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This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and verifies its decoupling effect..

The machine–hydraulic cross-linking coupling is studied as the coupling behavior of the hydraulically driven quadruped robot, and the mechanical dynamics coupling force of the robot system is controlled as the disturbance force of the hydraulic system through the Jacobian matrix transformation. According to the principle of multivariable decoupling, a prediction-based neural network model reference decoupling control method is proposed; each module of the control algorithm is designed one by one, and the stability of the system is analyzed by the Lyapunov stability theorem.

The simulation and experimental research on the robot joint decoupling control method is carried out, and the prediction-based neural network model reference decoupling control method is compared with the decoupling control method without any decoupling control method. The results show that taking the coupling effect experiment between the hip joint and knee joint as an example, after using the predictive neural network model reference decoupling control method, the phase lag of the hip joint response line was reduced from 20.3° to 14.8°, the amplitude attenuation was reduced from 1.82% to 0.21%, the maximum error of the knee joint coupling line was reduced from 0.67 mm to 0.16 mm and the coupling effect between the hip joint and knee joint was reduced from 1.9% to 0.48%, achieving good decoupling.

The prediction-based neural network model reference decoupling control method proposed in this paper can use the neural network model to predict the next output of the system according to the input and output. Finally, the weights of the neural network are corrected online according to the predicted output and the given reference output, so that the optimization index of the neural network decoupling controller is extremely small, and the purpose of decoupling control is achieved.

The paper attempts to discuss the impact of reference price effect on pricing decisions.

With the growth of the Internet and e-commerce, more and more customers purchase products in through online channels and choose products by comparing different prices and services, and the reference price effect has an impact on pricing decisions. To investigate the impact of consumers' reference price effect on the dual-channel supply chain, the authors establish a basic model consisting of a single dominant manufacturer and a single downstream retailer, and analyze the optional decisions under different situations and discuss the influence of reference price effect. Finally, a number case verifies the validity and rationality of the proposed model.

The results show that (1) the reference price effect has varying effects on the price, channel demand and income of manufacturers and retailers in the channel depending on the role of customers' channel preferences. (2) The manufacturer's online channel demand and profits always increase with the reference pricing effect, whereas the retailer's offline demand and profits always decline. (3) When the proportion of consumers preferring offline is higher, the manufacturer's network price and wholesale price increase with the reference price effect, while the retailer's retail price decreases with the reference price effect; when the proportion of consumers preferring offline is lower, the opposite is true, and the centralized decision results are consistent with the decentralized decision results.

This paper can clarify the impact of consumer reference price effects on the operation of dual-channel supply chains, and help inform pricing decisions of manufacturers and retailers in dual-channel supply chains.

The proposed approach can well analyze the impact of consumer reference price effect and give channel their optional decisions.

Motivation of the employees is extensively considered as an antidote for the overall success of the organizations. This study primarily aims to investigate the impact of motivation on the job performance of university librarians in Pakistan.

Quantitative research design followed by a survey method under an extended theory of motivation was applied. Data were collected from 123 professional librarians of 79 university libraries in Punjab province, Pakistan. The study tested hypotheses having used regression statistical test through Statistical Package for Social Sciences Software (Version 26).

Results of the study revealed that motivation (intrinsic and extrinsic), the expectation of benefits, satisfaction of meta needs and challenging situations have a strong positive impact on the optimum job performance of university librarians.

This research has theoretical implications for the researchers and practical insights for human resource managers to get maximum outcomes for organizational development. The results of the study may be generalized to the university libraries of other countries having similar socio-economic and cultural situations.

This study developed a framework based upon empirically tested hypotheses that might be used as drivers for different motivation practices to augment employees’ commitment to the organizations.

This study aims to determine if automated coding with regular expression is a strong methodology to identify themes in virtual reference chat.

The authors used a combination of manual and automated coding of chat transcripts for a period of two years to identify the categories of questions related to the new library system. This methodology enabled them to determine if regular expression accurately identified the topics of chat transcripts.

They discovered that regular expression is an appropriate method to identify themes in virtual reference interactions. This method enabled them to establish that patrons asked questions related to system changes in the weeks following their implementations.

This study highlights a new methodology for transcript analysis.

This research aims to explore the integration of Bing Chat, an artificial intelligence (AI)-powered conversational assistant, into academic libraries and its potential impact on reference services.

This study analyzes existing literature to investigate the integration of Bing Chat in academic libraries. This research focuses on its features, capabilities and implications for enhancing user experiences and addressing information needs.

The findings highlight that Bing Chat’s conversational interface facilitates more dynamic and context-aware reference interactions, fostering user empowerment and personalized learning pathways. The integration of Bing Chat with existing library resources enhances resource discovery, navigational assistance and engagement with visual content. However, challenges related to accuracy, privacy and algorithmic bias require careful consideration.

This research contributes to the literature by providing an in-depth exploration of Bing Chat’s integration into academic libraries, emphasizing its transformative potential for reference services. This study addresses ethical and social dimensions associated with AI-driven tools in library environments, offering insights into ensuring fairness, privacy and user trust.

Component positioning is an important part of aircraft assembly, aiming at the problem that it is difficult to accurately fall into the corresponding ball socket for the ball head connected with aircraft component. This study aims to propose a ball head adaptive positioning method based on impedance control.

First, a target impedance model for ball head positioning is constructed, and a reference positioning trajectory is generated online based on the contact force between the ball head and the ball socket. Second, the target impedance parameters were optimized based on the artificial fish swarm algorithm. Third, to improve the robustness of the impedance controller in unknown environments, a controller is designed based on model reference adaptive control (MRAC) theory and an adaptive impedance control model is built in the Simulink environment. Finally, a series of ball head positioning experiments are carried out.

During the positioning of the ball head, the contact force between the ball head and the ball socket is maintained at a low level. After the positioning, the horizontal contact force between the ball head and the socket is less than 2 N. When the position of the contact environment has the same change during ball head positioning, the contact force between the ball head and the ball socket under standard impedance control will increase to 44 N, while the contact force of the ball head and the ball socket under adaptive impedance control will only increase to 19 N.

In this paper, impedance control is used to decouple the force-position relationship of the ball head during positioning, which makes the entire process of ball head positioning complete under low stress conditions. At the same time, by constructing an adaptive impedance controller based on MRAC, the robustness of the positioning system under changes in the contact environment position is greatly improved.

This paper investigates thermal mass performance (TMP) in hot climates. The impact of using precast concrete (PC) as a core envelope with different insulation materials has been studied. The aim is to find the effect of building mass with different weights on indoor energy consumption, specifically cooling load in hot climates.

This research adopted a case study and simulation methods to find out the efficiency of different mass performances in hot and humid climate conditions. Different scenarios of light, moderate and heavyweight mass using PC have been developed and simulated. The impact of these scenarios on indoor cooling load has been investigated using the integrated environment solution-virtual environment (IES-VE) software.

The results showed that adopting a moderate weight mass of two PC sheets and a cavity layer in between can reduce indoor air temperature by 1.17 °C; however, this type of mass may increase the cooling demand. On the other hand, it has been proven that adopting a heavyweight mass for building envelopes and increasing the insulation material has a significant impact on reducing the cooling load. Using a PC Sandwich panel and increasing the insulation material layers for external walls and thickness by 50 mm will reduce the cooling load by 15.8%. Therefore, the heavyweight mass is more efficient compared to lightweight and moderate mass in hot, humid climate areas such as the UAE, in spite of the positive indoor TMP that can be provided by the lightweight mass in reducing the indoor air temperature in the summer season.

This research contributes to the thermal mass concept as one of these strategies that have recently been adopted to optimize the thermal performance of buildings and developments. Efficient TMP can have a massive impact on reducing energy consumption. However, less work has investigated TMP in hot and humid climate conditions. Furthermore, the impact of the PC on indoor thermal performance within hot climate areas has not been studied yet. The findings of this study on TMP in the summer season can be generated in all hot climate zones, and investigating the TMP in other seasons can be extended in future studies.

Predicting highly cited papers can enable an evaluation of the potential of papers and the early detection and determination of academic achievement value. However, most highly cited paper prediction studies consider early citation information, so predicting highly cited papers by publication is challenging. Therefore, the authors propose a method for predicting early highly cited papers based on their own features.

This research analyzed academic papers published in the Journal of the Association for Computing Machinery (ACM) from 2000 to 2013. Five types of features were extracted: paper features, journal features, author features, reference features and semantic features. Subsequently, the authors applied a deep neural network (DNN), support vector machine (SVM), decision tree (DT) and logistic regression (LGR), and they predicted highly cited papers 1–3 years after publication.

Experimental results showed that early highly cited academic papers are predictable when they are first published. The authors’ prediction models showed considerable performance. This study further confirmed that the features of references and authors play an important role in predicting early highly cited papers. In addition, the proportion of high-quality journal references has a more significant impact on prediction.

Based on the available information at the time of publication, this study proposed an effective early highly cited paper prediction model. This study facilitates the early discovery and realization of the value of scientific and technological achievements.

This paper aims to describe a proposal for an innovative method of normal shock wave–turbulent boundary layer interaction (SBLI) and shock-induced separation control.

The concept is based on the introduction of a tangentially moving wall upstream of the shock wave and in the interaction region. The SBLI control mechanism may be implemented as a closed belt floating on an air cushion, sliding over two cylinders and forming the outer skin of the suction side of the airfoil. The presented exploratory numerical study is conducted with SPARC solver (steady 2D RANS). The effect of the moving wall is presented for the NACA 0012 airfoil operating in transonic conditions.

To assess the accuracy of obtained solutions, validation of the computational model is demonstrated against the experimental data of Harris, Ladson & Hill and Mineck & Hartwich (NASA Langley). The comparison is conducted not only for the reference (impermeable) but also for the perforated (permeable) surface NACA 0012 airfoils. Subsequent numerical analysis of SBLI control by moving wall confirms that for the selected velocity ratios, the method is able to improve the shock-upstream boundary layer and counteract flow separation, significantly increasing the airfoil aerodynamic performance.

The moving wall concept as a means of normal shock wave–turbulent boundary layer interaction and shock-induced separation control has been investigated in detail for the first time. The study quantified the necessary operational requirements of such a system and practicable aerodynamic efficiency gains and simultaneously revealed the considerable potential of this promising idea, stimulating a new direction for future investigations regarding SBLI control.

This study aims to investigate how Citation Gecko technology might help libraries provide better research support services. The paper explains specifically how Citation Gecko can help libraries provide more precise and thorough references, save time and enable methodical literature reviews and scoping studies amid the constantly evolving nature of research domains. The paper also considers how businesses and libraries can gain from implementing the technology.

The paper’s conceptual study of the function of librarians in assisting researchers – particularly in the setting of exhaustive literature reviews and scoping studies – forms the foundation of the piece. The authors talk about the difficulties in guaranteeing the authenticity and comprehensiveness of the literature review process and the significance of adopting tools like Citation Gecko to help with this process. The possible adoption of Citation Gecko in libraries is also forecasted using the technological adoption model paradigm.

Libraries that use Citation Gecko technology provide better research support services by providing accurate and comprehensive references, saving time and assisting systematic literature surveys and scoping studies. The tool is simple to use and does not require professional training due to its user-friendly interface and ability to produce references fast. Using Citation Gecko technology can enhance libraries’ capacities to support researchers, faculty and students in their research projects by making a significant contribution to systematic surveys and referencing efforts.

This study adds to the continuing discussion about how libraries may use technology to improve the services they provide to users who need research support. It had never been looked into how citation Gecko might help libraries with their reference and systematic review study offerings.