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For many optimization problems such as optimal techniques, compositions, producing process, the optimizing objectives in systems are complex relations with respect to a great deal of parameters. Generally, the objective function is hardly obtained, even the searching objective is unquantifiable. So it is difficult to model and optimize the complex systems to some extent.

To the above purpose, a novel approach is presented in this paper. It firstly utilizes the excellent fitting performance of neural network (NN) combined with expert knowledge (EK) to obtain the objective function, and secondly searches the optimal influential parameters with genetic algorithm (GA).

Peaks function inside Matlab and the acural application of comprehensive performance optimization in analog PID control system are studied, respectively. The results of simulation and the actual experiment both show that the modeling and optimizing method presented in the paper are effective.

Expert knowledge is needed for the fuzzy/unquantifiable objective.

The paper presents a useful way to model and optimize complex systems.

The combined approach based on NN, EK and GA is firstly presented and is effectively used in modeling and optimizing complex systems.

The spinel NiFe₂O₄ has been identified as being a potentially successful anti‐corrosion ceramic that can be used in aluminium electrolysis under molten salt corrosive conditions (970°C). The evaluation and fabrication processing of NiFe₂O₄ has been studied in this paper. According to the analysis and comparison of material properties, it has been concluded that fabrication technology for making anti‐corrosion electrode material would not be exceptionally difficult and therefore that the material has a strong potential for use in this service.

High-resolution remote sensing images possess a wealth of semantic information. However, these images often contain objects of different sizes and distributions, which make the semantic segmentation task challenging. In this paper, a bidirectional feature fusion network (BFFNet) is designed to address this challenge, which aims at increasing the accurate recognition of surface objects in order to effectively classify special features.

There are two main crucial elements in BFFNet. Firstly, the mean-weighted module (MWM) is used to obtain the key features in the main network. Secondly, the proposed polarization enhanced branch network performs feature extraction simultaneously with the main network to obtain different feature information. The authors then fuse these two features in both directions while applying a cross-entropy loss function to monitor the network training process. Finally, BFFNet is validated on two publicly available datasets, Potsdam and Vaihingen.

In this paper, a quantitative analysis method is used to illustrate that the proposed network achieves superior performance of 2–6%, respectively, compared to other mainstream segmentation networks from experimental results on two datasets. Complete ablation experiments are also conducted to demonstrate the effectiveness of the elements in the network. In summary, BFFNet has proven to be effective in achieving accurate identification of small objects and in reducing the effect of shadows on the segmentation process.

The originality of the paper is the proposal of a BFFNet based on multi-scale and multi-attention strategies to improve the ability to accurately segment high-resolution and complex remote sensing images, especially for small objects and shadow-obscured objects.

Marx suggested that it is infeasible and wrong to arrange the economic categories according to the order by which they have worked in history. Their order is determined by their interrelationship in the modern bourgeois society, which is in contrast to their natural sequence or that which is in accordance with the course of history. Sometimes, a logical sequence is precisely opposite to the historical sequence. There are many efforts to be done in the study of China’s economic and social issues with Marxist logical and historical methods. The paper aims to discuss these issues.

When reading Das Kapital, we can clearly see the historical materialism methods. Another method of Marxist political economics is the scientific abstract method.

This is based on the new development idea to carry out scientific and technological innovation and change the focus of development from quantity to quality. With regard to the supply side structural reform as the main focus, people’s ever-growing demand for a better life can be satisfied and the higher level dynamic supply–demand balance can be kept.

In fact, measures to remedy unbalanced and inadequate development of the social principal contradiction have been plainly indicated in the report delivered at the 19th National Congress of the Communist Party of China. This is based on the new development idea to carry out scientific and technological innovation and change the focus of development from quantity to quality.

The purpose of this paper is to properly calibrate the laser tracking system (LTS) prior to using it for metrology and improving the measuring accuracy of LTS.

A kinematics model that describes not only the motion but also geometric variations of LTS is developed. Effects of tracking mirror mechanism dimension errors on measured coordinates and target reflector alignment errors on sensor reading are investigated.

Through error analysis of the proposed model, it is claimed that gimbals axis misalignments and tracking mirror center offset are the key contributors to measure errors of LTS. Intensive simulation studies are conducted to check the validity of the theoretical results and various practical issues are also explored in the simulations. The simulation results demonstrate that under realistic conditions the 10‐parameter model is the minimal and complete model.

This model, together with its error model which is also presented in this paper, can be used for design, calibration, and control of LTS.

This paper develops a kinematics model that describes not only the motion but also geometric variations of LTS, and demonstrates that gimbals axis misalignments and tracking mirror center offset is the key contributor to measuring errors of LTS.

With the yearly increase of mileage and passenger volume in China's high-speed railway, the problems of traditional paper railway tickets have become increasingly prominent, including complexity of business handling process, low efficiency of ticket inspection and high cost of usage and management. This paper aims to make extensive references to successful experiences of electronic ticket applications both domestically and internationally. The research on key technologies and system implementation of railway electronic ticket with Chinese characteristics has been carried out.

Research in key technologies is conducted including synchronization technique in distributed heterogeneous database system, the grid-oriented passenger service record (PSR) data storage model, efficient access to massive PSR data under high concurrency condition, the linkage between face recognition service platforms and various terminals in large scenarios, and two-factor authentication of the e-ticket identification code based on the key and the user identity information. Focusing on the key technologies and architecture the of existing ticketing system, multiple service resources are expanded and developed such as electronic ticket clusters, PSR clusters, face recognition clusters and electronic ticket identification code clusters.

The proportion of paper ticket printed has dropped to 20%, saving more than 2 billion tickets annually since the launch of the application of E-ticketing nationwide. The average time for passengers to pass through the automatic ticket gates has decreased from 3 seconds to 1.3 seconds, significantly improving the efficiency of passenger transport organization. Meanwhile, problems of paper ticket counterfeiting, reselling and loss have been generally eliminated.

E-ticketing has laid a technical foundation for the further development of railway passenger transport services in the direction of digitalization and intelligence.

Revenue management (RM) is a significant technique to improve revenue with limited resources. With the macro environment of dramatically increasing transit capacity and rapid railway transport development in China, it is necessary to involve the theory of RM into the operation and decision of railway passenger transport.

This paper proposes the theory and framework of generalized RM of railway passenger transport (RMRPT), and the thoughts and methods of the main techniques in RMRPT, involving demand forecasting, line planning, inventory control, pricing strategies and information systems, are all studied and elaborated. The involved methods and techniques provide a sequential process to help with the decision-making for each stage of RMRPT. The corresponding techniques are integrated into the information system to support practical businesses in railway passenger transport.

The combination of the whole techniques devotes to railway benefit improvement and transit resource utilization and has been applied into the practical operation and organization of railway passenger transport.

The development of RMRPT would provide theoretical and technical support for the improvement of service quality as well as railway benefits and efficiency.

The purpose of this paper is to develop a suitable framework of sustainable urbanization performance evaluation from the view of efficiency for mitigating the unbalance between the theoretical research of sustainable urbanization and the practical need of sustainable urbanization.

A slack-restricted slack-based measure data envelopment analysis (DEA) model and two sustainable urbanization benchmarking methods with individual and centralized view, respectively, are developed based upon the classical DEA theory.

The empirical results show that China is now suffering a relatively low level of sustainable urbanization. Too much waste water emission, too small an urban population proportion, and too much resource wastage are the major factors that drive China’s urbanization away from sustainability.

Having the overall aim of practical urbanization, the proposed framework can help stakeholders recognize different sustainable urbanization performance levels by offering them accurate sustainable urbanization performance scores. The framework can also direct governments to improve the sustainable urbanization performance. The empirical analysis of China’s provincial region sustainable urbanization performance with the proposed framework further demonstrates the theoretical and practical value of this research.

Successive approximation register (SAR) analogue to digital converter (ADC) is well-known with regard to low-power operations. To make it energy-efficient and time-efficient, scientists are working for the last two decades, and it still needs the attention of the researchers. In actual work, there is no mechanism and circuitry for the production of two simultaneous comparator outputs in SAR ADC.

A small-sized, low-power and energy-efficient circuitry of a dual comparator and an amplifier is presented, which is the most important part of SAR ADC. The main idea is to design a multi-dimensional circuit which can deliver two quick parallel comparisons. The circuitry of the three devices is combined and miniaturized by introducing a lower number of MOSFET’s and small-sized capacitors in such a way that there is no need for any matching and calibration.

The supply voltage of the proposed comparator is 0.7 V with the overall power consumption of 0.257mW. The input and clock frequencies are 5 and 50 MHz, respectively. There is no requirement for any offset calibration and mismatching concerns due to sharing and centralization of spider-latch circuitry. The total offset voltages are 0.13 0.31 mV with 0.3VDD to VDD. All the components are small-sized and miniaturized to make the circuit cost-effective and energy-efficient. The rise and response time of comparator is around 100 ns. SNDR improved from 56 to 65 dB where the input-referred noise of an amplifier is 98mVrms.

The proposed design has no linear-complexity compared with the conventional comparator in both modes (working and standby); it is ultimately intended and designed for 11-bit SAR ADC. The circuit based on three rapid clock pulses for three different modes includes amplification and two parallel comparisons controlled and switched by a latch named as “spider-latch”.

This paper aims to study the oscillation phenomenon before chaos as well as its mechanism of occurrence in the energy-saving and emission-reduction system.

The system dynamics analysis, phase portrait analyses, equilibrium point analysis and bifurcation curve were applied to this paper.

First, the authors find an oscillation phenomenon previous to chaos. Second, on the one hand, the existence of two unstable saddles is the reason for the occurrence of oscillation phenomenon. On the other hand, the increasing of carbon emissions can arouse oscillation phenomenon.

This paper finds an oscillation phenomenon previous to chaos in the energy-saving and emission-reduction system. The mechanism of occurrence of oscillation phenomenon is studied. The existence of two unstable saddles is the reason for the occurrence of such oscillation phenomenon. The oscillation is related with fold bifurcation. The study also provides a theoretical basis for the further study of chaos control.