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To solve the problems existing in the process of teaching quality evaluation and to improve the accuracy of undergraduate teaching quality evaluation, a teaching quality evaluation model based on data mining algorithm is designed. Aiming at the factors such as the large amount of data to be mined and the quality of mining which is easily affected, the improved Apriori algorithm based on partition is applied in the model. Through the process of data collection and data preprocessing, the database suitable for association rule mining is established. Then we can find out which key factors can affect the teaching quality according to the analysis of association rules, so as to provide a strong basis for teaching decision-making and management. The results show that the data mining algorithm can describe the differences between the teaching quality grades of colleges, and acquire high-precision evaluation results of university teaching quality. Moreover, the error of teaching quality evaluation in colleges is far less than that of the current typical teaching quality evaluation methods.

This paper extends on previous research on the extraction and statistical analysis on relevant dynamic features (width, grayscale and radian combined with writing sequence information) in forensic handwriting examinations. In this paper, a larger signature database was gathered, including genuine signatures, freehand imitation signatures, random forgeries and tracing imitation signatures, which are often encountered in casework. After applying Principle Component Analysis (PCA) of the variables describing the proximity between specimens, a two-dimensional kernel density estimation was used to describe the variability of within-genuine comparisons and genuine–forgery comparisons. We show that the overlap between the within-genuine comparisons and the genuine–forgery comparisons depends on the imitated writer and on the forger as well. Then, in order to simulate casework conditions, cases were simulated by random sampling based on the collected signature dataset. Three-dimensional normal density estimation was used to estimate the numerator and denominator probability distribution used to compute a likelihood ratio (LR). The comparisons between the performance of the systems in SigComp2011 (based on static features) and the method presented in this paper (based on relevant dynamic features) showed that relevant dynamic features are better than static features in terms of accuracy, false acceptance rate, false rejection rate and calibration of likelihood ratios.

Copper slag is a common type of industrial waste with a low utilization rate, owing to the lack of effective treatment methods. Therefore, in this study to ensure maximum utilization, copper slag was modified at a high temperature, and then, used to prepare cement-based color facing mortar. The iron changed the color of the copper slag into purplish red; this slag was used as a colorant. The remaining elements, such as silicon and aluminum, functioned as cementitious materials. The results showed that the prepared color facing mortar had a bright crimson color. With 20% of modified slag, the color value of a* was 12.1, and l* was approximately 40 for the mortar, which means the sintered copper slag can effectively change the color of mortar. The compressive and flexural strengths with the same slag content sample are 6.83 MPa and 3.0 MPa, respectively; the water absorption rate was 2.4%, in accordance with the Chinese National Standard; and the cement-based materials can effectively prevent the leaching of heavy metals. The microstructure analysis showed that the most of the elements in copper slag can be utilized. We believe that the proposed method is effective for utilizing copper slags with high iron contents.

The information of the acute oral toxicity for most polycyclic aromatic hydrocarbons (PAHs) in mammals are lacking due to limited experimental resources, leading to a need to develop reliable in silico methods to evaluate the toxicity endpoint. In this study, we developed the quantitative structure-activity relationship (QSAR) models by genetic algorithm (GA) and multiple linear regression (MLR) for the rat acute oral toxicity (LD50) of PAHs following the strict validation principles of QSAR modeling recommended by OECD. The best QSAR model comprised eight simple 2D descriptors with definite physicochemical meaning, which showed that maximum atom-type electrotopological state, van der Waals surface area, mean atomic van der Waals volume, and total number of bonds are main influencing factors for the toxicity endpoint. A true external set (554 compounds) without rat acute oral toxicity values, and 22 limit test compounds, were firstly predicted along with reliability assessment. We also compared our proposed model with the OPERA predictions and recently published literature to prove the prediction reliability. Furthermore, the interspecies toxicity (iST) models of PAHs between rat and mouse were also established, validated and employed for filling data gap. Overall, our developed models should be applicable to new or untested or not yet synthesized PAHs falling within the applicability domain (AD) of the models for rapid acute oral toxicity prediction, thus being important for environmental or personal exposure risk assessment under regulatory frameworks.

Substation equipment has a large amount of heterogeneous information during its life cycle. However, when Autodesk Revit is used as the modeling software to build a BIM model of traction substation equipment, due to the limited type of model attribute parameters and parameter grouping methods, the model cannot meet the requirements. Requirements for information integration in the entire life cycle of equipment. Based on this, the thesis uses the MVC model of three-dimensional modeling platform and the technical support of synchronous calculation to propose a BIM-based substation equipment graphics calculation system. Taking the common cable trench, cover plate and foundation earthwork calculation in substation station engineering as an example, the realization method of main technology is explained.

At present, the existing technology has not yet realized the conversion process from the digital design model of the substation project to the construction model. This paper provides a solution to this problem. After the design model GIM is loaded into unity, the vertices and materials of the GIM model are read and loaded into the scene through the company's independent research and development of three-dimensional design software (STD-R). The model level information returned by the terminal corresponds to the loaded model one by one, thereby obtaining a model tree structure. The research results of the thesis provide convenience for the design and construction of power grid substation projects.

Sludge derived carbon (SBC) is a potential resource from sewage sludge disposal, and chemical pre-treatment is a necessary activation method for the improvement of the SBC quality. Two novel activators, i.e. Fenton and NaClO, were introduced to produce SBC precursors through the destruction of cell wall barriers and heterogeneous structures in sludge. High quality SBC-Fenton and SBC-NaClO were produced, with the BET having increased from 38 m2 g−1 in the control group to 253 m2 g−1 and 423 m2 g−1, respectively. The micro-porosity volume increased from 6% to 42% and 46% in the SBC-Fenton and SBC-NaClO, respectively, with the corresponding saturation adsorption capacity increasing from 33.1 mg g−1 to 71.5 mg g−1 and 67.8 mg g−1 based on Langmuir isotherms using methylene blue. The adsorption processes of the typical odorants H2S and NH3 were also tested using the SBC-Fenton and SBC-NaClO, which could reduce the landfill volume and odor emissions simultaneously, and around 2.1 mg g−1 and 0.68–2.24 mg g−1 of NH3 and H2S were adsorbed under different dosages. SBC could be a promising adsorption carrier and supporting substance for soil cover in landfills.

Under the energy Internet framework, the use of multiple energy complementary features such as electricity and gas can help alleviate the adverse effects of random fluctuations in renewable energy such as wind power. First of all, in order to make up for the bidding bias of wind power suppliers in the market in the past, a market trading framework considering various energy sources such as electricity and natural gas is given. Secondly, establish a game model of the market and natural gas market in which wind power suppliers participate in bidding. Among them, in the recent market, wind power merchants and traditional power producers participate in bidding by means of supply function bidding; in the natural gas market, natural gas merchants also use the supply function bidding method. Participate in the bidding and using Monte Carlo simulation to simulate the actual output of wind power. Finally, the rationality of the theoretical model is verified by a case study.

Energy operator who can supply electricity, heat and gas to users as an emerging operating entity will play an important role in the future energy market. How to develop energy operator pricing strategy and achieving operator and community users win-win situation has become an important issue. In this paper, the community energy internet, which includes PV, gas turbine and electric vehicle, aims to maximize the interests of both energy operator and users. Based on the Stackelberg game, this paper proposes an operator pricing, user load response, electric vehicle charging and discharging strategy, and the genetic algorithm is used to obtain the equilibrium solution. Finally, simulation results shows that the model can give full play to the potential of electric vehicle and controllable load, and verify the effectiveness of the model in coordinating the benefits of multi-stakeholder and improving the system load characteristics.

Aircraft flyover noise is a major source of community annoyance. The annoyance is affected by acoustic characteristics including onset rate, peak sound level and duration time. A simulated annoyance test was conducted on 30 subjects to analyze the effects from the three acoustic characteristics on annoyance. Results have shown that onset rate and duration time significantly determined annoyance while peak level had little effect. According to the importance of the exposure time, time above 75 dB was used as a new metric to illustrate the integral effects of onset rate and duration time. The curve of time above 75 dB was well fitted to an exponential-decrease equation which follows the sensory adaptation effect.