Chemical synthesis is essential in industries such as petrochemicals, fine chemicals, and pharmaceuticals, driving economic and social development. The increasing demand for new molecules and materials calls for novel...Chemical synthesis is essential in industries such as petrochemicals, fine chemicals, and pharmaceuticals, driving economic and social development. The increasing demand for new molecules and materials calls for novel chemical reactions;however, manual experimental screening is time-consuming. Artificial intelligence (AI) offers a promising solution by leveraging large-scale experimental data to model chemical reactions, although challenges such as the lack of standardization and predictability in chemical synthesis hinder AI applications. Additionally, the multi-scale nature of chemical reactions, along with complex multiphase processes, further complicates the task. Recent advances in microchemical systems, particularly continuous flow methods using microreactors, provide precise control over reaction conditions, enhancing reproducibility and enabling high-throughput experimentation. These systems minimize transport-related inconsistencies and facilitate scalable industrial applications. This review systematically explores recent developments in intelligent synthesis based on microchemical systems, focusing on reaction system design, synthesis robots, closed-loop optimization, and high-throughput experimentation, while identifying key areas for future research.展开更多
The contrast experiment of different stirring modes,which includes a new type of stirring-injection with the method of pulse and rotation,and the initial one-way stirring method,is done through physical simulation in ...The contrast experiment of different stirring modes,which includes a new type of stirring-injection with the method of pulse and rotation,and the initial one-way stirring method,is done through physical simulation in the laboratory.The stirring methods of pulse and rotation are of two kinds.One is pulsed and rotary stirrer with positive and opposite directions.The other is pulsed and rotary stirrer with rotation-stop-rotation.The results show that the stirring mode of pulse and rotation has better effects than the one-way stirring method.The specific effects are that the mixing time of the melting bath is apparently shortened,the number of grains involved in the liquid surface is increased,and the residence time of air bubble in water is doubled.展开更多
The natural world spent billions of years in solution-finding during evolution, which could benefit Technology. How do we put that in a nutshell? Biological systems are more complex than the most complex current techn...The natural world spent billions of years in solution-finding during evolution, which could benefit Technology. How do we put that in a nutshell? Biological systems are more complex than the most complex current technology. Any given function and effect are simultaneously coordinated and linked with others at many levels of biological organisation-from cell organelle to organism, to population and ecosystem. Technology does not have tools to deal with the complexity and “goal-intendedness” of living systems. But limits for interaction exist on both sides-Biological science itself is also too empirical and not mature enough to provide a solid base for correlating living with technical systems. Moving towards a synthesis, where engineers can utilize the vast amount of available biological data, we suggest using a tool called “Theory of Inventive Problem Solving” (TRIZ) and clarifying some important methodological issues, which have not previously been recognised in bionic engineering: 1) Requirement for more appropriate definitions of “system”, “effect”, “function”,“law” and “rule”. 2) Requirement for understanding or even measuring the degree of contradiction or analogy between functions in biological and artificial and/or non-living engineering system-there is no simple direct correlation between what engineers find useful and what biology does.展开更多
Gas fluidization has an ability to turn static particles to fluid-like dense flow, which allows greatly improved heat transfer among porous powders and highly efficient solid processing to become reality. As the risin...Gas fluidization has an ability to turn static particles to fluid-like dense flow, which allows greatly improved heat transfer among porous powders and highly efficient solid processing to become reality. As the rising star of current scientific research, some nanoparticles can also be fluidized in the form of agglomerates, with sizes ranging from tens to hundreds of microns. Herein, we have reviewed the recent progress on nanomaterial agglomeration and their fluidization behavior, the assisted techniques to enhance the fluidization of nanomaterials,including some mechanical measures, external fields and improved gas injections, as well as their effects on solid fluidization and mixing behaviors. Most of these techniques are effective in breaking large agglomerates and promoting particulate fluidization, meanwhile, the solid mixing is intensified under assisted fluidization. The applications of nanofluidization in nanostructured material production and sustainable chemical industry are further presented. In summary, the fluidization science of multidimensional, multicomponent and multifunctional particles, their multi-phase characterization, and the guideline of fluidized bed coupled process are prerequisites for the sustainable development of fluidized bed based materials, energy and chemical industry.展开更多
The range of coal-mine underground goaf has continuously expanded over time.Caving,fracture,and deformation zones have also changed,thereby inducing coal-mine water inrush and other environmental disasters.In this stu...The range of coal-mine underground goaf has continuously expanded over time.Caving,fracture,and deformation zones have also changed,thereby inducing coal-mine water inrush and other environmental disasters.In this study,4 D seismic monitoring technology that is effective in reservoir development was used to monitor abnormal changes in coal-mine underground goaf to explore the feasibility of the method.Taking a coal mine in Hancheng,Shaanxi as an example,we used the aforementioned technology to dynamically monitor the abnormal changes in the goaf.Based on the 4 D seismic data obtained in the experiment and the abnormal change characteristics of the coal-mine goaf,the method of 4 D seismic data processing in reservoir was improved.A set of 4 D data processing flow for the goaf was established,and the anomalies in the surface elevation and overlying strata velocity caused by collapse were corrected.We have made the following improvements to the method of 4 D seismic data processing in the reservoir:(1)the static correction problem caused by the changes of surface elevation and destruction of the low-velocity layer has been solved through fusion static correction to comb the low-frequency components of elevation statics with the high-frequency components of refraction statics;(2)the problem of overlying strata velocity changes in the goaf caused by collapse has been solved through the velocity consistency method;(3)the problem of reflection event pull-down in the disturbance area has been solved through space-varying moveout correction based on cross-correlation;and(4)amplitude anomalies in the coal seam caused by the goaf have been addressed using the correction method of space-varying amplitude.Results show that the 4 D seismic data processing and interpretation method established in this study is reasonable and effective.展开更多
All-solid-state lithium-sulfur batteries(ASSLSBs)employing sulfide solid electrolytes are one of the most promising next-generation energy storage systems due to their potential for higher energy density and safety.Ho...All-solid-state lithium-sulfur batteries(ASSLSBs)employing sulfide solid electrolytes are one of the most promising next-generation energy storage systems due to their potential for higher energy density and safety.However,scalable fabrication of sheet-type sulfur cathodes with high sulfur loading and excellent performances remains challenging.In this work,sheet-type freestanding sulfur cathodes with high sulfur loading were fabricated by dry electrode technology.The unique fibrous morphologies of polytetrafluoroethylene(PTFE)binders in dry electrodes not only provides excellent mechanical properties but also uncompromised ionic/electronic conductance.Even employed with thickened dry cathodes with high sulfur loading of 2 mg cm^(-2),ASSLSBs still exhibit outstanding rate performance and cycle stability.Moreover,the all-solid-state lithium-sulfur monolayer pouch cells(9.2 m Ah)were also demonstrated and exhibited excellent safety under a harsh test situation.This work verifies the potential of dry electrode technology in the scalable fabrication of thickened sulfur cathodes and will promote the practical applications of ASSLSBs.展开更多
The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are studied in...The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are studied in this research.The unconfined compression tests and one-dimensional oedometer swelling were performed after 7 d of curing to understand the influence of addition of 1%of RC material in the stabilised soils with the cement partially replaced by 49%,59%and 69%of ground granulated blast furnace slag(GBBS)or pulverised fuel ash(PFA).The moisture retention capacity of the stabilised clays was also explored using the soil-water retention curve(SWRC)from the measured suctions.Results confirmed an obvious effect of the use of RC with the obtained strength and swell properties of the stabilised clays suitable for road application at 50%replacement of cement.This outcome is associated with the in-depth and penetrating hydration of the cementitious materials by the RC and water which results in the production of needle-like matrix with interlocking filaments e a phenomenon referred to as the‘wrapping’effect.On the other hand,the SWRC used to describe the water holding capacity and corresponding swell mechanism of clays stabilised by a proportion of RC showed a satisfactory response.The moisture retention of the RC-modified clays was initially higher but reduced subsequently as the saturation level increased with decreasing suction.This phenomenon confirmed that clays stabilised by including the RC are water-proof in nature,thus ensuring reduced porosity and suction even at reduced water content.Overall,the stabilised clays with the combination of cement,GGBS and RC showed a better performance compared to those with the PFA included.展开更多
The precise managed pressure drilling(MPD)technology is mainly used to deal with the difficulties encountered when oil and gas open hole sections with multiple pressure systems and the strata with narrow safety densit...The precise managed pressure drilling(MPD)technology is mainly used to deal with the difficulties encountered when oil and gas open hole sections with multiple pressure systems and the strata with narrow safety density window are drilled through.If its liner cementing is carried out according to the conventional method,lost circulation is inevitable in the process of cementing while the displacement efficiency of smallclearance liner cementing is satisfied.If the positive and inverse injection technology is adopted,the cementing quality cannot meet the requirements of later well test engineering of ultradeep wells.In this paper,the cementing operation ofØ114.3 mm liner in Well Longgang 70 which was drilled in the Jiange structure of the Sichuan Basin was taken as an example to explore the application of the cementing technology based on the precise MPD and pressure balancing method to the cementing of long open-hole sections(as long as 859 m)with both high and low pressures running through multiple reservoirs.On the one hand,the technical measures were taken specifically to ensure the annulus filling efficiency of slurry and the pressure balance in the whole process of cementing.And on the other hand,the annulus pressure balance was precisely controlled by virtue of precise MPD devices and by injecting heavy weight drilling fluids through central pipes,and thus the wellbore pressure was kept steady in the whole process of cementing in the strata with narrow safety density window.It is indicated thatØ114.3 mm liner cementing in this well is good with qualified pressure tests and no channeling emerges at a funnel during the staged density reduction.It is concluded that this method can enhance the liner cementing quality of complex ultradeep gas wells and improve the wellbore conditions for the later safe well tests of high-pressure gas wells.展开更多
Based on an electrical resistance tomography(ERT) sensor and the data mining technology,a new voidage measurement method is proposed for air-water two-phase flow.The data mining technology used in this work is a least...Based on an electrical resistance tomography(ERT) sensor and the data mining technology,a new voidage measurement method is proposed for air-water two-phase flow.The data mining technology used in this work is a least squares support vector machine(LS-SVM) algorithm together with the feature extraction method,and three feature extraction methods are tested:principal component analysis(PCA),partial least squares(PLS) and independent component analysis(ICA).In the practical voidage measurement process,the flow pattern is firstly identified directly from the conductance values obtained by the ERT sensor.Then,the appropriate voidage measurement model is selected according to the flow pattern identification result.Finally,the voidage is calculated.Experimental results show that the proposed method can measure the voidage effectively,and the measurement accuracy and speed are satisfactory.Compared with the conventional voidage measurement methods based on ERT,the proposed method doesn't need any image reconstruction process,so it has the advantage of good real-time performance.Due to the introduction of flow pattern identification,the influence of flow pattern on the voidage measurement is overcome.Besides,it is demonstrated that the LS-SVM method with PLS feature extraction presents the best measurement performance among the tested methods.展开更多
It is a common observation that whenever patients arrives at the front desk of a hospital,outpatient clinic,or other health-associated centers,they have to first queue up in a line and wait to fill in their registrati...It is a common observation that whenever patients arrives at the front desk of a hospital,outpatient clinic,or other health-associated centers,they have to first queue up in a line and wait to fill in their registration form to get admitted.The long waiting time without any status updates is the most common complaint,concerning health officials.In this paper,UrNext,a location-aware mobile-based solution using Bluetooth low-energy(BLE)technology is presented to solve the problem.Recently,a technology-oriented method,the Internet of Things(IoT),has been gaining popularity in helping to solve some of the healthcare sector’s problems.The implementation of this solution could be illustrated through a simple example of when a patient arrives at a clinic for a consultation.Instead of having to wait in long lines,that patient will be greeted automatically,receive a push notification of an admittance along with an estimated waiting time for a consultation session.This will not only provide the patients with a sense of freedom but would also reduce the uncertainty levels that are generally observed,thus saving both time and money.This work aims to improve the clinics’quality of services,organize queues and minimize waiting times,leading to patients’comfort while reducing the burden on nurses and receptionists.The results demonstrate that the presented system is successful in its performance and helps achieves a plea-sant and conducive clinic visitation process with higher productivity.展开更多
This paper presents an integration methodology for ma chining and measuring processes using OMM (On-Machine Measurement) technology b ased on CAD/CAM/CAI integration concept. OMM uses a CNC machining center as a me as...This paper presents an integration methodology for ma chining and measuring processes using OMM (On-Machine Measurement) technology b ased on CAD/CAM/CAI integration concept. OMM uses a CNC machining center as a me asuring station by changing the tools into measuring probes such as touch-type, laser and vision. Although the measurement accuracy is not good compared to tha t of the CMM (Coordinate Measuring Machine), there are distinctive advantages us ing OMM in real situation. In this paper, two topics are handled to show the eff ectiveness of the machining and measuring process integration: (1) inspection pl anning strategy for sculptured surface machining and (2) tool path compensation for profile milling process. For the first topic, as a first step, effective mea suring point locations are determined to obtain optimum results for given sampli ng numbers. Two measuring point selection methods are suggested based on the CAD /CAM/CAI integration concept: (1) by the prediction of cutting errors and (2) by considering cutter contact points to avoid the measurement errors caused by cus ps. As a next step, the TSP (Traveling Salesman Problem) algorithm is applied to minimize the probe moving distance. Appropriate simulations and experiments are performed to verify the proposed inspection planning strategy, and the results are analyzed. For the second topic, a methodology for profile milling error comp ensation is presented by using an ANN (Artificial Neural Network) model trained by the inspection database of OMM system. First, geometric and thermal errors of the machining center are compensated using a closed-loop configuration for the improvement of machining and inspection accuracy. The probing errors are also t aken into account. Then, a specimen workpiece is machined and then the machi ning surface error distribution is measured on the machine using touch-type pro be. In order to efficiently analyze the machining errors, two characteristic err or parameters (W err and D err) are defined. Subsequently, these param eters are modeled by applying the RFB (Radial Basis Function) network approach a s an ANN model. Based on the RBF network model, the tool paths are compensated i n order to effectively reduce the errors by employing an iterative algorithm. In order to validate the approaches proposed in this paper, a concrete case of the machining process is taken into account and about 90% of machining error reduction is successfully accomplished through the proposed approaches.展开更多
The advancement of the fourth industrial revolution has shaped the integration and interaction of different information, communication and technologies (ICTs) in the merging cyber, physical, and social infrastructures...The advancement of the fourth industrial revolution has shaped the integration and interaction of different information, communication and technologies (ICTs) in the merging cyber, physical, and social infrastructures. The impact of ICT has accelerated the progress of the United Nation’s Sustainable Development Goals (UN SDGs) and influenced the evolution of smart, sustainable, stable society development. Making the trustworthy information and communication technologies infrastructure widely available will promote the community innovation needed to stimulate domestic economics, provide decent work, and reduce inequalities. This article attempts to outline a big picture about the International Telecommunication Union (ITU)’s trust provisioning framework, including its motivation, current status, and application for achieving the UN SDGs by 2030. This article first describes the purpose of the UN SDGs and the evolution of the industrial revolution, then demonstrates the challenges of global risks affecting the fourth industrial revolution and the need for trustworthy ICT infrastructures. Subsequently, the article evaluates the ITU trust provisioning framework and assesses its applications in the future knowledge society, trust provisioning ecosystem, and cyber, physical, and social infrastructure toward achieving UN SDGs. Use cases are also presented in this article to show the effectiveness of the ITU trust provisioning framework on achieving UN SDGs.展开更多
Modeling and investigation of HF electromagnetic heating in induction devices with unclosed magnetic circuit has allowed to optimize heating speed in local zones of formation of soldering connections and to improve th...Modeling and investigation of HF electromagnetic heating in induction devices with unclosed magnetic circuit has allowed to optimize heating speed in local zones of formation of soldering connections and to improve their quality due to joint action of superficial effects and electromagnetic forces.For all magnetic materials is nonlinear decrease in heating power depending on frequency of HF.Installed the optimal parameters of HF heating for soldering electronics modules by inductor with open-ended magnetic conductor.展开更多
According to the basic problem of industrial production, the paper presents a monocular camera and automatic annotation ranging scheme with a ruler. The scheme eliminates a series of complex operation steps frequently...According to the basic problem of industrial production, the paper presents a monocular camera and automatic annotation ranging scheme with a ruler. The scheme eliminates a series of complex operation steps frequently used for image location of the calibration, image correction, it has simple implementation and has successfully realized precise ranging by using digital image processing technology. From the beginning of the analysis of image edge detection, edge detection principle and some common edge detection operators, and proposes an improved multi-scale edge detection algorithm, then according to the particularity of the edge proposed new edge thinning algorithm, finally mark the target point through the feature extraction, calculate the final results of fault location.展开更多
Diabetes mellitus(DM),an increasingly prevalent chronic metabolic disease,is characterised by prolonged hyperglycaemia,which leads to long-term health consequences.Although much effort has been put into understanding ...Diabetes mellitus(DM),an increasingly prevalent chronic metabolic disease,is characterised by prolonged hyperglycaemia,which leads to long-term health consequences.Although much effort has been put into understanding the pathogenesis of diabetic wounds,the underlying mechanisms remain unclear.The advent of single-cell RNA sequencing(scRNAseq)has revolutionised biological research by enabling the identification of novel cell types,the discovery of cellular markers,the analysis of gene expression patterns and the prediction of develop-mental trajectories.This powerful tool allows for an in-depth exploration of pathogenesis at the cellular and molecular levels.In this editorial,we focus on progenitor-based repair strategies for diabetic wound healing as revealed by scRNAseq and highlight the biological behaviour of various healing-related cells and the alteration of signalling pathways in the process of diabetic wound healing.ScRNAseq could not only deepen our understanding of the complex biology of diabetic wounds but also identify and validate new targets for inter-vention,offering hope for improved patient outcomes in the management of this challenging complication of DM.展开更多
＂Without an appropriate research setting, a study cannot be qualified as a reasonable piece＂, this notion is manifested in the methodological polices. In this research, we attempt to examine previous studies within ...＂Without an appropriate research setting, a study cannot be qualified as a reasonable piece＂, this notion is manifested in the methodological polices. In this research, we attempt to examine previous studies within the scope of technology evolution and market perception in telecommunication industry through extracting research structures, methodologies, corresponding variables, and processing methods. A general process of social scientific research is adopted to analyze eighty-four selected papers; and simultaneously, the framework for doing this analysis is established, as well. In this manner, we inspect the subjects and the issues in these papers according to product types, academic domains, and divisions of technological evolution （from 1G to 4G）. Then, their research designs are anatomized into the key dimensions of general research conventions. This research eventually provides an entire picture of a research scenario for mobile telecommunication industry; and apparently, this framewbrk can help scholars to establish specific tendencies for academic scenarios in future research plans. Also, we propose the main streams and emerging issues can be expected to engage in the future within both theacademic and the operational fields.展开更多
Speech recognition systems have become a unique human-computer interaction(HCI)family.Speech is one of the most naturally developed human abilities;speech signal processing opens up a transparent and hand-free computa...Speech recognition systems have become a unique human-computer interaction(HCI)family.Speech is one of the most naturally developed human abilities;speech signal processing opens up a transparent and hand-free computation experience.This paper aims to present a retrospective yet modern approach to the world of speech recognition systems.The development journey of ASR(Automatic Speech Recognition)has seen quite a few milestones and breakthrough technologies that have been highlighted in this paper.A step-by-step rundown of the fundamental stages in developing speech recognition systems has been presented,along with a brief discussion of various modern-day developments and applications in this domain.This review paper aims to summarize and provide a beginning point for those starting in the vast field of speech signal processing.Since speech recognition has a vast potential in various industries like telecommunication,emotion recognition,healthcare,etc.,this review would be helpful to researchers who aim at exploring more applications that society can quickly adopt in future years of evolution.展开更多
Background: The hospitals and health care centres are organized around the patient, a model in which healthcare providers partner with patients and families to identify and satisfy patients’ needs and preferences. Pr...Background: The hospitals and health care centres are organized around the patient, a model in which healthcare providers partner with patients and families to identify and satisfy patients’ needs and preferences. Providers respect patients’ values and preferences, address their emotional and social needs, and involve them and their families in decision making. According to the best of our knowledge, there is no evidence to prove, radiologists and radiographers are aware enough about the patient safety, care, and code of conduct with their patients in the interventional radiology department. Objective: This article aims to measure the awareness of radiologists and radiographers toward care and safety in an interventional radiology department. Material and Method: This study was carried in period from 15 February to 20 April 2022. One hundred sixty-four radiographers and radiologists participating in this study completed the questionnaire, which equals a response rate of approximately 82%. The questionnaire was fully completed by almost all responders;only a few of them gave partial answers. Results: The first question for radiographers and radiologists was “the sufficient awareness about the patient safety and care during the interventional radiology procedure. Also, the majority of the radiographers and radiologists are providing the patients with sufficient information when he/she ask for help or queries. A large number of radiographers and radiologists were participating in this study explaining the procedures to patients before starting the examinations in a structured way. Finally, the result shows both radiographers and radiologists respect the patient’s rights, privacy, and dignity and also kept the radiation protection during the interventional radiology procedures. Conclusion: This article summarizes the key categories of awareness of patient care issues in the provision of interventional radiology services, from the joint perspectives of radiographers and radiologists, and provides references for further reading in all major relevant areas.展开更多
The generation of terahertz(THz) waves by focusing a femtosecond pulsed laser beam at a distance is able to overcome the strong absorption properties of air and has rapidly attracted the attention of industry. However...The generation of terahertz(THz) waves by focusing a femtosecond pulsed laser beam at a distance is able to overcome the strong absorption properties of air and has rapidly attracted the attention of industry. However, the poor directionality of the THz wave radiation generated by this method is not conducive to THz wave applications. By controlling the morphology of the ultrafast laser-excited plasma filament and its electron density distribution through coherent beam combining technology, we achieve direct THz beam shaping and are able to obtain THz wave radiation of Gaussian or arbitrary transverse distribution. The novel experimental approach proposed in this paper opens up the research field of direct THz wave shaping using plasma. Moreover, it innovates multi-parameter convergence algorithms and, by doing so, has the potential to find beam patterns with higher energy conversion efficiency and break the energy limit of THz waves emitted by lasers at high power.展开更多
基金supported by the National Natural Science Foundation of China(22378227)Shijiazhuang Science and Technology Bureau(231790163A).
文摘Chemical synthesis is essential in industries such as petrochemicals, fine chemicals, and pharmaceuticals, driving economic and social development. The increasing demand for new molecules and materials calls for novel chemical reactions;however, manual experimental screening is time-consuming. Artificial intelligence (AI) offers a promising solution by leveraging large-scale experimental data to model chemical reactions, although challenges such as the lack of standardization and predictability in chemical synthesis hinder AI applications. Additionally, the multi-scale nature of chemical reactions, along with complex multiphase processes, further complicates the task. Recent advances in microchemical systems, particularly continuous flow methods using microreactors, provide precise control over reaction conditions, enhancing reproducibility and enabling high-throughput experimentation. These systems minimize transport-related inconsistencies and facilitate scalable industrial applications. This review systematically explores recent developments in intelligent synthesis based on microchemical systems, focusing on reaction system design, synthesis robots, closed-loop optimization, and high-throughput experimentation, while identifying key areas for future research.
文摘The contrast experiment of different stirring modes,which includes a new type of stirring-injection with the method of pulse and rotation,and the initial one-way stirring method,is done through physical simulation in the laboratory.The stirring methods of pulse and rotation are of two kinds.One is pulsed and rotary stirrer with positive and opposite directions.The other is pulsed and rotary stirrer with rotation-stop-rotation.The results show that the stirring mode of pulse and rotation has better effects than the one-way stirring method.The specific effects are that the mixing time of the melting bath is apparently shortened,the number of grains involved in the liquid surface is increased,and the residence time of air bubble in water is doubled.
文摘The natural world spent billions of years in solution-finding during evolution, which could benefit Technology. How do we put that in a nutshell? Biological systems are more complex than the most complex current technology. Any given function and effect are simultaneously coordinated and linked with others at many levels of biological organisation-from cell organelle to organism, to population and ecosystem. Technology does not have tools to deal with the complexity and “goal-intendedness” of living systems. But limits for interaction exist on both sides-Biological science itself is also too empirical and not mature enough to provide a solid base for correlating living with technical systems. Moving towards a synthesis, where engineers can utilize the vast amount of available biological data, we suggest using a tool called “Theory of Inventive Problem Solving” (TRIZ) and clarifying some important methodological issues, which have not previously been recognised in bionic engineering: 1) Requirement for more appropriate definitions of “system”, “effect”, “function”,“law” and “rule”. 2) Requirement for understanding or even measuring the degree of contradiction or analogy between functions in biological and artificial and/or non-living engineering system-there is no simple direct correlation between what engineers find useful and what biology does.
基金Supported by the National Natural Science Foundation of China(21306102 and21422604)China Postdoctoral Science Foundation(2015M571049)
文摘Gas fluidization has an ability to turn static particles to fluid-like dense flow, which allows greatly improved heat transfer among porous powders and highly efficient solid processing to become reality. As the rising star of current scientific research, some nanoparticles can also be fluidized in the form of agglomerates, with sizes ranging from tens to hundreds of microns. Herein, we have reviewed the recent progress on nanomaterial agglomeration and their fluidization behavior, the assisted techniques to enhance the fluidization of nanomaterials,including some mechanical measures, external fields and improved gas injections, as well as their effects on solid fluidization and mixing behaviors. Most of these techniques are effective in breaking large agglomerates and promoting particulate fluidization, meanwhile, the solid mixing is intensified under assisted fluidization. The applications of nanofluidization in nanostructured material production and sustainable chemical industry are further presented. In summary, the fluidization science of multidimensional, multicomponent and multifunctional particles, their multi-phase characterization, and the guideline of fluidized bed coupled process are prerequisites for the sustainable development of fluidized bed based materials, energy and chemical industry.
基金funded by the National Key Research and Development Program Subject(No.2018YFC0807804)。
文摘The range of coal-mine underground goaf has continuously expanded over time.Caving,fracture,and deformation zones have also changed,thereby inducing coal-mine water inrush and other environmental disasters.In this study,4 D seismic monitoring technology that is effective in reservoir development was used to monitor abnormal changes in coal-mine underground goaf to explore the feasibility of the method.Taking a coal mine in Hancheng,Shaanxi as an example,we used the aforementioned technology to dynamically monitor the abnormal changes in the goaf.Based on the 4 D seismic data obtained in the experiment and the abnormal change characteristics of the coal-mine goaf,the method of 4 D seismic data processing in reservoir was improved.A set of 4 D data processing flow for the goaf was established,and the anomalies in the surface elevation and overlying strata velocity caused by collapse were corrected.We have made the following improvements to the method of 4 D seismic data processing in the reservoir:(1)the static correction problem caused by the changes of surface elevation and destruction of the low-velocity layer has been solved through fusion static correction to comb the low-frequency components of elevation statics with the high-frequency components of refraction statics;(2)the problem of overlying strata velocity changes in the goaf caused by collapse has been solved through the velocity consistency method;(3)the problem of reflection event pull-down in the disturbance area has been solved through space-varying moveout correction based on cross-correlation;and(4)amplitude anomalies in the coal seam caused by the goaf have been addressed using the correction method of space-varying amplitude.Results show that the 4 D seismic data processing and interpretation method established in this study is reasonable and effective.
基金supported by the National Key Research and Development Program of China(2021YFB2500300)the National Natural Science Foundation of China(22075029,22108151,22109084)the China Postdoctoral Science Foundation(2021TQ0164)。
文摘All-solid-state lithium-sulfur batteries(ASSLSBs)employing sulfide solid electrolytes are one of the most promising next-generation energy storage systems due to their potential for higher energy density and safety.However,scalable fabrication of sheet-type sulfur cathodes with high sulfur loading and excellent performances remains challenging.In this work,sheet-type freestanding sulfur cathodes with high sulfur loading were fabricated by dry electrode technology.The unique fibrous morphologies of polytetrafluoroethylene(PTFE)binders in dry electrodes not only provides excellent mechanical properties but also uncompromised ionic/electronic conductance.Even employed with thickened dry cathodes with high sulfur loading of 2 mg cm^(-2),ASSLSBs still exhibit outstanding rate performance and cycle stability.Moreover,the all-solid-state lithium-sulfur monolayer pouch cells(9.2 m Ah)were also demonstrated and exhibited excellent safety under a harsh test situation.This work verifies the potential of dry electrode technology in the scalable fabrication of thickened sulfur cathodes and will promote the practical applications of ASSLSBs.
文摘The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are studied in this research.The unconfined compression tests and one-dimensional oedometer swelling were performed after 7 d of curing to understand the influence of addition of 1%of RC material in the stabilised soils with the cement partially replaced by 49%,59%and 69%of ground granulated blast furnace slag(GBBS)or pulverised fuel ash(PFA).The moisture retention capacity of the stabilised clays was also explored using the soil-water retention curve(SWRC)from the measured suctions.Results confirmed an obvious effect of the use of RC with the obtained strength and swell properties of the stabilised clays suitable for road application at 50%replacement of cement.This outcome is associated with the in-depth and penetrating hydration of the cementitious materials by the RC and water which results in the production of needle-like matrix with interlocking filaments e a phenomenon referred to as the‘wrapping’effect.On the other hand,the SWRC used to describe the water holding capacity and corresponding swell mechanism of clays stabilised by a proportion of RC showed a satisfactory response.The moisture retention of the RC-modified clays was initially higher but reduced subsequently as the saturation level increased with decreasing suction.This phenomenon confirmed that clays stabilised by including the RC are water-proof in nature,thus ensuring reduced porosity and suction even at reduced water content.Overall,the stabilised clays with the combination of cement,GGBS and RC showed a better performance compared to those with the PFA included.
文摘The precise managed pressure drilling(MPD)technology is mainly used to deal with the difficulties encountered when oil and gas open hole sections with multiple pressure systems and the strata with narrow safety density window are drilled through.If its liner cementing is carried out according to the conventional method,lost circulation is inevitable in the process of cementing while the displacement efficiency of smallclearance liner cementing is satisfied.If the positive and inverse injection technology is adopted,the cementing quality cannot meet the requirements of later well test engineering of ultradeep wells.In this paper,the cementing operation ofØ114.3 mm liner in Well Longgang 70 which was drilled in the Jiange structure of the Sichuan Basin was taken as an example to explore the application of the cementing technology based on the precise MPD and pressure balancing method to the cementing of long open-hole sections(as long as 859 m)with both high and low pressures running through multiple reservoirs.On the one hand,the technical measures were taken specifically to ensure the annulus filling efficiency of slurry and the pressure balance in the whole process of cementing.And on the other hand,the annulus pressure balance was precisely controlled by virtue of precise MPD devices and by injecting heavy weight drilling fluids through central pipes,and thus the wellbore pressure was kept steady in the whole process of cementing in the strata with narrow safety density window.It is indicated thatØ114.3 mm liner cementing in this well is good with qualified pressure tests and no channeling emerges at a funnel during the staged density reduction.It is concluded that this method can enhance the liner cementing quality of complex ultradeep gas wells and improve the wellbore conditions for the later safe well tests of high-pressure gas wells.
基金Supported by the National Natural Science Foundation of China (60972138)
文摘Based on an electrical resistance tomography(ERT) sensor and the data mining technology,a new voidage measurement method is proposed for air-water two-phase flow.The data mining technology used in this work is a least squares support vector machine(LS-SVM) algorithm together with the feature extraction method,and three feature extraction methods are tested:principal component analysis(PCA),partial least squares(PLS) and independent component analysis(ICA).In the practical voidage measurement process,the flow pattern is firstly identified directly from the conductance values obtained by the ERT sensor.Then,the appropriate voidage measurement model is selected according to the flow pattern identification result.Finally,the voidage is calculated.Experimental results show that the proposed method can measure the voidage effectively,and the measurement accuracy and speed are satisfactory.Compared with the conventional voidage measurement methods based on ERT,the proposed method doesn't need any image reconstruction process,so it has the advantage of good real-time performance.Due to the introduction of flow pattern identification,the influence of flow pattern on the voidage measurement is overcome.Besides,it is demonstrated that the LS-SVM method with PLS feature extraction presents the best measurement performance among the tested methods.
基金The author extends her appreciation to the Deanship of Scientific Research at King Saud University for funding this work through the Undergraduate Research Support Program,Project no.(URSP-3-18-89).
文摘It is a common observation that whenever patients arrives at the front desk of a hospital,outpatient clinic,or other health-associated centers,they have to first queue up in a line and wait to fill in their registration form to get admitted.The long waiting time without any status updates is the most common complaint,concerning health officials.In this paper,UrNext,a location-aware mobile-based solution using Bluetooth low-energy(BLE)technology is presented to solve the problem.Recently,a technology-oriented method,the Internet of Things(IoT),has been gaining popularity in helping to solve some of the healthcare sector’s problems.The implementation of this solution could be illustrated through a simple example of when a patient arrives at a clinic for a consultation.Instead of having to wait in long lines,that patient will be greeted automatically,receive a push notification of an admittance along with an estimated waiting time for a consultation session.This will not only provide the patients with a sense of freedom but would also reduce the uncertainty levels that are generally observed,thus saving both time and money.This work aims to improve the clinics’quality of services,organize queues and minimize waiting times,leading to patients’comfort while reducing the burden on nurses and receptionists.The results demonstrate that the presented system is successful in its performance and helps achieves a plea-sant and conducive clinic visitation process with higher productivity.
文摘This paper presents an integration methodology for ma chining and measuring processes using OMM (On-Machine Measurement) technology b ased on CAD/CAM/CAI integration concept. OMM uses a CNC machining center as a me asuring station by changing the tools into measuring probes such as touch-type, laser and vision. Although the measurement accuracy is not good compared to tha t of the CMM (Coordinate Measuring Machine), there are distinctive advantages us ing OMM in real situation. In this paper, two topics are handled to show the eff ectiveness of the machining and measuring process integration: (1) inspection pl anning strategy for sculptured surface machining and (2) tool path compensation for profile milling process. For the first topic, as a first step, effective mea suring point locations are determined to obtain optimum results for given sampli ng numbers. Two measuring point selection methods are suggested based on the CAD /CAM/CAI integration concept: (1) by the prediction of cutting errors and (2) by considering cutter contact points to avoid the measurement errors caused by cus ps. As a next step, the TSP (Traveling Salesman Problem) algorithm is applied to minimize the probe moving distance. Appropriate simulations and experiments are performed to verify the proposed inspection planning strategy, and the results are analyzed. For the second topic, a methodology for profile milling error comp ensation is presented by using an ANN (Artificial Neural Network) model trained by the inspection database of OMM system. First, geometric and thermal errors of the machining center are compensated using a closed-loop configuration for the improvement of machining and inspection accuracy. The probing errors are also t aken into account. Then, a specimen workpiece is machined and then the machi ning surface error distribution is measured on the machine using touch-type pro be. In order to efficiently analyze the machining errors, two characteristic err or parameters (W err and D err) are defined. Subsequently, these param eters are modeled by applying the RFB (Radial Basis Function) network approach a s an ANN model. Based on the RBF network model, the tool paths are compensated i n order to effectively reduce the errors by employing an iterative algorithm. In order to validate the approaches proposed in this paper, a concrete case of the machining process is taken into account and about 90% of machining error reduction is successfully accomplished through the proposed approaches.
文摘The advancement of the fourth industrial revolution has shaped the integration and interaction of different information, communication and technologies (ICTs) in the merging cyber, physical, and social infrastructures. The impact of ICT has accelerated the progress of the United Nation’s Sustainable Development Goals (UN SDGs) and influenced the evolution of smart, sustainable, stable society development. Making the trustworthy information and communication technologies infrastructure widely available will promote the community innovation needed to stimulate domestic economics, provide decent work, and reduce inequalities. This article attempts to outline a big picture about the International Telecommunication Union (ITU)’s trust provisioning framework, including its motivation, current status, and application for achieving the UN SDGs by 2030. This article first describes the purpose of the UN SDGs and the evolution of the industrial revolution, then demonstrates the challenges of global risks affecting the fourth industrial revolution and the need for trustworthy ICT infrastructures. Subsequently, the article evaluates the ITU trust provisioning framework and assesses its applications in the future knowledge society, trust provisioning ecosystem, and cyber, physical, and social infrastructure toward achieving UN SDGs. Use cases are also presented in this article to show the effectiveness of the ITU trust provisioning framework on achieving UN SDGs.
文摘Modeling and investigation of HF electromagnetic heating in induction devices with unclosed magnetic circuit has allowed to optimize heating speed in local zones of formation of soldering connections and to improve their quality due to joint action of superficial effects and electromagnetic forces.For all magnetic materials is nonlinear decrease in heating power depending on frequency of HF.Installed the optimal parameters of HF heating for soldering electronics modules by inductor with open-ended magnetic conductor.
文摘According to the basic problem of industrial production, the paper presents a monocular camera and automatic annotation ranging scheme with a ruler. The scheme eliminates a series of complex operation steps frequently used for image location of the calibration, image correction, it has simple implementation and has successfully realized precise ranging by using digital image processing technology. From the beginning of the analysis of image edge detection, edge detection principle and some common edge detection operators, and proposes an improved multi-scale edge detection algorithm, then according to the particularity of the edge proposed new edge thinning algorithm, finally mark the target point through the feature extraction, calculate the final results of fault location.
基金Supported by Shenzhen Science and Technology Program,No.GJHZ20210705142543019Guangdong Basic and Applied Basic Research Foundation,No.2023A1515220074.
文摘Diabetes mellitus(DM),an increasingly prevalent chronic metabolic disease,is characterised by prolonged hyperglycaemia,which leads to long-term health consequences.Although much effort has been put into understanding the pathogenesis of diabetic wounds,the underlying mechanisms remain unclear.The advent of single-cell RNA sequencing(scRNAseq)has revolutionised biological research by enabling the identification of novel cell types,the discovery of cellular markers,the analysis of gene expression patterns and the prediction of develop-mental trajectories.This powerful tool allows for an in-depth exploration of pathogenesis at the cellular and molecular levels.In this editorial,we focus on progenitor-based repair strategies for diabetic wound healing as revealed by scRNAseq and highlight the biological behaviour of various healing-related cells and the alteration of signalling pathways in the process of diabetic wound healing.ScRNAseq could not only deepen our understanding of the complex biology of diabetic wounds but also identify and validate new targets for inter-vention,offering hope for improved patient outcomes in the management of this challenging complication of DM.
文摘＂Without an appropriate research setting, a study cannot be qualified as a reasonable piece＂, this notion is manifested in the methodological polices. In this research, we attempt to examine previous studies within the scope of technology evolution and market perception in telecommunication industry through extracting research structures, methodologies, corresponding variables, and processing methods. A general process of social scientific research is adopted to analyze eighty-four selected papers; and simultaneously, the framework for doing this analysis is established, as well. In this manner, we inspect the subjects and the issues in these papers according to product types, academic domains, and divisions of technological evolution （from 1G to 4G）. Then, their research designs are anatomized into the key dimensions of general research conventions. This research eventually provides an entire picture of a research scenario for mobile telecommunication industry; and apparently, this framewbrk can help scholars to establish specific tendencies for academic scenarios in future research plans. Also, we propose the main streams and emerging issues can be expected to engage in the future within both theacademic and the operational fields.
文摘Speech recognition systems have become a unique human-computer interaction(HCI)family.Speech is one of the most naturally developed human abilities;speech signal processing opens up a transparent and hand-free computation experience.This paper aims to present a retrospective yet modern approach to the world of speech recognition systems.The development journey of ASR(Automatic Speech Recognition)has seen quite a few milestones and breakthrough technologies that have been highlighted in this paper.A step-by-step rundown of the fundamental stages in developing speech recognition systems has been presented,along with a brief discussion of various modern-day developments and applications in this domain.This review paper aims to summarize and provide a beginning point for those starting in the vast field of speech signal processing.Since speech recognition has a vast potential in various industries like telecommunication,emotion recognition,healthcare,etc.,this review would be helpful to researchers who aim at exploring more applications that society can quickly adopt in future years of evolution.
文摘Background: The hospitals and health care centres are organized around the patient, a model in which healthcare providers partner with patients and families to identify and satisfy patients’ needs and preferences. Providers respect patients’ values and preferences, address their emotional and social needs, and involve them and their families in decision making. According to the best of our knowledge, there is no evidence to prove, radiologists and radiographers are aware enough about the patient safety, care, and code of conduct with their patients in the interventional radiology department. Objective: This article aims to measure the awareness of radiologists and radiographers toward care and safety in an interventional radiology department. Material and Method: This study was carried in period from 15 February to 20 April 2022. One hundred sixty-four radiographers and radiologists participating in this study completed the questionnaire, which equals a response rate of approximately 82%. The questionnaire was fully completed by almost all responders;only a few of them gave partial answers. Results: The first question for radiographers and radiologists was “the sufficient awareness about the patient safety and care during the interventional radiology procedure. Also, the majority of the radiographers and radiologists are providing the patients with sufficient information when he/she ask for help or queries. A large number of radiographers and radiologists were participating in this study explaining the procedures to patients before starting the examinations in a structured way. Finally, the result shows both radiographers and radiologists respect the patient’s rights, privacy, and dignity and also kept the radiation protection during the interventional radiology procedures. Conclusion: This article summarizes the key categories of awareness of patient care issues in the provision of interventional radiology services, from the joint perspectives of radiographers and radiologists, and provides references for further reading in all major relevant areas.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 12074272 and 61905271)the National Defense Science and Technology Innovation Special Zone Project of China (Grant No. 20-163-02-ZT-008-009-01)Guangdong Basic and Applied Basic Research Foundation (Grant No. 2020A1515011083)。
文摘The generation of terahertz(THz) waves by focusing a femtosecond pulsed laser beam at a distance is able to overcome the strong absorption properties of air and has rapidly attracted the attention of industry. However, the poor directionality of the THz wave radiation generated by this method is not conducive to THz wave applications. By controlling the morphology of the ultrafast laser-excited plasma filament and its electron density distribution through coherent beam combining technology, we achieve direct THz beam shaping and are able to obtain THz wave radiation of Gaussian or arbitrary transverse distribution. The novel experimental approach proposed in this paper opens up the research field of direct THz wave shaping using plasma. Moreover, it innovates multi-parameter convergence algorithms and, by doing so, has the potential to find beam patterns with higher energy conversion efficiency and break the energy limit of THz waves emitted by lasers at high power.
