Low Coupling Degree Research Articles

Photoexcited States Dynamics on Cu(II) Porphyrines-Nanographenes Dyads

Donor-acceptor systems have garnered significant attention in the fields of semiconducting materials and light harvesting.1 Particularly intriguing are porphyrin diads, wherein porphyrins are covalently bonded to nanographenes, forming a dyad with an expected electron transfer from the porphyrin to the nanographene. In our study, we leverage the excellent charge transport properties of Hexabenzocoronene (HBC) in combination with the superior light harvesting capabilities of Cu(II) porphyrins.The steady-state absorption spectra of the dyads exhibit a linear combination of HBC and porphyrin spectra, suggesting a low degree of electronic coupling in the ground state. Femtosecond optical transient absorption spectroscopy (TAS) has been employed to investigate the dynamics of photoexcited states. The TAS spectrum of the dyad displays a first derivative shape of the steady-state absorption, indicative of a photoinduced electron transfer within the system.2 These findings underscore the potential application of these systems as donor-acceptor systems, wherein the Cu(II) porphyrine serves as the source, transferring electrons to the HBC nanographene. This points towards promising applications of this system in photovoltaic devices. Figure 1. A) Cu(II) porphyrine B) Cu (II) porphyrine, HBC and Cu(II) porphyrine-HBC dyad absorption spectra C) Cu (II) porphyrine with C-H chains, HBC and Cu(II) porphyrinewith C-H chains-HBC dyad absorption spectra D)u (II) porphyrine with C-H chains.______________________________________________[1] H. Imahori, T. Umevama, Journal of Physical Chemistry C 2009, 113, 9029–9039.[2] Shengqiang Xiao; Mohamed E. El-Khouly; Yuliang Li; Zhenhai Gan; Huibiao Liu; Li Jiang; Yasuyuki Araki; Osamu Ito; Daoben Zhu J. Phys. Chem. B 2005, 109, 8, 3658–3667 Figure 1

Study on the coupling vibration characteristics of vertical unit and plant of large underground pumping station for water transfer project

Abstract To investigate the coupled vibration characteristics of vertical pumping unit and plant structure of large underground pumping station for water transfer project, the coupled vibration differential equations are established. The structure nodes of are simplified from horizontal direction and vertical direction respectively by force. The structural parameters and load parameters of the model are analyzed and calculated, and the vibration response of each node are calculated by solving the vibration differential equations. A spectral analysis of white noise is applied to the coupled model, and the natural frequencies and vibration structures of dominant vibration modals are obtained. Research indicates that the vertical vibration modes of the system exhibit a relatively low coupling degree with the plant structure. The shaft system and the plant structure mainly display combined vertical vibrations, while the plant structure predominantly exhibits independent vertical vibrations. This implies that vertical vibrations are jointly influenced by shaft system stiffness and plant structure properties. In horizontal vibration modes, a strong coupling characteristic is observed between the upper structure of the pump station unit and the plant structure. This is primarily manifested as coupled vibrations between the support and the plant structure, which are collectively influenced by support constraints, shaft system stiffness, and plant structural properties.

Research on the spatio-temporal coupling relationship between agricultural green development efficiency and food security system in China

Food security and agricultural green development are fundamental issues concerning the survival of mankind. To realize the coordinated development of them is of great significance to promote the green transformation of agriculture and ensure national food security. However, few studies have analyzed the coupling relationship between agricultural green development and food security. Therefore, this study complements the research on the coupling relationship between them. First, we use the agricultural panel data of 31 provinces in China from 2010 to 2021 to measure the agricultural green development efficiency and food security level by Super-SBM model and entropy weight method. Then, the coupling relationship and spatiotemporal evolution of the two are analyzed by coupling coordination degree model. The results show that, first of all, China's agricultural green development efficiency and food security level have improved overall, but there are regional differences. Secondly, the degree of coupling and coordination between the two is significantly improved, and most provinces develop from the break-in stage to the coordination stage, and the regional differences are relatively reduced. Finally, Beijing, Shanghai and other developed areas are mostly of the lagging food security type, Liaoning, Shandong and other major grain producing areas have reached a high degree of coordination, while Tibet, Qinghai and other western regions are still in the break-in stage. According to the development situation of different regions, corresponding suggestions are put forward. For regions with lagging food security type, the government should give full play to the application of science and technology in agriculture and promote green and low-carbon planting technologies. For regions with low coupling and coordination degree, the government should improve support policies and build a collaborative operation system, adjust planting structure to improve land utilization rate and food security level. Finally, the government should work together to build agricultural industrial parks and give full play to the leading role of competitive provinces to achieve common development.

Dual‐Function Tactile Sensor with Linear Pressure and Temperature Perception at Low Degree of Coupling

Dual‐Function Tactile Sensor with Linear Pressure and Temperature Perception at Low Degree of Coupling

Study on the Spatial and Temporal Evolution of High-Quality Development in Nine Provinces of the Yellow River Basin

High-quality development (HQD) is a positive initiative in China to promote sustainable development. Promoting HQD in the Yellow River Basin (YRB) is a major national strategy for China. The YRB is an important ecological barrier and economic zone in China, which comprises nine provinces, including Qinghai, Sichuan, Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi, Henan and Shandong. The objective of this paper is to provide a comprehensive evaluation of the HQD of the nine provinces in the YRB. It clarifies the basic connotation of HQD and constructs a comprehensive evaluation index system for HQD according to the principles of comprehensiveness, distinctiveness, openness, refinement and feasibility. The comprehensive evaluation index system includes four dimensions: economic development, technology innovation, society and livelihood, and ecological security, which contain 28 secondary indicators. The combined method of coupling development and entropy weight termed the “technique for order preference by similarity to an ideal solution (TOPSIS)” was selected to make a comprehensive evaluation of the HQD of the nine provinces in the YRB from the time dimension and the space dimension, respectively. It was found that there are still problems, such as the differentiation of HQD, the low comprehensive development degree (CDD), and the low development coupling degree (DCD) in some provinces.

Dual‐Function Tactile Sensor with Linear Pressure and Temperature Perception at Low Degree of Coupling

Multiinformation tactile perception is highly important for detecting the change of external environment and realizing the compliant control of the robot. However, the integration of dual‐mode or multimode sensors with low coupling remains a challenge. Herein, a dual‐function tactile sensor with linear pressure and temperature perception is reported. The pressure detection part contains the pyramid conductive film and flexible hemispherical electrode, which works as the piezoresistive material. A spiral nickel film works as a temperature‐sensitive material for sensing the temperature of objects during approaching and while contacting. As a result, the dual‐function sensor can detect the pressure in 0–100 kPa with a sensitivity of 11.5 kPa−1, while the temperature is in 25–65 °C with a sensitivity of 0.0032 °C −1. To be state of the art, the tactile sensor array is used for an active safety control of robotic arms, which can realize the perception and timely avoidance of sudden changes in external temperature and object collisions.

Spatial–Temporal Patterns and Coupling Characteristics of Rural Elderly Care Institutions in China: Sustainable Human Settlements Perspective

With rapid urbanization, more and more rural young adults are moving into towns and cities on a large scale, while the elderly are largely left behind in rural areas. The number of elderly people living alone, disabled and handicapped in rural areas is increasing, adding to the already weak rural elderly problem and increasing the pressure on the governance of rural elderly risks. The sustainable development of elderly care institutions is an important element in tackling the rural elderly problem and a key aspect of managing the rural elderly problem. The article uses data on rural aged-care institutions in 276 Chinese cities from 2010–2016 to construct comprehensive evaluation indicators for the development of rural aged-care institutions, and uses a combination of hierarchical analysis, composite score method, Theil index and coupling coordination model to reveal the spatial and temporal patterns and coupling characteristics of the development of rural aged-care institutions. The study concludes that: (1) From the time series change, the comprehensive score of rural elderly institutions shows a “fluctuating” change process, and there are significant differences in the development of each secondary indicator. (2) In terms of spatial and temporal patterns, the overall scores of rural elderly institutions, hard environment scores, soft environment scores and service recipients scores show a clear “gradient” in the east, middle and west. (3) In terms of regional differences, the Theil index for rural elderly care institutions is from high to low: Hard environment > service recipients > soft environment > overall score. From the decomposed Theil index, the intra-group differences of rural aged-care institutions are much larger than the inter-group differences, and the intra-group differences of the Theil index of the four major regions generally show a narrowing trend, with the intra-group differences of the eastern region being higher than those of the western region, those of the western region being higher than those of the central region, and those of the central region being higher than those of the northeastern region. (4) In terms of coupling coordination, the coupling degrees of the four major regions all exceed the low-level coupling stage index and are in the antagonistic stage or the grinding stage, and the coupling degrees of the four major regions are, in descending order, central region > eastern region > northeastern region > western region. The coupling coordination degree of the four major regions from high to low is: Eastern region > central region > northeastern region > western region. Based on the empirical analysis, the article proposes a model path for the sustainable development of rural elderly institutions in three aspects: Coordinated development, coupled development and sustainable development, in view of the unbalanced regional development of rural elderly institutions and the low degree of coupling and coordination between the soft and hard environments.

Study on the coupling problem of coordinated development of economy–energy–environment–technology system in Northeast China

Under the strategy of “Northeast Revitalizing”, Northeast China must correctly handles the coupling relationship of coordinated development among economy, energy, environment, and technology if it insists on the concept of green development. In this paper, by establishing an appropriate evaluation index system and introducing ”kernel function density” analysis method, the coupling problem and it’s time evolution characteristics of the coordinated development of the economy–energy–environment–technology of Liaoning Province, Jilin Province, Heilongjiang Province and Inner Mongolia Autonomous Region in Northeast China were studied. It was found that the coordination degree of the quaternary systems was between 0.71 and 0.97, and it was good. The development degree was between 0.25 and 0.58, and it was very bad. The ”weakness” of low development degree results in the low coupling degree (between 0.46 and 0.70) of the quaternary system. The coordination degree of the quaternary systems in Northeast China was increasing year by year, and the differences between provinces (regions) were also shrinking. The development degree generally presented ”wave” fluctuation characteristics, and the regional difference showed an increasing trend. The coupling degree of Heilongjiang Province, Jilin Province and Liaoning Province basically maintained a steady state of improvement, and Inner Mongolia Autonomous Region improved significantly after 2017. Finally, the paper put forward some countermeasures and suggestions to improve the coupling degree of the coordinated development of economy, energy, environment and technology in Northeast China, so as to provide reference for the revitalization of Northeast China.

Research on the Coupling and Coordination of Systems of Citizenization, Regional Economy, and Public Service in China from the Perspective of Sustainable Development

Based on the perspective of sustainable development, this paper introduces the circular economy dimension into the economic system, the ecological environmental protection dimension into the public service system, and constructs index evaluation systems for citizenization, regional economy, and public service, respectively. Then, the paper establishes a coupling coordination model to study the mutual relationship between citizenization, regional economy, and public service at provincial levels, so as to promote the sustainable development of population, economic society, and resource environment. The main research conclusions are as follows: (1) the level of citizenization is generally low, and the dimensions of income and social security are weak; (2) the development trend of circular economy in the eastern regions is better than that in other regions; (3) the “Citizenization, Regional Economy, Public Service” System has an overall low coupling and coordination degree and it shows a trend of “high in the east and low in the west”; (4) the contradictory characteristics between the systems vary greatly by province. Most of the provinces’ systems of the regional economy and public service lag behind their citizenization and some developed provinces have a lag in their citizenization systems. In order to promote a high-quality coordinated development between the systems of citizenization, regional economy, and public service, a sustainable development path that adapts to local conditions must be sought. It should focus on improving the social security level of rural-to-urban migrants, establishing a circular economy, and strengthening the construction of an ecological environment.

Crop Water Requirement and Utilization Efficiency-Based Planting Structure Optimization in the Southern Huang-Huai-Hai Plain

Optimizing planting structure that balances both high yield and water resources shortage is essential for developing efficient water-saving agriculture. To provide insights about the relationship between planting structure optimization and water resource constraint, crop water requirement, precipitation coupling degree, gross total water requirement and irrigation project metrics were calculated and analyzed with the dataset collected from 16 locations in Xuchang City, China. The strategy of reducing the planting proportion of high water-consumption crops and increasing low consumption and high precipitation coupling degree crops was adopted to determine a suitable water-saving planting scheme based on the IQR (interquartile range) method. Evapotranspiration had a decreasing trend from northwest to southeast areas. There were positive correlations between gross total water requirement (GTWR) and annual total yields (r = 0.825, p = 0.002), and between GTWR and proportion of vegetable planting areas (PVPA) (r = 0.734, p = 0.0101). The GTWR was negatively correlated with the ratio of water-saving irrigated areas to effective irrigated areas (RSEA), proportion of wheat planting areas (PWPA) and proportion of bean planting areas (PBPA), with coefficients of −0.787, −0.936 and −0.828, respectively. The planting proportion of winter wheat, summer maize, vegetables and flowers decreased by 8.8%, 25.8%, 16.2%, and 28.7%, respectively, while oil-beans and tubers increased by 62.4% and 95.6%, respectively. The irrigation water consumption was reduced by 5.2%, saving 3.25 × 107 m3 irrigation water without sacrificing economic benefits after adjusting for the whole region. Consequently, precipitation coupling degree, water-saving technology and historical planting habits should be considered when optimizing cropping distributions. This research provided a new theoretical basis and comprehensive approach for agriculture irrigation water management and regional planting structure optimization from a realistic perspective.

A traffic status evaluation method of expressway merging area based on improved coupling theory

In order to further reveal the law and characteristics of on-ramp traffic flow into the main line of expressway road and make up for the deficiency of traditional inflow model which cannot evaluate the state of merging area, the coupling theory in physics was introduced. First of all, “gap acceptance” model was adopted to describe the operation law of merging area, and the relationship between important parameters such as flow rate and headway was analyzed by using discrete probability function. Second, coupling degree and coupling coordination degree were put forward, after analyzing the characteristic under the premise of the merging area, using a large amount of measured data regression analysis of the traffic, location speed and the headway of parameters in the coupling. The coupling theory was modified, the coupling function evaluation model of confluence area was established, and the interaction and influence between main line and ramp system were quantitatively analyzed and evaluated. Finally, the model is verified by the actual observation data of Shanghai expressway. The results indicate that in the early peak period, the coupling coordination degree is about 0.36 and 0.4, which is in a moderate coordination stage. During the peak flow period, the coupling coordination degree is only 0.28, which is in a low degree of coordination coupling and the system is relatively disordered. In nonpeak hours, the coupling coordination degree is around 0.83, which is in an extremely coordinated state. The error between the flow calculated by the coupling theory and the data observed in the field is generally 4.2%–12.8%, which indicates that the results of the running status evaluation of merging area by using this model are reliable.

Demystifying process-level scalability challenges in fashion remanufacturing: An interdependence perspective

The purpose of this paper is to determine how process-level challenges can be solved in order improve scalability of fashion remanufacturing. In order to do so, and prescribe solutions, the paper first conducts a systematic literature review to reveal three categories of process-level challenges that are related to sourcing of input material, process throughput time, and skillset requirement. These categories further guided us in conducting case study with a Swedish charity-owned fashion remanufacturer for exploring how the challenges are addressed and solved in order to achieve process-level scalability. First, our study reveals a systematized approach to determine product-process categories defined by production volume and degree of remanufacturing. Second, by exploring the process-level challenges of six different remanufactured product groups in the case study organization we identify process-level requirements for scalability, and challenges when these are unmet. The findings show that in fashion remanufacturing (particularly disassembly and reassembly), low degree of coupling, high level of formalization of activities and low skill specificity can be ways to attain process-level scalability. Overall, this highlights the need to build lower interdependence between disassembly and reassembly during fashion remanufacturing.

Coupling between Carbon Efficiency and Technology Absorptive Capacity—A Case Study of the Yangtze River Economic Belt

Regional carbon efficiency (CE) improvement is critical to China’s “taking concerted efforts to achieve ecological protection” strategy in the Yangtze River Economic Belt (YREB) and their program to build a leading demonstration belt for ecological civilization. This study applied the super efficiency slacks-based measure to calculate the regional differences and evolution characteristics of the YREB’s CE from the year of 2006 to 2017. It also constructed a coupling evaluation model to empirically analyze the interactions between CE and technology absorptive capacity (TAC). The results showed that (1) the CE for all YREB provinces followed a “U-shaped” trend. TAC generally increased and incrementally decreased in the sequence of the upper stream, middle stream, and downstream. The gap among the downstream, upper stream, and middle stream increased; (2) coupling between the CE and TAC for the YREB provinces can be characterized as a relatively stable medium to low coupling degree and medium-to-high coordination degree. To improve coupling and achieve balanced, sustainable development in the YREB, this study proposes several measures, including promoting balanced, high-quality economic development, building the YREB talent pool, appropriately guiding foreign capital flows, implementing the strategy of driving economic development through innovation, and launching the network for coordinated technological innovation in YREB.

µBIGMSA-Microservice-Based Model for Big Data Knowledge Discovery: Thinking Beyond the Monoliths

Enterprise thrives on software applications that are built to fulfil the core business requirements. A single business application can offer a cluster of capabilities to generate value from processing huge amount of data often termed as Big Data. The time-based requirements of these applications are satisfied frequently by applying monolithic approaches with increased complexity and less scalability. Traditional approaches for Big Data Analytics suffer from overpriced, excessive and irrelevant data transfer owing to the constricted coupling amongst computing resources and data processing logic. Service-oriented approach came into existence as a new paradigm to enable applications to be rendered as service for better flexibility and scalability. Service orientation architecture avoids monolithic style but web services, one of its major implementation encourages monolith development of software application. Thus building a scalable, robust, resilient, cost-effective and optimum solution is one of the major requirements for outsized data. New software development style Microservices offer low degree of coupling and smaller size. This work reviews the existing and prevalent approaches like monolithic architecture in this area along with their drawbacks. This work also proposes a generic microservice model µBIGMSA for handling Knowledge Discovery in Big Data. Reference applications are implemented using proposed model. The effectiveness of the proposed model is evaluated by comparing the reference application with the monolithic application using various software metrics.

An Exploration of a Synthetic Construction Land Use Quality Evaluation Based on Economic-Social-Ecological Coupling Perspective: A Case Study in Major Chinese Cities.

Recently, with the rapid increase of urban population and industrial agglomeration, the price of construction land has increased, and construction land has become increasingly scarce. Therefore, how to improve the construction land use quality (CLUQ) becomes more and more important. The purpose of the study is to evaluate CLUQ in China’s major cities and to analyze the dominant obstacle factors for quality improvement in order to provide policy advice for construction land management. This study adapts the data from 2014 to 2016 and constructs the evaluation framework of CLUQ involving economic quality, social quality, and ecological quality of construction land to evaluate and analyze CLUQ with the synthetic evaluation model, coupling evaluation model, and obstacle diagnosis model (ECO model). This study shows that the synthetic CLUQ of 23 cities out of 36 major cities in China shows a general increasing state. The economic quality of 26 cities out of 36 major cities in China has increased, while the social and ecological quality of 20 out of 36 major cities in China has decreased. In terms of spatial characteristics, the synthetic quality in the east and southwest of China is relatively high; in terms of spatial trend, the synthetic quality in longitude increases from west to east, and it shows an inverted U-shaped state in latitude. Moreover, economic development is the main obstacle factor for the improvement of CLUQ in Hohhot, Lanzhou, Urumqi, and Changchun. Social development results in the CLUQ lagging in Beijing, Guiyang, Shanghai, Xining, and Chongqing. Ecological development has a negative impact in that of Harbin, Qingdao, and Wuhan. Furthermore. The improvement of CLUQ lies in the coupling and coordinated development of economic, social, and ecological quality. For those with a low coupling degree, the targeted suggestions are given for different types based on city’s quadrant distribution.

Mechanism design and kinematics simulation of 3-DOF parallel mechanism with low coupling degree

According to the topological design theory of parallel mechanism(PM) based on the position and orientation characteristic(POC), a new PM with two translational degree of freedom(DOF) and one rotational DOF (2T1R) was proposed. The topological characteristics of the PM was analyzed, including POC set, DOF and coupling degree. Based on analytic method, the solving modeling was established, and the forward and inverse solutions were obtained. Then the correctness of the position solution was verified by Matlab. Velocity and acceleration formulas of PM were calculated by Jacobian matri, and simulation curves of velocity and acceleration was put forword. Kinematic analysis shows that the 2T1R PM has both translational and rotational characteristics, moreover, the moving platform has stable output and good dynamic characteristics.

Theoretical investigation of intermolecular hydrogen bond induces fluorescence quenching phenomenon for Coumarin-1

In this work, density functional theory and time-dependent density functional theory were performed to investigate intermolecular hydrogen bond (H-bond) effect on Coumarin-1 (C1). The optimized geometric structures of C1 in acetonitrile and methanol (MeOH) revealed that C1 exhibits planar configuration in ground state and locally excited (LE) state. Due to intermolecular H-bond interaction between C1 and MeOH, twisted intramolecular charge transfer (TICT) state with twist configuration exists in excited state for C1–MeOH. The apparent variation of characteristic group frequencies and intensities for IR spectra is ascribed to dramatic charge density changes. Compared with molecular orbitals of LE state, the low charge coupling degree of C1–MeOH in TICT state is induced by twist configuration in TICT state. Indeed, such low charge coupling degree induced TICT state is nonluminous that responsible for low fluorescence quantum yield of C1–MeOH. We not only provide a comprehensive understanding of TICT state deactivation process but also benefits to design new environment-sensitive probe.

Application of Improved PSO-BP Neural Network in Cold Load Forecasting of Mall Air-Conditioning

A combination of JMP, PSO-BP neural network, and Markov chain which aims at the low correlation between input and output data and the error of prediction model in the PSO-BP neural network prediction model is proposed. First, the JMP data processing software is used to process the input data and eliminate the samples with low coupling degree. Then, obtaining the cooling load prediction results relies on the training from the PSO-BP neural network. Finally, the final prediction results will be generated by eliminating the random errors using the Markov chain. The results show that the combination of the prediction methods has higher prediction accuracy and conforms to the change rule of the cooling load in shopping malls. Besides, the combination fits the actual application requirements as well.

Reduction of intergranular exchange coupling and grain size for high Ku CoPt-based granular media: Metal-oxide buffer layer and multiple oxide boundary materials

Investigation of magnetic properties and microstructure of granular media with various multiple oxides as the grain boundary material is reported. Saturation magnetization (Ms), uniaxial magnetocrystalline anisotropy (Ku), and magnetic grain diameter (GD) of the granular media show linear correlation with volume weighted average for melting point (Tm) of each oxides (Tmave). Ku of magnetic grains (Kugrain) shows a trade-off relation with GD that it is a big challenge to satisfy both high Kugrain and small GD by only controlling Tmave. To obtain a granular medium with appropriate Kugrain, GD, and low degree of intergranular exchange coupling, the combination of Tmave control of grain boundary material by mixing oxides and employment of a buffer layer are required. Here the degree of intergranular exchange coupling is estimated from the slope of M-H loop at around coercivity (α). By applying this technique, a typical granular medium with Kugrain of 1.0×107 erg/cm3, GD of 5.1 nm, and α of 1.2 is realized.

Compositional Reservoir-Flow Simulation for Organic-Rich Gas Shale

Summary A new-generation compositional reservoir-flow-simulation model is presented for gas-bearing organic-rich source rocks, including convective/diffusive mass-balance equations for each hydrocarbon component in the organic (kerogen), inorganic, and fracture continua. The model accounts for the presence of dispersed kerogen with sorbed-gas corrected dynamic porosity. The Maxwell-Stefan theory is used to predict pressure- and composition-dependence of molecular diffusion in the formation. The equations are discretized and solved numerically by use of the control-volume finite-element method (CVFEM). The simulation is derived from a new multiscale conceptual flow model. We consider that kerogen is dispersed at a fine scale in the inorganic matrix and that it will be the discontinuous component of total porosity at the reservoir-simulation scale, which could be up to six orders of magnitude larger. A simple mass-balance equation is introduced to enable kerogen to transfer gas to the inorganic matrix that is collocated in the same gridblock. The convective/diffusive transport takes place between neighboring gridblocks only in the inorganic matrix. The simulation results show that the multiscale nature of the rock is important and should not be ignored because this could result in an overestimation of the contribution of the discontinuous kerogen. We also observe that although adsorbed fluid could contribute significantly to storage in the shale formation, its contribution to production could be severely limited by the lack of kerogen continuity at the reservoir scale and by a low degree of coupling between the organic and inorganic pores. The contribution of the Maxwell-Stefan diffusion to the overall transport in the shale formation increases as the inorganic matrix permeability is reduced because of pressure decline during production.