Energy efficient cutting parameter optimization

Mechanical manufacturing industry consumes substantial energy with low energy efficiency. Increasing pressures from energy price and environmental directive force mechanical manufacturing industries to implement energy efficient technologies for reducing energy consumption and improving energy efficiency of their machining processes. In a practical machining process, cutting parameters are vital variables set by manufacturers in accordance with machining requirements of workpiece and machining condition. Proper selection of cutting parameters with energy consideration can effectively reduce energy consumption and improve energy efficiency of the machining process. Over the past 10 years, many researchers have been engaged in energy efficient cutting parameter optimization, and a large amount of literature have been published. This paper conducts a comprehensive literature review of current studies on energy efficient cutting parameter optimization to fully understand the recent advances in this research area. The energy consumption characteristics of machining process are analyzed by decomposing total energy consumption into electrical energy consumption of machine tool and embodied energy of cutting tool and cutting fluid. Current studies on energy efficient cutting parameter optimization by using experimental design method and energy models are reviewed in a comprehensive manner. Combined with the current status, future research directions of energy efficient cutting parameter optimization are presented

A framework for energy monitoring of machining workshops based on IoT

Machining workshop is a widely distributed manufacturing system that consumes massive energy in low efficiency. Due to the complicated and dynamic energy flow of the machining workshop, machinery manufacturers still lack an effective method to monitor and manage the energy efficiency. Hence, this paper proposes an energy efficiency monitoring system for machining workshop with the support of the newly emerging Internet of Things (IoT) technology. With the application of the proposed system, potential opportunities for energy efficiency improvement can be identified. Machinery manufacturers can easily reduce energy consumption and energy cost by managing the machining process

On the Generation of Medical Question-Answer Pairs

Question answering (QA) has achieved promising progress recently. However, answering a question in real-world scenarios like the medical domain is still challenging, due to the requirement of external knowledge and the insufficient quantity of high-quality training data. In the light of these challenges, we study the task of generating medical QA pairs in this paper. With the insight that each medical question can be considered as a sample from the latent distribution of questions given answers, we propose an automated medical QA pair generation framework, consisting of an unsupervised key phrase detector that explores unstructured material for validity, and a generator that involves a multi-pass decoder to integrate structural knowledge for diversity. A series of experiments have been conducted on a real-world dataset collected from the National Medical Licensing Examination of China. Both automatic evaluation and human annotation demonstrate the effectiveness of the proposed method. Further investigation shows that, by incorporating the generated QA pairs for training, significant improvement in terms of accuracy can be achieved for the examination QA system.Comment: AAAI 202

Managing product variety on online platform: Consumer heterogeneity and diseconomies of scope.

Recent innovations in e-commerce have led to the emergence of online retailing platforms, where millions of products are sold. Most of these products are sold by third-party sellers who pay a fee for the e-retailer (called the platform owner). We investigate how the e-retailer manages the various products in the presence of consumer heterogeneity and diseconomies of scope. Our analytical results indicate that the e-retailer prefers the platform-selling mode when consumers have stronger heterogeneity or when the value of a product is high; moreover, the consumer heterogeneity benefits the e-retailer and hurts the supplier. We also analyze the effect of the relationship of among categories on the e-retailer's choice. We show that the relationship among categories can invert the existing format. In addition, we find that the e-retailer may be better off and raise the number of products under strong diseconomies of scope when the categories are complements, and the opposite is true when the categories are substitutable

Salmonella Contamination in Layer Farms in China: Detection and Genetic Analysis

Salmonella is the most common cause of foodborne illnesses worldwide. Poultry eggs are a major contamination source of Salmonella. The prevalence of Salmonella has been effectively reduced since a series of measures were taken to reduce contamination in egg-laying houses. In the present study, 1,512 environmental samples obtained from layer farms of different production scales were screened in a voluntary Salmonella survey study. Contaminations were detected using a PCR method. Genetic relationships among Salmonella samples were specified using molecular typing by enterobacterial repetitive intergenic consensus (ERIC)-PCR. The survey results showed that two layer farms, located in the Shandong and Hebei provinces, were contaminated with Salmonella. Thirty-one samples from these two farms, including feed, drinking nipples, egg collection belt, air inlets and outlets, air, overshoes, and eggshells, were identified as Salmonella-positive. It was observed that certain samples within the henhouses as well as in the egg collecting areas showed relatively high genetic similarities. The survey conclusively revealed minor Salmonella contamination in northern China. Moreover, various areas within the layer farms were identified as part of the propagation chain of Salmonella. Furthermore, evidence of cross-contamination of Salmonella was found in the laying houses and egg collection areas, even between these two regions. Therefore, it is necessary to establish routine Salmonella detection and subsequent environmental control measures in order to decrease the prevalence of Salmonella

Integrated Optimization of Structure and Control Parameters for the Height Control System of a Vertical Spindle Cotton Picker

10.1186/s10033-021-00662-4Chinese Journal of Mechanical Engineering (English Edition)34113

Graphical analysis-based calculation method of concrete strength

This study established a three-dimensional random spherical aggregate model of concrete. Models with various volume contents of coarse aggregate were sliced, and slice areas were statistically analyzed. To study the effects of the coarse aggregate volume content and the interfacial transition zone (ITZ) strength on concrete’s compressive strength, a concrete strength calculation method based on graphical analysis was proposed. The ratio of crown area B to sectional area A of the spherical aggregate model was found to be close to 1.5. At the ITZ strength below 70% of the mortar strength, the increased volume content of coarse aggregate reduced the compressive strength of concrete, with the opposite trend observed at the ITZ strength exceeding 70% of the mortar strength

Design and Experiment of the Profiling Header of River Dike Mower

Drawing upon advancements in profiling technology, this paper presents an innovative lateral profiling mechanism for the header to improve mowing efficiency and the ability to adapt to terrain for river dike mowers. It delves into the imitation principle and forced situations. Furthermore, a novel lawn protection boot design has been introduced, capable of adjusting mowing heights with swift transitions. The structural integrity of this boot has been optimized through rigorous finite element analysis. Meanwhile, the rolling shaft and cutter have been carefully selected and designed, with a mechanical model of the cutter established to examine its motion and force characteristics. In addition, hydraulic circuits tailored to fulfill the required functions of the header have been devised, and key hydraulic components have been appropriately selected. Key components are subjected to finite element analysis by using ANSYS to verify and optimize their structural strength. Prototype testing and field trials are subsequently conducted, revealing that the mower can achieve a mowing speed of 0.85 m/s on flat ground and a 25-degree slope, thereby fulfilling the design requirements for mowing speed. The imitation mechanism adapts to different embankment terrains. Notably, the lawn protection boots offer adjustable mowing heights of 10.4 cm, 12 cm, and 14 cm, respectively, with a height adjustment range of approximately 2 cm for each position, meeting the requirement for adjusting mowing heights. In addition, the transition time between different positions of the lawn protection boots is less than 5 min, achieving rapid switching and operational efficiency. Furthermore, a mowing uniformity test is conducted by using a header equipped with profiling functionality. The results reveal that the mowing effect of the profiling header meets design requirements, demonstrating its effectiveness and reliability in agricultural applications