. [ABSTRACT FROM AUTHOR]

In order to recovery whey protein from yak whey wastewater effectively, a facile method of foam separation to be suitable for the local nomadic herdsmen in Qinghai-Tibet Plateau has been established in this research. The effects of the four factors, protein concentration, gas velocity, temperature and pH, on the performance of foam separation were investigated. Based on the single factor experiments, the response surface software was adopted to optimize and to investigate conditions of foam separation for whey protein, and the optimal conditions were found to be protein concentration of 120 μg/mL, gas velocity of 310 mL/min, temperature of 41°C and pH of 3.8, respectively. The as-obtained results of verification experiments, recovery percentage 88.3% and enrichment ratio 9.25 showed that foam separation technique was a simple equipment and environmental compatibility method to separate whey protein from yak whey wastewater. [ABSTRACT FROM AUTHOR]

The study on forecasting demand for online car-hailing holds substantial implications for both online car-hailing platforms and government agencies responsible for traffic management. This research proposes an enhanced Empirical Mode Decomposition Long-short Term Memory Neural Network (EMD-LSTM) model. EMD technique reduces noise and extracts stable intrinsic mode functions (IMF) from the original time series. Genetic algorithm is deployed to improve the K-Means clustering for determining optimal clusters. These sub time series serve as input for the prediction model, with combined results giving final predictions. Experimental data from Didi includes Haikou’s car-hailing orders from May to October 2017 and Beijing’s from January to May 2020. Results show improved EMD-LSTM reduces instability and captures characteristics better. Compared to unmodified EMD-LSTM, RMSE decreases by 3.50%, 6.81%, and 6.81% for the three datasets, and by 30.97%, 20%, and 9.24% respectively compared to single LSTM model. [ABSTRACT FROM AUTHOR]

A novel neodymium(III) complex containing tungstogermanate and 5-fluorouracil, K11(C4H4FN2O2)2Nd(GeW11O39)2·15H2O (FNdGeW), was synthesized and its structure was characterized by 1H NMR, IR, XRD, and TG-DSC. The results indicated that FNdGeW had Keggin structure of hetereopolyanion and structure of 5-fluorouracil. The thermal analysis showed that FNdGeW decomposed at 255.3 °C. MTT tests were performed to study the anticancer activities against SGC-7901 and HepG2 cells. The results showed that FNdGeW and FGeW possessed higher anticancer activities than 5-fluorouracil. FNdGeW exhibited the highest anticancer activities against SGC-7901 cells (IC50 = 0.79 μmol•L-1) and HepG2 cells (IC50 = 0.37 μmol•L-1). [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of electrical stimulation (ES) on the nerve regeneration and functional recovery of facial expression muscles in facial nerve defect rats.Methods: Sixty rats were surgically introduced with a 1-cm defect on the right facial nerves and evenly divided into the Surgery group (Group A, the main trunk of the right facial nerve was surgically cut-off with a 1.0 cm at the foramina stylomastoideum) and the Surgery + ES group (Group B). Twenty normal rats were as normal control group (without receiving surgery or ES). For rats in group B, the orbicularis oris muscle of the right paralyzed face was stimulated with an electrical pulse of 3 V, 20 Hz and 0.3 mA for 1 h each day. The effects of ES on the facial muscle movement, compound muscle action potentials (CMAPs), histological structure, and the expression levels of S100B and NF200 proteins were comparatively studied.Results: In group A, facial paralysis scores were slightly improved from day 1 to 28; the facial nerve trunks had swelled and malformed till day 14; and CMAPs could be induced in fewer animals and were abnormal, resulting in a slow recovery of the facial muscle movement. In group B, facial paralysis scores were improved from 4 to 2.6 during the 4 weeks; more rats showed a higher amplitude and shorter latency of CMAPs from day 14 to 28 after surgery; and increased axons and the expression of S100B and NF200 proteins and gradually decreased swelling in the injured facial nerve.Conclusion: ES promotes outgrowth and myelination of axons and a partial functional recovery of facial muscles in injured facial nerve rats. [ABSTRACT FROM AUTHOR]

Abstract—Insulating oil replacement is one of the most commonly used measures to solve oil deterioration in field transformers. However, the effects of oil replacement upon transformer condition assessment are still unknown. This article presents a simulated oil replacement in the process of an accelerated thermal aging test. The accelerated thermal aging experiment was conducted at 130°C for 80 days; insulating oil was replaced on the 25th day of aging. Several common condition assessment methods, including degree of polymerization of the paper, oil acidity, dielectric strength of the oil–paper insulation, moisture estimation, and furfural analysis, were compared before and after oil replacement. Results showed that oil replacement is effective in solving the degradation of insulating oil but not in restraining the aging of paper. The variation of dielectric strength of insulation paper caused by oil replacement could be neglected. Moisture estimation of insulation paper was closely related to the aging degree of oil–paper insulation but not obviously influenced by oil replacement. Furfural analysis would be seriously affected by oil replacement because furfural in oil was eliminated during the oil-drainage process, so the effect of oil replacement should be corrected when estimating transformer aging condition with furfural analysis method. [ABSTRACT FROM PUBLISHER]