Evaluation System of Music Art Instructional Quality Based on Convolutional Neural Networks and Big Data Analysis.

In order to speed up the process of high-quality education and improve the level of education quality among the general public, people have pushed for the use of music art education in recent years. In this respect, this study covers the CNN-based assessment of the quality of music art teaching and creates a set of evaluation indices for that quality. The model architecture, network topology, learning parameters, and learning algorithm are all determined using this information, which also acts as the basis for the NN assessment model. The MATLAB simulation tool uses the CNN assessment model to train and learn a predetermined quantity of instructional quality data. The training experiment shows that this system can outperform other comparative systems in prediction accuracy by roughly 95%. Additionally, both the training and prediction accuracy of the model are completely acceptable. The evaluation findings and analytical data of the music art instructional quality assessment system created in this study can be used as a guide for determining the music art instructional quality and for making judgments regarding it.

1. Introduction

Music can be compared to a voice signal, but it is more complex and diverse. According to a set of rules, it is made up of various beats, harmonies, and melodies. Infecting and arousing people's emotions with the allure of beauty, art is a component of music aesthetics. The goal of moral education can be achieved by combining music education and moral education [1]. Giving students' individual aesthetic ability full play can enhance their body and mind health and support the development of their brains and bodies. Therefore, organising music art education at universities is very advantageous [2]. College teaching includes a significant amount of the evaluation of instructional quality. Currently, the issue of instructional quality is progressively catching people's attention. Recent years have seen a rise in the importance of the question of how to efficiently and impartially assess the instructional quality of college instructors. Instructional assessment has two definitions: macro and micro. It is a potent teaching feedback and adjustment tool. The term “generalised instructional assessment” refers to a thorough analysis of all the elements that influence how well instruction is carried out; however, the term “narrow sense of instructional assessment” is more specific. A guiding evaluation with benefits and drawbacks is presented to achieve the goal of teaching optimization, development, and improvement. Teachers' instructional impact is tested and judged through the corresponding teaching objectives and standards. Studying how to use CNN (Convolutional Neural Networks) [3-5] to assess the educational value of music art is therefore extremely important from both a theoretical and practical standpoint.

Evaluation of instructional quality can encourage teachers to modify their methods and fix issues in the teaching process in accordance with the evaluation's findings, thereby raising the standard of instruction across universities. Systematic quality evaluation of teaching is of utmost importance, and evaluation of instructional quality is a crucial link in ensuring and enhancing instructional quality. The simplest and most common way for determining the caliber of educational programmes is the weighted sum evaluation model. General experts predetermine a weight for each evaluation index, multiply the evaluation scores for each index by that weight, and then add the outcomes of the multiplication of each index to arrive at the final result. Due to the subjectivity of the experts, the results are not objective, and their credibility is poor. It might be difficult to evaluate the effectiveness of music art instruction, though. It is difficult for teachers and pupils to interact during instruction, and many other factors can affect how effective the instruction is. It is challenging to develop a logical, scientific framework for evaluating the educational value of music art that can assess that value impartially and objectively [6]. A “neural network” is a computer or information processing system that simulates the composition and operation of a biological brain. Pattern recognition, nonlinear classification, and artificial intelligence research have all benefited from the essential properties of NN as a novel technology, such as nonlinear mapping, learning classification, and real-time optimization. CNN belongs to the feedforward NN [7, 8].

In this paper, CNN is used to build a music art instructional quality assessment system to realize the evaluation of music art instructional quality in universities. Its innovations are as follows: (1) Combining music art teaching with CNN technology, this paper discusses the evaluation of music art instructional quality based on CNN and constructs a set of evaluation index system for music art instructional quality. On this basis, a music art instructional quality assessment system is constructed. (2) This paper improves and verifies the proposed model and provides a feasible solution for the instructional quality evaluation model. The experimental data show that it is completely feasible to use CNN to evaluate the instructional quality of music art, but also meet the precision requirements and indeed provide a convenient and practical tool for instructional quality evaluation.

2. Related Work

According to Biencinto et al., since it is difficult to compare the teaching of different disciplines, courses of different kinds, teaching links, and teaching objects, the consideration of the instructional quality assessment system is based primarily on the instructional quality that can visibly reflect the instructional quality and share characteristics. The most fundamental components are designed [9, 10]. Ma put forth an index system that is suitable for instructional assessment and proposed a data processing method that is standardised for index system data. On the basis of this, a BP network-based approach for assessing the quality of instruction is also recommended [11]. Weiss et al. [12] developed and implemented an AHP-based methodology for assessing the quality of instruction. Zhao and Chen can provide the teaching department with decision support by mining a range of relevant information based on the data currently present in university instructional assessments in order to better manage instruction and improve instruction quality [13]. Li designed a series of teacher instructional assessment systems using this evaluation model at its heart based on the simulation experiment of the BP network's instructional assessment model. The system primarily consists of functional modules including online evaluation of instructional quality, maintenance of evaluation findings, and thorough information search [14]. Bin introduced the existing problems and improvements of the BP algorithm and proposed the improvement methods of the BP algorithm and the simulated annealing method [15, 16]. Kim pointed out that quantitative evaluation can avoid the subjective and arbitrary defects of qualitative evaluation and can quickly process the collected data samples with the help of analysis tools. However, it lacks the comprehensive and meticulous characteristics of qualitative evaluation and cannot comprehensively collect the opinions and suggestions of evaluators on the instructional process. The evaluation results obtained are not flexible enough and have certain limitations.

However, at present, there are still some defects in the process of using NN to evaluate instructional quality. For example, the main body of evaluation is usually single, and the specific indicators of evaluation are rather general, which may cause the final result of evaluation to be distorted. Based on CNN, this paper discusses the evaluation of music art instructional quality and constructs a set of evaluation index system for music art instructional quality. It realizes the high efficiency, networking, and intelligence of music art instructional quality evaluation.

3. Methodology

3.1. CNN Technology Foundation

Music education can be classified into humanistic quality education. What it values is not how much knowledge and skills it teaches students, but more about how to train students' innovative ability, creative ability, and practical ability through the process of imparting knowledge and skills, which lies in the promotion and expansion of individual self. Therefore, it is extremely beneficial for universities to organize music art education. Instructional quality is the lifeline of universities, and instructional quality evaluation is an important measure to supervise and improve instructional quality. The instructional quality reflects the comprehensive strength of college teachers and influences the reputation of universities. Nowadays, the most effective way to define instructional quality is instructional assessment. The development of a perfect instructional quality monitoring system, the promotion of teaching work, and the ability for schools to shift their focus to improving quality are the main reasons why instructional quality evaluation is a key measure to improve the quality of education and teaching. These are frequently impossible to obtain through other methods. Traditional machine learning [17, 18] has traditionally trained models using manually extracted target features. It primarily used fundamental information in the field of music, such as loudness, frequency, and beat. It is challenging to manually design and extract acoustic abstract features like musical instruments, rhythm, and harmony because different musical genres are frequently very different from one another. Deep learning [19] uses a nonlinear relationship created by connecting several hidden layers to automatically capture the target's high-level abstract features. Among them, CNN is currently a popular network model. Figure 1 shows the basic neuron model.

Figure 1

Basic neuron model.

A network called NN is made up of several basic neurons. This technology's connections resemble the NN neurons found in human nerves, which are connected by a vast network of identical neurons. Each node, or neuron, is only in charge of a portion of the task [20]. Through the interconnection of neurons, NN may handle challenges that current artificial intelligence cannot address while simultaneously utilising its inherent nonlinear capacity to cope with relevant information. It is capable of doing additional intelligent functions, including speech recognition and intelligent control. It not only encourages the use of artificial intelligence in a variety of contexts, but also combines with the conventional method, considerably enhancing the breadth and depth of artificial NN applications. The neuron model, the fundamental building block of NN, consists of three components as follows: (1) The connection strength is represented by the weights on each connection, with positive weights denoting excitation and negative weights denoting inhibition. The group of connection weights corresponds to the synapses of biological neurons. (2) A summation unit, which computes the linear and weighted combination of each input piece of data. (3) A nonlinear excitation function, which limits the output amplitude of neurons in a specific range and functions as a nonlinear mapping function. The complexity of the network structure will have a significant impact on NN's capacity for generalisation. The size of the network structure, the number of hidden layers, and the number of hidden nodes will all have an impact on how well the network performs, and the network model's ability to generalise will improve as the network structure is simplified. As a result, in actual practice, the network structure can be improved by lowering the dimension of the input data (i.e., by lowering the quantity of neurons in the input layer of the NN and the quantity of nodes in the hidden layer). The model of the CNN structure is shown in Figure 2.

Figure 2

CNN structure model.

The original evaluation data must perform some preliminary data processing to interfere with the evaluation because the evaluators' influence on the instructional assessment result data is significant. Otherwise, it will affect CNN's prediction results as well as the algorithm's learning speed and calculation accuracy. In order to calculate the gradient, network weights and thresholds are added from each training sample. There are two ways to deal with gradient descent algorithm: (1) Incremental Mode. Gradient calculation and weight modification are performed before each input enters the network. (2) Batch Mode. In batch mode, after all network training parameters are applied to the network, their weights and thresholds can be modified. The connection mode between neurons in CNN convolution layer is completely different from that of traditional full connection layer. In order to get more abstract features, convolution layer tries to analyze each small block in NN more deeply. CNN has the characteristics of sharing weights, local sensing domain, and downsampling. Sharing weights greatly reduces the parameters of the network, the data processing method in local perception domain can simplify the network structure, and the downsampling method can effectively extract features from the data. When the input is a multidimensional image, these features make CNN's superiority more obvious. Before the NN evaluation model is used, the collected original teacher's teaching-related data need to be preprocessed, so the original data need to be normalized first. NN's study can also be conducted online.

3.2. Design and Implementation of Music Instructional Quality Assessment System

In accordance with its functional requirements, the system shall do the following five essential tasks: system administration, instructional assessment, basic data management, instructor evaluation results management, evaluation model research, and evaluation. The evaluation index system's hierarchy is robust. All first-level evaluation indexes are set in accordance with the final evaluation results in accordance with the analytical hierarchy process based on the principle of system hierarchy, while all second-level evaluation indexes that are related to the same first-level evaluation indexes are set in accordance with the first-level evaluation indexes. On the other hand, AHP can be used to screen the secondary evaluation indexes according to their weights so as to reduce the input of CNN and achieve the goal of optimizing the network structure. In the design process, in order to make the results more objective and accurate and avoid the influence of many human factors, the whole instructional assessment system is roughly divided into three parts as follows: (1) Evaluation management system for teachers' job evaluation—its main function is to evaluate the teaching of the corresponding teachers in students' spare time. (2) Evaluation among experienced teachers. (3) Experts of the supervision team evaluate a teacher's classroom teaching. The final evaluation results will consist of these three parts. The evaluation indexes of art instructional quality are shown in Table 1.

Table 1

Evaluation index of music art instructional quality.

	Primary index	Secondary index
Evaluation index system of music art instructional quality	Instructional attitude	Rigorous lesson preparation and complete lesson plan
		Tutor students patiently
	Instructional ability	Systematization of teaching content
		Integrating theory with practice
		Auxiliary teaching means
		Treatment of key and difficult points
		Language organization, clean writing on the blackboard
		Mobilize students' enthusiasm
	Content of courses	Choose and handle the content properly
		Highlighted content
	Instructional method	Teaching students in accordance with their aptitude and flexible methods
		Pay attention to inspiration and ability
		Pay attention to communication and interaction with students
	Instructional effect	Students have a comprehensive grasp of knowledge points
		Improving students' aesthetic ability

When the model is well trained, according to this model, input the preprocessed students' evaluation data on teachers, and you can get the final result calculated by the model. In order to avoid “saturation phenomenon,” the input samples of NN are normalized in this paper. NN is a function, and the input should be normalized to [0, 1]. The normalization formula adopted in this paper is as follows:

In the formula, X represents the normalized NN input value; I represents the unprocessed NN input value; Imax represents the maximum value of the NN input; and Imin represents the minimum value of the NN input.

Firstly, this paper constructs the hierarchical relationship of relevant elements. Secondly, construct a judgment matrix for the determined hierarchy, and then check the consistency of the judgment matrix. Finally, the weight values of evaluation index elements at all levels are calculated. In this paper, through consultation, interviews, questionnaires, and other forms, on this basis, through sorting out the initial data and qualitative and quantitative analysis, the proportion of evaluation indicators in the whole index system is initially formed. It is necessary to introduce nonlinear activation function into CNN.

A typical tangent or logarithmic S curve or another form of S-shaped curve is used to represent a monotone differentiable function with continuous values in (0, 1) or (−1, 1), that is, a typical S-shaped transfer function:

S-shaped function is smooth, asymptotic, and monotonic.

There are numerous parameters involved in NN training, and determining these parameters will determine the network's structure. There are some guiding principles involved in determining these parameters. The accuracy will increase and the error between the actual value and the expected value will decrease as the number of hidden layers increases; however, the network structure will become larger and the training process will take longer. As a result, the three-layer network structure used in this paper has just one hidden layer. The following mathematical formulas are used in the training of NN:

Among them, x is the input component and is the ith neuron component before preprocessing; xmin and xmax are the minimum and maximum values, respectively, and are the minimum and maximum values of all input components of the ith neuron.

In this paper, the gradient descent method is used to solve the approximation problem of NN. First, take X=[x1, x2, x3,…, x] as the input vector of the training network, and take H=[y1, y2, y3,…, y] as the radial vector of the training network; then, the Gaussian function formula is

Among them, C is the center vector of the jth node of the neural training network; B=[b1, b2, b3,…, b] is the base width vector; b is the base width parameter of the node j, and b > 0. W=[w1, w2, w3,…, w] is the weight vector of the network. In addition, in a certain range, the optimal number of hidden nodes is determined by comprehensively comparing the network performance indexes of different numbers of neurons.

If the expected output vector of neurons in the output layer is

the actual output vector is

The correction error of each neuron in the output layer is

According to the calculated correction error d, whs and yh of each neuron in the output layer, the correction error of each neuron in the hidden layer can be calculated as follows:

According to the back propagation of the correction error, the connection weights and thresholds are corrected layer by layer. The adjustment amount of the threshold is

In the formula, η is the learning step size, and η ∈ [0.01, 0.1].

This paper quantifies the qualitative evaluation of instructional quality given by evaluators in the evaluation process, that is, quantifies the qualitative evaluation, and the quantified evaluation scores can be used as a part to participate in the final evaluation of instructional quality. Instructional evaluation activities can be divided into the collection and initialization of teaching raw data, the construction of assessment system, the implementation of instructional assessment, the processing and output of evaluation results, and the inquiry of evaluation information. Among them, the acquisition and initialization of teaching raw data includes two generalisation operations: data input and batch import, and information query has the extension operation of data export. In addition, the system should basically unify the user interface, with beautiful design interface, concise function and operation, rich and detailed help, and powerful flexible customization function. Users can customize system function modules and operating habits and display style templates according to their different needs and operating habits.

4. Result Analysis and Discussion

The entire system is studied and designed in a coherent manner in the chapter on system design. The system's development objective is established following a thorough demand study of the entire system. This essay introduces the development of the evaluation model in detail and concentrates on the design of the CNN-based assessment system of music art instructional quality. The evaluation model is tested by experiments in this chapter. In this chapter, the viability of the NN model for evaluating instructional quality is simulated using MATLAB tools. It is among the best programmes for designing and analysing NN systems. The improvement of the impact of school education is the primary responsibility of the music instructional quality evaluation system. Through this approach, students can provide feedback to teachers on their classroom instruction, and teachers can then make the necessary changes in response to the feedback in order to address any shortcomings in the teaching activities and raise the standard of instruction. The three main steps of the NN-based music art instructional quality assessment system are as follows: (1) Before successfully constructing the NN and training the network, it is required to prepare the data so that it complies with the index's requirements and use the qualifying data as the network's input training samples. (2) Assess the first step's training network to determine the true impact of network training. (3) Determine the network's training impact before developing a true and practical NN evaluation model. According to the evaluation index of instructional quality, a classroom teaching questionnaire is made, and students can choose and grade the indexes of teachers. In this paper, the six highest scores are removed, and the six lowest scores are taken as the average so that some students' irresponsible evaluation of teachers can be eliminated. On the basis of the above principles, collect and process samples. Standardize the collected sample data. These data are converted into data between [0, 1] so that the preprocessed data can meet the requirements of NN training samples, which is convenient for NN processing. At the same time, AHP is used to screen indicators. Keep the index whose total ranking weight of hierarchy is greater than the threshold.

The programme is put into action in CNN MATLAB, and network testing and training are done. One portion of the preprocessed data is designated as training data, and the other portion is designated as test data. The format calls for first entering the training samples into two instructional assessment models for learning, and then entering the test samples into two evaluation models for testing. Figure 3 displays the various networks' training errors. In Figure 4, the experimental error is displayed.

Figure 3

Schematic diagram of network training error.

Figure 4

Schematic diagram of experimental test error.

In this paper, the comprehensive evaluation value of the classroom by the experts of the teaching supervision group is adopted, and the sample data is used to train the network. The results of systematic calculation are sorted and compared with the sorting results of comprehensive evaluation of real instructional quality, and the evaluation effect of music and art instructional quality is analyzed. The ranking result of the comprehensive evaluation of the real instructional quality is the synthesis of the quantitative evaluation results of teachers, the evaluation of teachers' teaching observation and evaluation, the promotion evaluation of teachers' professional titles, and the qualitative evaluation of the supervision team in the past five years. Through the manual ranking of teaching experts, a more accurate and comprehensive ranking result recognized by the whole department is obtained. Figure 5 shows the comparison of F-values of different models. Figure 6 shows the comparison of prediction accuracy of different models.

Figure 5

Comparison of F-values of different models.

Figure 6

Comparison of prediction accuracy of different models.

In this paper, 50 sets of data are used to test several commonly used evaluation models. The experimental results are shown in Table 2.

Table 2

Prediction results of different models.

Sample	Multivariate linearity		Partial least squares		CNN
	Predicted value	Relative error	Predicted value	Relative error	Predicted value	Relative error
21	7.1941	7.21	7.5608	8.45	6.0416	0.36
22	7.3632	4.89	6.9721	3.74	6.1417	2.51
23	7.9603	6.53	8.3257	1.99	8.3916	1.28
24	8.9924	4.39	8.6214	6.92	9.7410	3.06
25	8.9042	5.47	8.7456	4.97	7.0612	0.39

Table 2 shows that, among all evaluation models of the quality of music art instruction, the CNN model suggested in this paper has the advantages of high evaluation accuracy and small relative error. The test tool used is LoadRunner after the network and test environment have been created. This instrument is primarily used to gauge the system's resistance to pressure. It can also accurately test the system's data flow, count the amount of time the system takes to respond, and run statistical analyses on various access data for various media objects. In addition to separately testing the function and performance, multipoint distributed testing is also necessary. It also features a typical SMS interface. Figure 7 displays the operational effectiveness of various systems.

Figure 7

Comparison of operating efficiency of different systems.

Comparing this system to the other two, it is clear that it operates more efficiently. The evaluation results following network training, and expert evaluation results are shown in Table 3. A comparison of the test results from the test set and the actual evaluation outcomes is shown in Table 4.

Table 3

Evaluation results after network training and expert evaluation results.

Serial number	Expert evaluation	Network evaluation in this paper
1	0.754	0.761
2	0.846	0.849
3	0.902	0.903
4	0.857	0.851
5	0.869	0.862
6	0.915	0.918
7	0.841	0.840
8	0.829	0.828
9	0.932	0.930
10	0.907	0.909

Table 4

Comparison between test results of test set and actual evaluation results.

Serial number	Expert evaluation	Network evaluation in this paper
11	0.832	0.833
12	0.859	0.861
13	0.917	0.915
14	0.882	0.880
15	0.897	0.899

Compared to other comparison systems, the training experiment demonstrates that this system's prediction accuracy can reach about 95%. The superiority of NN is fully acknowledged by the evaluation model for CNN's music art education quality assessment. The music art instructional quality assessment system developed in this paper can efficiently assess the music art instructional quality, and its evaluation results and analysis data can serve as a guide for assessing and making decisions regarding the music art instructional quality.

5. Conclusions

A thorough plan must be created and devoted to the optimization of music art education and teaching in order for students to excel in a particular area of music education in order to effectively improve the quality of music art education in universities. The assessment of the effectiveness of music instruction can offer some theoretical and practical support for raising the standard of music education. The construction and training of network models are thoroughly studied in this paper, which also provides an introduction to NN knowledge. The system for evaluating the quality of music and art instruction developed in this paper carries out the tasks of gathering evaluation data and managing evaluation results in the background, both of which will significantly increase the efficiency and effectiveness of the evaluation. A specific amount of instructional quality data is trained and learned using the CNN evaluation model in the MATLAB simulation tool. The training experiment demonstrates that this system can make predictions with an accuracy of about 95%, which is higher than other comparison systems. Additionally, the model's training and prediction accuracy fall entirely within the acceptable range. The quality of music and visual arts education is evaluated using a new method developed by CNN that fully exploits the benefits of NN. The authors think that in the future research of instructional assessment algorithms, there will be newer and more developed schemes applied to practise. It can objectively and fairly evaluate the instructional quality of music art, inspire teachers, improve the instructional quality, and cultivate exceptional talents. The following areas will be the focus of additional study: refining the NN assessment system of instructional quality and further developing and designing other subsystems of NN evaluation of instructional quality.