Research on module configuration design by case-based reasoning oriented on CNC machine tool

CNC alatni stroj je simbol razvijene proizvodne tehnologije. Uvođenje modularnog projekta u postupke projektiranja CNC alatnih strojeva ima važnu teoretsku i praktičnu vrijednost. Ovaj rad promiče metodu projektiranja konfiguracije modula kombiniranjem modularnog projektiranja i promišljanja zasnovanog na slučaju (case-based reasoning-CBR). Riješeni su ključni tehnološki postupci uključujući transformaciju zahtjeva kupca, pronalaženje sličnog slučaja i procjenu slučaja. U radu su analizirani primanje i transformacija zahtjeva kupaca i mapiranje prema procjenama važnosti zahtjeva kupaca do procjena važnosti tehničkih karakteristika proizvoda. Proučavane su tehnologije CBR-a i primijenjen je fuzzy omjer prioriteta sličnosti i algoritam Grey analize korelacije kako bi se odredio i procijenio slučaj koji ima prioritet te izabrao slučaj proizvoda koji konačno najbolje odgovara zahtjevima kupca. Izabrana je CNC horizontalna tokarilica kao primjer učinkovitosti algoritma.CNC machine tool is a symbol of advanced manufacturing technology. The introduction of modular design into the design processes of CNC machine tool has important theoretical and practical value. Combining modular design with case-based reasoning (CBR), this paper puts forward one method of module configuration design. The key technologies including the transformation of customer requirements, the case retrieval and the case evaluation have been solved. This paper analysed the acquisition and transformation of customer requirements, and the mappings from the importance ratings of customer requirements to the importance ratings of product technical characteristics. The paper studied the technologies of CBR, and used the fuzzy similarity priority ratio and grey correlation analysis algorithm to realize the calculation of case priority and the case evaluation, and picked out the product case that best matches the customer requirements finally. CNC horizontal lathe is selected as an example to show the algorithm effectiveness

Evaluation of microstructure variation of TC11 alloy after electroshocking treatment

Electro-shocking treatment (EST) has been investigated as a pathway to optimise the microstructure and mechanical properties of titanium alloys. The thermal conditions introduced by EST resulted in a phase transformation from α to β. The fraction of β phase decreased from 25.27% to 19.47% after EST for 0.02 s, which was possibly caused by the recrystallization of α phase. The application of EST for 0.04 s resulted in an increase in volume fraction of the β phase to 26.95%. The energy introduced by EST resulted in changes to the direction and intensity of texture within the microstructure with the texture intensity of the α phase increasing from 4.94 to 8.52, and that of β both increased from 3.35 to 9.88 after 0.04 s EST. © 2020 The Authors

Fermi resonance-algebraic model for molecular vibrational spectra

A Fermi resonance-algebraic model is proposed for molecular vibrations, where a U(2) algebra is used for describing the vibrations of each bond, and Fermi resonances between stretching and bending modes are taken into account. The model for a bent molecule XY_2 and a molecule XY_3 is successfully applied to fit the recently observed vibrational spectrum of the water molecule and arsine (AsH_3), respectively, and results are compared with those of other models. Calculations show that algebraic approaches can be used as an effective method for describing molecular vibrations with small standard deviations

Carbon footprint and driving forces of saline agriculture in coastally reclaimed areas of eastern China: a survey of four staple crops

Carbon emissions have always been a key issue in agricultural production. Because of the specific natural factors in the soil of saline agriculture, there are distinctive characteristics in saline agricultural production as compared with traditional agricultural zones. Here, we have adopted the theory of life cycle assessment, and employed the Intergovernmental Panel on Climate Change (IPCC) greenhouse gas (GHG) field calculation to estimate the GHG emissions, derived from the staple crop productions (i.e., barley, wheat, corn and rice). In addition, our study further analyzed the main driving forces of carbon emissions, and proposed some effective measures to reduce them. Our results have showed that: (1) Carbon footprint from the four crops in the study area varies from 0.63 to 0.77 kg CO2 eq•kg-1, which is higher than that from traditional agriculture; (2) GHG emissions from Fertilizer-Nitrogen (N) manufacture and inorganic N application have contributed to the greatest percentage of carbon footprint. Compared with traditional agricultural zones, fertilizer-N application and paddy irrigation involved with crop productions have overall greater contributions to carbon footprint; (3) Carbon emissions from saline agriculture can be reduced significantly by planting-breeding combination to reduce the amount of N fertilizer application, improving the traditional rotation system, and developing water-saving agriculture and ecological agriculture

A Conscious Resting State fMRI Study in SLE Patients Without Major Neuropsychiatric Manifestations

Neuropsychiatric systemic lupus erythematosus (NPSLE) is one of the main causes of death in patients with systemic lupus erythematosus (SLE). Signs and symptoms of NPSLE are heterogeneous, and it is hard to diagnose, and treat NPSLE patients in the early stage. We conducted this study to explore the possible brain activity changes using resting state functional magnetic resonance imaging (rs-fMRI) in SLE patients without major neuropsychiatric manifestations (non-NPSLE patients). We also tried to investigate the possible associations among brain activity, disease activity, depression, and anxiety. In our study, 118 non-NPSLE patients and 81 healthy controls (HC) were recruited. Rs-fMRI data were used to calculate the regional homogeneity (ReHo) in all participants. We found decreased ReHo values in the fusiform gyrus and thalamus and increased ReHo values in the parahippocampal gyrus and uncus. The disease activity was positively correlated with ReHo values of the cerebellum and negatively correlated with values in the frontal gyrus. Several brain areas showed correlations with depressive and anxiety statuses. These results suggested that abnormal brain activities might occur before NPSLE and might be the foundation of anxiety and depression symptoms. Early detection and proper treatment of brain dysfunction might prevent the progression to NPSLE. More studies are needed to understand the complicated underlying mechanisms

High-Quality Development Evaluation and Spatial Evolution Analysis of Urban Agglomerations in the Middle Reaches of the Yangtze River

Urban agglomeration in the middle reaches of the Yangtze River is key to the rise of central China, and an important engine for the high-quality development of the Yangtze River economic belt. Research on urban agglomeration in the middle reaches of the Yangtze River focuses mainly on economic development, ecological environment, and innovation. Few studies focus on evaluation combining development levels. This study uses the entropy weight TOPSIS method to build an urban high-quality development level indicator system with “innovation, coordination, greenness, openness, and sharing” as the indicators, comprehensively measuring the high-quality development level of 31 cities in the middle reaches of the Yangtze River from 2010 to 2019 and analyzing the evolution of spatial distribution and autocorrelation. The results show that the high-quality development level of the urban agglomeration in the middle reaches of the Yangtze River varies greatly, and fluctuations are significant. The spatial distribution also shows an evolution from belt-shaped agglomeration to point-shaped diffusion distribution, and the spatial autocorrelation shows a negative correlation. Finally, this paper proposes suggestions to promote high-quality development from three aspects: system coordination, industry coordination, and sustainability

Stackelberg Game Model of Railway Freight Pricing Based on Option Theory

In recent years, although rail transport has contributed significantly to the productivity of the Chinese economy, it has also been faced with the fierce competition and challenge from other modes of transportation, and therefore, freight-pricing issue has received more attention by researchers. In this paper, the rail freight option (RFO) based on option theory is proposed to study the optimal pricing decision of the railway transportation enterprise and contract customers’ optimal purchase decisions. To obtain an effective RFO contract, the railway freight contract transaction process is first analyzed. Then, the theoretical framework for the RFO contract trading is put forward in the railway freight market. Next, a two-stage Stackelberg game theoretic approach is presented based on the principle of utility maximization to achieve the optimal decision of RFO contract. Subsequently, the reverse reasoning method in dynamic programming is used to solve the optimal combination decision of the contract customer. Finally, the optimal pricing decision of RFO is discussed using Kuhn–Tucker conditions and Lagrangian function. The result shows that the railway transportation enterprise should pay more attention to the option strike price w1 in terms of maximizing system utility and achieving Pareto optimal

Research on PDA-based Predictive Maintenance System of CNC Machine Tools

Abstract: The research on the predictive maintenance system of CNC machine tools based on PDA is of great theoretical significance and practical application value. This paper studied PDA-based predictive maintenance system of CNC machine tools using predictive maintenance theory as a guide to obtain the work state of CNC machine tools in machining process. The corresponding acoustic emission sensors, acceleration sensors and speed sensors are installed on CNC machine tools, by which PDA collected the information of tool machining process. If collected data is found abnormal, the warning module sends the alarm information to the staff via email or SMS and monitors the work state of CNC machine tools. Based on HP iPAQ hx2490 with data acquisition card, the sensor and other hardware equipment, the structure of hardware platform is completed. Employing LabVIEW, the system modules including data acquisition, email warning, SMS warning, login, and report generation are developed. This paper carried out positive exploration on the design of PDA-based portable data acquisition platform, data communication, the early warning maintenance

High-Quality Development Evaluation and Spatial Evolution Analysis of Urban Agglomerations in the Middle Reaches of the Yangtze River

Urban agglomeration in the middle reaches of the Yangtze River is key to the rise of central China, and an important engine for the high-quality development of the Yangtze River economic belt. Research on urban agglomeration in the middle reaches of the Yangtze River focuses mainly on economic development, ecological environment, and innovation. Few studies focus on evaluation combining development levels. This study uses the entropy weight TOPSIS method to build an urban high-quality development level indicator system with “innovation, coordination, greenness, openness, and sharing” as the indicators, comprehensively measuring the high-quality development level of 31 cities in the middle reaches of the Yangtze River from 2010 to 2019 and analyzing the evolution of spatial distribution and autocorrelation. The results show that the high-quality development level of the urban agglomeration in the middle reaches of the Yangtze River varies greatly, and fluctuations are significant. The spatial distribution also shows an evolution from belt-shaped agglomeration to point-shaped diffusion distribution, and the spatial autocorrelation shows a negative correlation. Finally, this paper proposes suggestions to promote high-quality development from three aspects: system coordination, industry coordination, and sustainability

The Space–Time Evolution of the Coupling and Coordinated Development of Public Cultural Services and Cultural Industries: A Case Study of 31 Regions in China

The coordinated development of public cultural services (PCS) and cultural industries (CI) is conducive to sustainable regional development. Few studies focus on the coordinated development of PCS and CI. This study builds an evaluation index system for the coordinated development of PCS and CI and uses the entropy weight method, synchronous development model, coupling coordination model, and exploratory spatial data analysis method on 31 regions in China. It evaluates the synchronous development levels, coupling coordination levels, and spatial evolution characteristics of the coordinated development of PCS and CI from 2011 to 2020. The results are as follows: (1) The coordinated development level of PCS and CI has risen steadily. The leading type is dominant in space, with the leading type > synchronous type > lagging type. (2) The overall coupling degree is high. The high-level coupling in space is dominant. (3) The degree of coupling coordination has improved. Regions with good spatial and high-quality coordination are concentrated in the eastern, central, and coastal areas. (4) The coordinated development of PCS and CI shows positive spatial correlation agglomeration. The degree of agglomeration is increasing, mainly high high, forming an important growth region in the Yangtze River Delta economic region and its surroundings. Finally, we propose policy recommendations for the coordinated development of PCS and CI, and provide new ideas for the collaborative development of PCS and CI in China