Key Problem Research Articles

Research progress and key scientific problems of traditional Chinese moxibustion

Research progress and key scientific problems of traditional Chinese moxibustion

Coupling resonance of signal responses induced by heterogeneously mixed positive and negative couplings in cognitive subnetworks

How weak external signals are detected in cognitive subnetworks is one of the key problems to understand how brain functions work. So far, most studies on signal responses are focused on artificial complex networks and it is found that a topological resonance can be induced by the feature of scale-free networks, but little attention has been paid to real brain networks, especially the cognitive subnetworks responsible for signal responses. Herein we address this problem in real brain networks but do not find such a topological resonance, indicating that scale-free is not the key feature of brain networks. Surprisingly, we find a novel resonance effect of signal response induced by heterogeneously mixed positive and negative couplings and thus name it as coupling resonance of signal responses, which explains the mechanism of how brain networks, especially the cognitive subnetworks, detects weak signals. We investigate this coupling resonance in the cases of both heterogeneous couplings and heterogeneous oscillators and find that there is an optimal phenomenon on both the average and standard deviation of coupling strengths. Further, we confirm this coupling resonance in real cognitive subnetworks with weighted links. Finally, we provide a theoretical analysis to show that this coupling resonant comes from the coexistence of the two different local states of neighboring nodes.

A kinetic model for solving a combination optimization problem in ab-initio Cryo-EM 3D reconstruction.

Cryo-Electron Microscopy (cryo-EM) is a widely used and effective method for determining the three-dimensional (3D) structure of biological molecules. For ab-initio Cryo-EM 3D reconstruction using single particle analysis (SPA), estimating the projection direction of the projection image is a crucial step. However, the existing SPA methods based on common lines are sensitive to noise. The error in common line detection will lead to a poor estimation of the projection directions and thus may greatly affect the final reconstruction results. To improve the reconstruction results, multiple candidate common lines are estimated for each pair of projection images. The key problem then becomes a combination optimization problem of selecting consistent common lines from multiple candidates. To solve the problem efficiently, a physics-inspired method based on a kinetic model is proposed in this work. More specifically, hypothetical attractive forces between each pair of candidate common lines are used to calculate a hypothetical torque exerted on each projection image in the 3D reconstruction space, and the rotation under the hypothetical torque is used to optimize the projection direction estimation of the projection image. This way, the consistent common lines along with the projection directions can be found directly without enumeration of all the combinations of the multiple candidate common lines. Compared with the traditional methods, the proposed method is shown to be able to produce more accurate 3D reconstruction results from high noise projection images. Besides the practical value, the proposed method also serves as a good reference for solving similar combinatorial optimization problems.

Analysis of the development of China's fresh agricultural products e-commerce platform based on Marx's production and circulation theory

The key problem of agricultural production is to realize the value of agricultural products. At present, the actual circulation of agricultural products in China is restricted by various problems. In response to the question of how to better smooth the circulation system of agricultural products in the context of the normalized management of the epidemic and the digital economy, Chinese academics are currently more inclined to use economic principles to study and answer it. This paper uses an indirect research method, combined with the theory of production and circulation in Marxist political economy, to try to analyze the development direction of China's agricultural products circulation system under digital inclusion. The critical factor for advancing the transformation and upgrading of China's agricultural goods circulation system is in the reduction of circulation time and costs, hence enhancing the efficiency of agricultural product circulation. Hence, it is imperative to proactively cultivate novel rural e-commerce models alongside enhancing the conventional agricultural product circulation system. This entails encouraging diverse stakeholders to actively engage in the establishment of a contemporary agricultural product circulation system under government guidance, while also enhancing the organization and digitization of agricultural product distribution.

New approaches to determine the technological challenged of oil fields at the late stage of development

Background: The main problem of the process of field development in the later stages is the limitation of free funds associated with the decline in production and the corresponding decrease in the profitable part of enterprises. At the same time, the accumulated effect of critical production problems is manifested, for the solution of which in practice a significant amount of capital investments is required in different areas of field development.
 The late stage of development of fields is associated with a number of problems, the main of which are the deterioration of the structure of the reserves and the slow pace of their replenishment, low withdrawal rates and high water cut, frequent failure of ground equipment, technological limitations of the production infrastructure, the quality of construction and completion of wells, a short turnaround time of production wells affecting the wells’ operation coefficient, and insufficient coverage of production processes with digitalization.
 Aim: Considering the large amount of work involved in the oil production process (from geology to onshore infrastructure), an internal benchmarking analytical tool is needed to identify current and most common technological challenges, to focus scientific, technical and production personnel in a certain direction and develop a systematic approach to solving production problems. The purpose of this work is to develop such a tool
 Materials and methods: As the input data, historical data on the production, hydrocarbons reserves, the current technological parameters of underground and surface equipment of 12 oil fields of the group of the NK “Kazmunaygaz” JSC companies were used. 17 basic criteria were formed in the areas of geology, development, oil production, drilling and infrastructure, which served as the basis for internal benchmarking of oil fields.
 Results: As a result of this work, a tool was developed for the diagnosis of key production problems of KMG oil fields. The diagnostic chart is effective for determining zones of the spread of production problems both in one oil field and in all oil fields of KMG. This approach can be scaled to the level of oil fields and horizons.
 Conclusion: The developed internal benchmarking tool serves as the basis for the annual analysis of key problems of the oil fields of the group of the NC “KazMunaygaz” JSC companies and the formation of a long -term plan to solve key production challenges.

Design and optimization of dielectric metalens with quasi-periodic arrays

Metalenses have attracted a great deal of research interests due to the property of light controllability. How to enhance the focusing effect of metalens has always been a key problem that many researchers have been working on. In this paper, we propose a novel sub-dimensional resonance-based optimization method for dielectric metalens with golden angle spiral arrays. The waveguiding effect is first applied to the initial design of the quasi-periodic metalens through the defined equivalent period. Then the genetic algorithm is improved for adjusting the sub-dimensional structure of the initial metalens. The optimization results show that the peak intensity of central hot spot increases by 32 % while keeping the full width at half maximum (FWHM) almost unchanged. At the same time, the field intensity of side lobes around the hot spot decreases, which means that a potential way for high-contrast imaging is provided.

DESIGN AND IMPLEMENTATION OF AN AUTOMATED BUDGETING SYSTEM AT A MINING ENTERPRISE: THE CASE OF RG GOLD LLP

This article is aimed to investigate the process of designing and implementing an automated budgeting system at a mining enterprise in order to provide an overview of methods, tools and stages of implementation, as well as an analysis of the advantages and practical examples of using this system.The purpose of the research is to identify the features of the budget process and develop recommendations for the successful implementation of an automated budgeting system to improve fi nancial management and increase the effi ciency of a mining enterprise.Methodology. The following scientifi c methods were used in the study: comparative analysis; synthesis; methods of systematization and generalization, in-depth interview, SWOT analysis.Originality / value of the research. The value of this study consists in identifying the key problems of budgeting of industrial enterprises of the Republic of Kazakhstan, developing a methodology for designing and implementing an automated budgeting system for the gold mining company RG Gold LLP. The introduction of an automated budgeting system at the enterprise has made it possible to reduce the time spent on consolidating data when forming budget applications, reduce the risk of the human factor, increase the time for forecasting and modeling the budget for making management decisions and increasing competitiveness in the market.Findings. Based on diagnostics, SWOT analysis of the current budgeting system in the fi nancial management system of RG Gold LLP and an expert survey to identify its limitations, user needs for the automation process were determined.A model product for automation of the budgeting system with functional testing of the budget campaign of RG Gold»LLP for 2024 has been designed.The automated budgeting system of Anaplan RG Gold LLP has been confi gured and training programs for its users have been developed.The potential impact of the Anaplan budgeting automation system on accelerating the process of making strategic fi nancial and managerial decisions and increasing labor productivity by saving time, labor and fi nancial resources in RG Gold LLP were estimated.

Lead‐Free All‐Inorganic Cesium Bismuth Iodide‐Based Perovskite Solar Cells: Recent Advances, Current Limitations, and Future Prospects

Remarkable achievements have been made in the development of perovskite solar cells (PSCs) with a rapidly boosting rate of power conversion efficiencies (PCEs) from 3.8% to 26.1%. Nevertheless, the toxicity of lead (Pb) elements and the hygroscopicity of organic cations in high‐efficiency PSCs severely hamper the commercialization of this technology. Consequently, Pb‐free all‐inorganic PSCs have received increasing attention recently to resolve the above‐mentioned toxicity and instability problems. Among various Pb‐free all‐inorganic halide perovskites, cesium bismuth iodide (CBI)‐based perovskites have gained particular attention as light absorbers in PSCs due to the tunable/small bandgaps, long carrier diffusion length/lifetime, and superb sunlight absorption coefficients. Nevertheless, the PCEs of CBI‐based PSCs are still far away from Pb‐based organic–inorganic counterparts because of the low structural dimensions and inferior perovskite film quality. Herein, the recent advances of CBI‐based perovskites as light‐absorbing materials in Pb‐free all‐inorganic PSCs are reviewed by emphasizing the distinct structural/optical/electronic properties and currently existing limitations. Additionally, several distinct strategies to boost the PCEs and robusticity of CBI‐based PSCs are presented. Finally, the unsolved key problems and future directions of CBI‐based PSCs are proposed, aiming to provide important insights for the further development of CBI‐based PSCs to realize sustainable, nontoxic, high‐performance perovskite photovoltaics.

Seismic Behavior of Demountable Self-Lock Joint for Middle Column Connection in Modular Steel Construction

The use of modular steel construction (MSC) achieves a minimum of on-site work and the potential for removability and reuse. In order to realize the overall disassembly of module buildings and the rapid off-site reconstruction after disassembly, special requirements are put forward for the joints of MSCs. The existing joints of MSCs have some problems, such as the difficulty in the erection of the joints for middle column connection and their inability to be reused. In order to solve these key technical problems, an improved version of the demountable self-locking joint is proposed based on the previous plug-in self-locking joint. For this new type of joint, a full-scale test consisting of four specimens was carried out. The results of functional tests verify that the joint has good demountability. The seismic behavior of the joint under seismic load was investigated by cyclic loading tests. Then, finite element (FE) models were developed and validated through the test results. The results of finite element parameter analysis show that joint boxes are very important to the initial stiffness of this kind of joint, but the thickness of the joint box and the diameter of the stud have little influence on the seismic behavior of the joint.

Смарт-контракты в российском праве: отсутствие определения и вызванные им юридические и практические проблемы

This article examines the lack of a clear legal definition of a smart contract in Russian legislation and its impact on the legal status, interpretation, regulation and practical implementation of this technology. The authors consider various attempts to introduce the term ‘smart contract’ into Russian legislation and analyze the proposed definitions of a smart contract from various parties. The key legal and practical problems associated with the use of smart contracts are highlighted, such as uncertainty of status, difficulties of interpretation, possible failures, limited flexibility, impossibility of changes and procedures for concluding. The article also emphasizes the need to develop a balanced and clear legal regulation of smart contracts in Russia, taking into account the technical and legal aspects of this technology and ensuring the protection of the interests of all parties.

The Impact of DNA Databases on the Investigation of Crimes

This study aims to establish the significance and impact of using DNA data in forensics. The study employed the anamnestic method, descriptive analysis, and forecasting. The conducted research identified the key problems of creating and using DNA databases, including insufficient logistical and laboratory support, understaffing, lack of special legislation, low level of security, slow filling of databases, disregard of the public position, and the need to establish international cooperation. It was established that DNA analysis enables identifying the identity of the deceased or a person who cannot identify himself; determining the number of persons at the crime scene; establishing whether DNA traces belong to a suspect; establishing a connection between several crimes by matching DNA samples taken from the scene; establishing those accused of crimes. It is proposed to increase the effectiveness of law enforcement activities through the development of an International Strategy for the Influence of the Use of DNA Databases and ensure international cooperation on the exchange of DNA information in forensics.

Legal and Ethical Regulation in Slovakia and Its Relation to Deliberative Communication

The offered social-scientific analysis is based on a critical discussion of key problems present in the Slovak media environment, such as the ethical self-regulation of the media, freedom of expression, the right to obtain information, or the legal protection of the sources of information. The study also refers to available scholarly sources and the previously published body of knowledge to assess the development of the media system in Slovakia over the past 30 years, outlining the country’s (in)ability to foster deliberative communication and democracy. The results suggest that the legal and ethical aspects of the Slovak media system do support some of the principles of deliberative communication, specifically freedom of expression and free access to information; however, free speech is not sufficiently confronted with the boundaries of protecting privacy and human dignity to prevent defamation and hate speech. Media autonomy based on the possibility of self-regulation is not sufficiently developed either. A serious problem is the lack of transparency in the media.

Earth‐Abundant Fe‐Mn‐Based Compound Cathodes for Sodium‐Ion Batteries: Challenges and Progress

AbstractSodium‐ion batteries (SIBs) with high energy/power density and low‐cost characteristics are deemed to be one of the best replacements to lithium‐ion batteries for utilizing in large‐scale electric energy storage (EES) devices. Fe‐Mn‐based cathode materials take the leading position in realizing high‐performance SIBs because of their high capacity, environment‐friendly, earth abundant, and low‐cost features, exhibiting huge commercial potential. However, the energy density and cyclic stability are still limited so far, considering the increasing demands for practical applications. In this review, aiming to better understanding the research level and currently existed sore points, the research progress is overviewed for several types of Fe‐Mn‐based cathode materials, including layered oxides, polyanionic compounds and Prussian blue analogues, and refine the electrochemical storage mechanism and structure–performance relationship. Finally, the representative electrochemical performances of these three kinds of cathode materials is summarized, compare the advantages and disadvantages of various materials, point out the existing key scientific problems of these materials, and propose the direction of development in near future. This review makes a thoroughly understanding for Fe‐Mn‐based cathode materials, providing new guidance for future research on SIBs toward real‐world applications.

Loose monetary policy and corporate NPD R&D innovation

Based on the data of Chinese listed companies from 2006 to 2022, this paper shows that loose monetary policy will significantly promote enterprises' NPD innovation. At the same time, financial subsidies can strengthen this promoting effect. Nowadays, policy support is to alleviate the problem of insufficient innovation ability of enterprises from the perspective of external financing, it does not fundamentally solve the lack of innovation ability of enterprises, and has become the key problem of attention and research in academic circles. However, existing research pays less attention to the essence of improving NPD R&D innovation readiness, especially how to stimulate the innovation motivation of management is the lack of in-depth research to solve the fundamental problems of insufficient innovation investment and low innovation quality.

The future of sleep apnea management: we can either ride the bus or drive it

This consensus conference report summarizes discussions on sleep apnea care and management. Our goal is to simplify the journey to optimize success for individuals at risk of obstructive sleep apnea and to facilitate diagnostics, monitoring and communication among the entire healthcare team including patients, primary care physicians, sleep specialists, sleep dentists and other key providers. The statement identifies five key problems or unmet needs and contemplates four potential future directions.

Seizing unconventional arbitrage opportunities in virtual power plants: A profitable and flexible recruitment approach

A virtual power plant (VPP) is typically a collection of distributed energy resources (DERs) aggregated by an energy service provider (ESP). However, recruiting DER owners to participate in a VPP is challenging. Therefore, we propose a profitable and flexible VPP recruitment-participation approach that incorporates both long-term regular recruitment and short-term casual recruitment. Casual recruitment caters to ambitious DER participants, consisting of fair and bet-on modes. The latter establishes a set of pre-determined payoff conditions, the fulfillment or non-fulfillment of which confers the participants a contractual right to get compensation from the ESP. To ensure the success of the proposed recruitment approach, we address two key problems. First, we introduce a new index, unconventional arbitrage opportunity (UAO), for evaluating future profits and propose a conditional time series generative adversarial network to predict UAO with weather conditions. Second, we introduce a payoff allocation method that combines fairness and incentives to motivate casual DER participants. The incentive coefficients are optimized using an improved deep reinforcement learning algorithm. Case studies are conducted to verify the proposed recruitment-participation approach, the effectiveness of the UAO prediction model, and the optimized incentive coefficients.

Application of Bayesian method for mining-induced tremors: A case study of the Xinjulong coal mine in China

Mining-induced tremor is a dynamic phenomenon occurring during the fracturing or slipping of rock and coal mass in coal mines, and the tremor mechanism is one of the key problems in the field of rockburst. The Bayesian inversion method can more accurately analyse the source rupture type under the premise of considering waveform data and model errors. First, we added different noise levels to the waveform and determined filtering parameters based on the spectrum. The rationality of the Bayesian inversion was verified by observing the focal mechanism solution. Finally, a total of fourteen mining-induced tremors were selected, and the parameters of the moment tensor (MT), type of rupture, and fault plane solutions were obtained. The results demonstrate that (1) the tremor events in the roof are mainly tensile/shear failure, and compression failure mainly occurs in the coal seam. (2) Events on the floor are closely related to gob and mining activities. (3) The rupture form of the events near the tectonic region is more complex, and the fault plane solutions (strike, dip, and slip) were obtained by MT conversion. (4) The relation between rockbursts and mining-induced tremors is discussed by analysing events 1# and 14# that occurred in the Xinjulong coal mine. These research findings can provide a reference for the analysis of source parameters and rupture forms of mining-induced tremors.

Explainable text-based features in predictive models of crowdfunding campaigns

AbstractReward-Based Crowdfunding offers an opportunity for innovative ventures that would not be supported through traditional financing. A key problem for those seeking funding is understanding which features of a crowdfunding campaign will sway the decisions of a sufficient number of funders. Predictive models of fund-raising campaigns used in combination with Explainable AI methods promise to provide such insights. However, previous work on Explainable AI has largely focused on quantitative structured data. In this study, our aim is to construct explainable models of human decisions based on analysis of natural language text, thus contributing to a fast-growing body of research on the use of Explainable AI for text analytics. We propose a novel method to construct predictions based on text via semantic clustering of sentences, which, compared with traditional methods using individual words and phrases, allows complex meaning contained in the text to be operationalised. Using experimental evaluation, we compare our proposed method to keyword extraction and topic modelling, which have traditionally been used in similar applications. Our results demonstrate that the sentence clustering method produces features with significant predictive power, compared to keyword-based methods and topic models, but which are much easier to interpret for human raters. We furthermore conduct a SHAP analysis of the models incorporating sentence clusters, demonstrating concrete insights into the types of natural language content that influence the outcome of crowdfunding campaigns.

The 60 nm gold nanoparticles improve qPCR amplification efficiency through specific palindromic sequences (GGATCC or ACCGGT) in primers

BackgroundPolymerase chain reaction (PCR) technology and quantitative real-time PCR (qPCR) technology are widely used in clinical diagnosis and research, but amplification efficiency and sensitivity are still key problems for researchers. An increasing number of reports show that gold nanoparticles (AuNPs) can be used to improve the sensitivity and amplification efficiency of PCR. Here, we found that 60 nm gold nanoparticles with a positive charge (60 nm- Au+) can enhance the amplification efficiency of qPCR. MethodsMouse DNA was extracted by the alkaline lysis method. Primer 5.0 software was used to design primers and mutation primers, and the DNA fragments were obtained by the method of synthesizing plasmids. The qPCR was applied to amplify target gene fragments. ResultsThe amplification efficiency of qPCR was improved by about 1.828 times in the experimental group with 60 nm- Au+ compared with the control group without 60 nm- Au+. The primer pair contains a specific palindromic sequence (GGATCC or ACCGGT). And 60 nm Au+ did not enhance the amplification efficiency of qPCR when the above primer was mutated. ConclusionsThe primers contain special palindrome sequences (GGATCC or ACCGGT) with 60 nm- Au+ can enhance the amplification efficiency of qPCR. Therefore, it suggests a more in-depth understanding of the mechanism and function of gold nanoparticles and primer sequences. This study has presented some implications for gold nanoparticles application in the development of qPCR technology.

Exercise of State Control over Local Self-Government in the Field of Environmental Protection

Today, environmental protection is a priority task for the governments of countries around the world due to the deepening of environmental problems and their impact on people's lives. Several problematic issues can and must be solved at the local level, which will make environmental policy more effective and take into account local needs. The study aimed to analyse the competence of local self-government bodies in terms of monitoring compliance with environmental legislation. A comparative analysis was used to study the issue of ensuring the protection of the environment and ecosystem by local self-government bodies through the prism of legal protection. During the research, several obstacles to the implementation of effective environmental protection measures at the local level were identified: the imperfection of the financing system, the lack of environmental awareness, the absence of effective administrative and procedural measures, and the imperfection of state control. In response to the identified problems, the positive experience of implementing the norms of the European Charter of Local Self-Government was investigated. It was established that the decentralization of local self-government had a positive effect on the protection of the ecosystem, as it brought local authorities closer to the public and provided local authorities with real powers to solve problems related to compliance with environmental legislation. In addition, to increase the effectiveness of mechanisms of state control over local self-government in the field of environmental protection, a system of principles of such control is proposed, consisting of publicity, systematicity, effectiveness, objectivity, impartiality, and universality. The proposed system will cover several key environmental problems and quickly and effectively solve them with the involvement of competent specialists and the public. The state of environmental protection at the local level is seen in further research and justification to determine practical recommendations for the implementation of decentralization of local self-government.