The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the ...The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the uncertainties in train driving and operation,this paper analyzes the relationship between the safety of heavy-haul electric locomotive hauled trains and driving and operation.It studies the auxiliary intelligent driving safety operation control methods.Through K-means to identify the characteristics of drivers'driving manipulation,the hidden Markov model adaptively adjusts the train driving and operation sequence,and conducts auxiliary driving reconstruction for heavy-haul locomotive driving and operation.Based on the train running curve and the locomotive traction/braking characteristics,it smoothly controls the exertion of the traction/braking force of heavy-haul locomotives,thereby optimizing the driving safety control of heavy-haul trains in the vehicle-environment-track system.Finally,the train operation simulation and optimized driving verification are carried out by simulating some track sections.The results show that the proposed method can correct and pre-optimize driving operations,improving the smoothness of heavy-haul trains by approximately 10%.It verifies the effectiveness of the proposed train assisted driving control reconstruction method,facilitating the smooth and safe operation of heavy-haul trains.展开更多
Considering the impact of electromagnetic induction on neurons,this paper presents a three-dimensional(3D)memristor Hindmarsh–Rose(HR)neuron model.This model exhibits diverse hidden chaotic dynamics due to the absenc...Considering the impact of electromagnetic induction on neurons,this paper presents a three-dimensional(3D)memristor Hindmarsh–Rose(HR)neuron model.This model exhibits diverse hidden chaotic dynamics due to the absence of equilibrium points,including bifurcation phenomena,coexisting attractors,transient chaos,state transitions,and offsetboosting control.Since equilibrium points are absent in this model,all observed dynamics are classified as hidden behaviors.The complex dynamics of this neuron model are illustrated through bifurcation diagrams,Lyapunov diagrams,time series plots,and phase portraits.Furthermore,an equivalent circuit for the memristor HR neuron is constructed,and the accuracy of numerical simulations is confirmed via circuit simulation results.展开更多
One method to change the bifurcation characteristics of chaotic systems is anti-control,which can either delay or advance bifur-cation and transform an unstable state into a stable one.The chaotic system with infinite...One method to change the bifurcation characteristics of chaotic systems is anti-control,which can either delay or advance bifur-cation and transform an unstable state into a stable one.The chaotic system with infinite equilibria exhibits complex bifurcation characteris-tics.The Hopf bifurcation and hidden attractors with symmetric coexistence of the system are analyzed.An improved dynamic state feed-back control method is adopted to reduce the tedious calculation process to prevent the Hopf bifurcation from being controlled.A hybrid controller that includes both nonlinear and linear controllers is set up for the system.With the method,the delay and stability of the Hopf bifurcation of the system are studied and the goal of anti-control is achieved.Numerical analysis verified the correctness.展开更多
The Internet of Things (IoT) and edge-assisted networking infrastructures are capable of bringing data processing and accessibility services locally at the respective edge rather than at a centralized module. These in...The Internet of Things (IoT) and edge-assisted networking infrastructures are capable of bringing data processing and accessibility services locally at the respective edge rather than at a centralized module. These infrastructures are very effective in providing a fast response to the respective queries of the requesting modules, but their distributed nature has introduced other problems such as security and privacy. To address these problems, various security-assisted communication mechanisms have been developed to safeguard every active module, i.e., devices and edges, from every possible vulnerability in the IoT. However, these methodologies have neglected one of the critical issues, which is the prediction of fraudulent devices, i.e., adversaries, preferably as early as possible in the IoT. In this paper, a hybrid communication mechanism is presented where the Hidden Markov Model (HMM) predicts the legitimacy of the requesting device (both source and destination), and the Advanced Encryption Standard (AES) safeguards the reliability of the transmitted data over a shared communication medium, preferably through a secret shared key, i.e., , and timestamp information. A device becomes trusted if it has passed both evaluation levels, i.e., HMM and message decryption, within a stipulated time interval. The proposed hybrid, along with existing state-of-the-art approaches, has been simulated in the realistic environment of the IoT to verify the security measures. These evaluations were carried out in the presence of intruders capable of launching various attacks simultaneously, such as man-in-the-middle, device impersonations, and masquerading attacks. Moreover, the proposed approach has been proven to be more effective than existing state-of-the-art approaches due to its exceptional performance in communication, processing, and storage overheads, i.e., 13%, 19%, and 16%, respectively. Finally, the proposed hybrid approach is pruned against well-known security attacks in the IoT.展开更多
With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the...With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the critical issues.Due to its flexible and efficient fine-grained access control feature,Ciphertext-Policy Attribute-Based Encryption(CP-ABE)is suitable for data sharing in IoV.However,there are many flaws in most existing CP-ABE schemes,such as attribute privacy leakage and key misuse.This paper proposes a Traceable and Revocable CP-ABE-based Data Sharing with Partially hidden policy for IoV(TRE-DSP).A partially hidden access structure is adopted to hide sensitive user attribute values,and attribute categories are sent along with the ciphertext to effectively avoid privacy exposure.In addition,key tracking and malicious user revocation are introduced with broadcast encryption to prevent key misuse.Since the main computation task is outsourced to the cloud,the burden of the user side is relatively low.Analysis of security and performance demonstrates that TRE-DSP is more secure and practical for data sharing in IoV.展开更多
Hidden champions play a critical role in China’s efforts to overcome technological and industrial“chokepoints”.These enterprises are pivotal for breaking free from Western technological embargoes,avoiding entrapmen...Hidden champions play a critical role in China’s efforts to overcome technological and industrial“chokepoints”.These enterprises are pivotal for breaking free from Western technological embargoes,avoiding entrapment in low-value-added production,and driving industrial upgrading.Given the distinct market environment in which China’s hidden champions have emerged,it is both timely and practically significant to examine their growth trajectories and underlying mechanisms.This study adopts a resource allocation perspective to investigate the development path of Chinese manufacturing enterprises into hidden champions,using a vertical case study of Hailiya Group.The findings reveal that such enterprises achieve hidden champion status by vertically concentrating on niche markets while harnessing technological potential and horizontally diversifying their technology application scenarios.Their growth follows a“T-shaped”strategy,combining vertical specialization in a focused market with horizontal expansion into new applications.Four critical mechanisms underpin the rise of manufacturing hidden champions:market niche positioning,innovation-driven focus,application scenario expansion,and ecosystem development.Specifically,these enterprises strategically target niche markets,establish a technology-oriented competitive edge,broaden technology applications to unlock new profit opportunities,and develop collaborative ecosystems to share resources and drive industrial advancement.This paper not only extends the interpretive boundaries of resource allocation theory but also offers fresh insights into the emergence of Chinese manufacturing enterprises as hidden champions,enriching our understanding of their unique growth dynamics.展开更多
Objectives This study aimed to examine the role of the hidden curriculum in transmitting the educational mission and its impacts on nursing students’professional socialization.Methods This constructivist grounded the...Objectives This study aimed to examine the role of the hidden curriculum in transmitting the educational mission and its impacts on nursing students’professional socialization.Methods This constructivist grounded theory study involved twenty-six students and five faculty members from a century-old nursing school in Macao.Semi-structured interviews examined the factors influencing nursing students’choice of a specific nursing school and their general learning experiences in nursing studies.Open and focused coding was employed to develop categories and concepts that capture the nuances of how the hidden curriculum influences students’personal experiences,perceptions,and values related to developing their professional identities.The data analysis was guided by the“Community of Practice”model.Results The educational mission fostered a hidden curriculum that emphasized nurturing qualities and social responsibilities,creating a family-like learning environment that positively influenced the professional socialization of nursing students.Under the core theme of“becoming a family,”two sub-themes emerged:“student-peer interactions-fostering sisterly/brotherly learning partnerships”and“student-faculty interactions–faculty’s acting as parenting instructors.”While the hidden curriculum promoted a democratic and egalitarian learning atmosphere among student-peers,it simultaneously reinforced hierarchical power dynamics among senior-junior students and student-faculty relationships,mirroring the power-based interpersonal dynamics often found in traditional Chinese families.Conclusions Explicating the educational mission can help shape a hidden curriculum that benefits nursing students’professional socialization.Faculty members should reflect on the power inequalities reproduced by the hidden curriculum and establish appropriate boundaries in student-faculty relationships.展开更多
Large basins are currently the global focus for geothermal development,with their hydrothermal system being controlled by a variety of factors,such as basement relief and fracture development.Donglihu is located at th...Large basins are currently the global focus for geothermal development,with their hydrothermal system being controlled by a variety of factors,such as basement relief and fracture development.Donglihu is located at the north of the Cangxian uplift in the North China Basin,the concentrated geothermal resource development zone in North China.This study systematically collects temperature logging data and long-term dynamic monitoring of water level and water quality as well as group well tracer test data carried out in this area in recent years,on the basis of which the hydrothermal controlling role of the deep hidden faults is systematically analyzed.The results show that the Cangdong fault communicates with different geothermal reservoirs in the shallow part and plays a specific role in the water-heat channel of the local area.As a result,the high-value area of the geothermal temperature gradient in the sedimentary layer of the Donglihu area is distributed around the Cangdong fault.The geothermal reservoir temperature of the Minghuazhen Formation within the influence of the fault is also significantly higher than the regional average,the hydraulic head of different geothermal reservoirs showing a consistent and synergistic trend.However,the water quality has been stable for many years without any apparent changes.This understanding has a particular significance for further deepening understanding of the geothermal genesis mechanism in sedimentary basins and guiding future geothermal exploration and development in the Donglihu area.展开更多
Dr Emily Thompson decided it was time to set sail on her first major maritime research expedition.She had always been fascinated by the mysteries of the ocean and wanted to uncover the secrets hidden beneath the waves...Dr Emily Thompson decided it was time to set sail on her first major maritime research expedition.She had always been fascinated by the mysteries of the ocean and wanted to uncover the secrets hidden beneath the waves.Her team boarded the research vessel early in the morning,excited at the adventure that awaited them.展开更多
The load profile is a key characteristic of the power grid and lies at the basis for the power flow control and generation scheduling.However,due to the wide adoption of internet-of-things(IoT)-based metering infrastr...The load profile is a key characteristic of the power grid and lies at the basis for the power flow control and generation scheduling.However,due to the wide adoption of internet-of-things(IoT)-based metering infrastructure,the cyber vulnerability of load meters has attracted the adversary’s great attention.In this paper,we investigate the vulnerability of manipulating the nodal prices by injecting false load data into the meter measurements.By taking advantage of the changing properties of real-world load profile,we propose a deeply hidden load data attack(i.e.,DH-LDA)that can evade bad data detection,clustering-based detection,and price anomaly detection.The main contributions of this work are as follows:(i)We design a stealthy attack framework that exploits historical load patterns to generate load data with minimal statistical deviation from normalmeasurements,thereby maximizing concealment;(ii)We identify the optimal time window for data injection to ensure that the altered nodal prices follow natural fluctuations,enhancing the undetectability of the attack in real-time market operations;(iii)We develop a resilience evaluation metric and formulate an optimization-based approach to quantify the electricity market’s robustness against DH-LDAs.Our experiments show that the adversary can gain profits from the electricity market while remaining undetected.展开更多
This paper is concerned with a non-intrusive anomaly detection method for carving machine systems with variant working conditions,and a novel unsupervised detection framework that integrates convolutional autoencoder(...This paper is concerned with a non-intrusive anomaly detection method for carving machine systems with variant working conditions,and a novel unsupervised detection framework that integrates convolutional autoencoder(CAE)and Gaussian mixture hidden Markov model(GMHMM)is proposed.Firstly,the built-in sensor information under normal conditions is recorded,and a 1D convolutional autoencoder is employed to compress high-dimensional time series,thereby transforming the anomaly detection problem in high-dimensional space into a density estimation problem in a latent low-dimensional space.Then,two separate estimation networks are utilized to predict the mixture memberships and state transition probabilities for each sample,enabling GMHMM to handle low-dimensional representations and multi-condition information.Furthermore,a cost function comprising CAE reconstruction and GMHMM probability assessment is constructed for the low-dimensional representation generation and subsequent density estimation in an end-to-end fashion,and the joint optimization effectively enhances the anomaly detection performance.Finally,experiments are carried out on a self-developed multi-axis carving machine platform to validate the effectiveness and superiority of the proposed method.展开更多
Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand ...Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand elastic longitudinal waves,which are of irrotational curl-free nature without vorticity and can be describedby scalar fields.Moreover,the conventional theory cannot even answer the question of whether wave spin existsin dissipative fields,given the ubiquitous dissipation in reality.Here,to resolve the seeming paradox and answerthe challenging question,we uncover the origin of wave spin in scalar fields beyond traditional formalism byclarifying that the presence of higher-order derivatives in scalar field Lagrangians can give rise to non-vanishingwave spin.For“spinless”scalar fields of only first-order derivatives,we can make the hidden wave spin emergeby revealing a latent field that leads to the original field through a time derivative,thus giving higher-order termsin Lagrangian.Based on the standard Noether theorem approach,we exemplify the wave spin for unconventionaldrifted acoustic fields,and even for dissipative media,in scalar fields with higher-order derivative Lagrangian.The results would prompt people to build more comprehensive and fundamental understandings of structuralwave spin in classical fields.展开更多
1 In 2024,audiences were treated to something very special:new music by Wolfgang Amadeus Mozart.That's right-new Mozart music!2 Leipzig Municipal Libraries announced their exciting find.Researchers came across thi...1 In 2024,audiences were treated to something very special:new music by Wolfgang Amadeus Mozart.That's right-new Mozart music!2 Leipzig Municipal Libraries announced their exciting find.Researchers came across this lost work while updating the Köchel catalogue,a list of Mozart's compositions.The piece is a seven⁃movement string trio,written in the mid to late 1760s,when Mozart was very young.The handwritten manuscript,titled Serenate ex C,uses dark brown ink on off⁃white paper.Now,it's been renamed Ganz kleine Nachtmusik and lasts about 12 minutes.展开更多
Achieving the dual carbon goal through energy transition has become a global consensus.The increasingly recognized of mineral resources is increasingly recognized due to their role in determining the pace of energy tr...Achieving the dual carbon goal through energy transition has become a global consensus.The increasingly recognized of mineral resources is increasingly recognized due to their role in determining the pace of energy transition.China has a leading capacity in the production and processing of certain minerals.However,because the major sources are abroad,China still faces certain disadvantages in acquiring upstream resources.In response to the complex international situation and high consumption demand。展开更多
Objective Identification of the risk factors for extraordinary hidden blood loss(HBL) could clarify the underlying causes and provide more appropriate management. This study aims to identify the predictors of HBL in s...Objective Identification of the risk factors for extraordinary hidden blood loss(HBL) could clarify the underlying causes and provide more appropriate management. This study aims to identify the predictors of HBL in spinal surgery.Methods Medical records were retrospectively retrieved to collect the data of patients who undergoing posterior thoracic and lumbar fusion surgery or scoliosis surgery. Demographic information, perioperative visible blood loss volume, as well as laboratory results were recorded. The patients receiving fusion surgery or scoliosis surgery were further divided into the HBL positive subgroup and the HBL negative subgroup. Differences in the variables between the groups were then analyzed. Binary logistic regression analysis was performed to determine independent risk factors associated with HBL.Results For patients undergoing posterior spinal surgery, the independent risk factors associated with HBL were autologous transfusion(for fusion surgery P = 0.011, OR: 2.627, 95%CI: 1.574-2.782; for scoliosis surgery P < 0.001, OR: 2.268, 95%CI: 2.143-2.504) and allogeneic transfusion(for fusion surgery P < 0.001, OR: 6.487, 95%CI: 2.349-17.915; for scoliosis surgery P < 0.001, OR: 3.636, 95%CI: 2.389-5.231).Conclusion Intraoperative blood transfusion might be an early-warning indicator for perioperative HBL.展开更多
The existing ontology mapping methods mainly consider the structure of the ontology and the mapping precision is lower to some extent. According to statistical theory, a method which is based on the hidden Markov mode...The existing ontology mapping methods mainly consider the structure of the ontology and the mapping precision is lower to some extent. According to statistical theory, a method which is based on the hidden Markov model is presented to establish ontology mapping. This method considers concepts as models, and attributes, relations, hierarchies, siblings and rules of the concepts as the states of the HMM, respectively. The models corresponding to the concepts are built by virtue of learning many training instances. On the basis of the best state sequence that is decided by the Viterbi algorithm and corresponding to the instance, mapping between the concepts can be established by maximum likelihood estimation. Experimental results show that this method can improve the precision of heterogeneous ontology mapping effectively.展开更多
基金Project(U2034211)supported by the National Natural Science Foundation of ChinaProject(20232ACE01013)supported by the Major Scientific and Technological Research and Development Special Project of Jiangxi Province,China。
文摘The safe driving and operation of trains is a necessary condition for ensuring the safe operation of trains.In particular,heavy-haul trains are characterized by the difficulty in driving and operation.Considering the uncertainties in train driving and operation,this paper analyzes the relationship between the safety of heavy-haul electric locomotive hauled trains and driving and operation.It studies the auxiliary intelligent driving safety operation control methods.Through K-means to identify the characteristics of drivers'driving manipulation,the hidden Markov model adaptively adjusts the train driving and operation sequence,and conducts auxiliary driving reconstruction for heavy-haul locomotive driving and operation.Based on the train running curve and the locomotive traction/braking characteristics,it smoothly controls the exertion of the traction/braking force of heavy-haul locomotives,thereby optimizing the driving safety control of heavy-haul trains in the vehicle-environment-track system.Finally,the train operation simulation and optimized driving verification are carried out by simulating some track sections.The results show that the proposed method can correct and pre-optimize driving operations,improving the smoothness of heavy-haul trains by approximately 10%.It verifies the effectiveness of the proposed train assisted driving control reconstruction method,facilitating the smooth and safe operation of heavy-haul trains.
基金supported by the Natural Science Foundation of Shandong Province(Grant No.ZR2024MF106)the Natural Science Foundation of Shandong Province(Grant Nos.ZR2023MF004 and ZR2022MA073)+5 种基金the National Natural Science Foundation of China(Grant Nos.62371274 and 62401346)the China Postdoctoral Science Foundation(Grant No.2023M742138)the Postdoctoral Innovation Project of Shandong Province(Grant No.SDCX-ZG-202400311)the Natural Science Foundation of Qingdao Municipality(Grant No.23-2-1-151-zyydjch)the Qingdao Postdoctoral Innovation Project(Grant No.QDBSH20230202012)in part by the Elite Project of Shandong University of Science and Technology。
文摘Considering the impact of electromagnetic induction on neurons,this paper presents a three-dimensional(3D)memristor Hindmarsh–Rose(HR)neuron model.This model exhibits diverse hidden chaotic dynamics due to the absence of equilibrium points,including bifurcation phenomena,coexisting attractors,transient chaos,state transitions,and offsetboosting control.Since equilibrium points are absent in this model,all observed dynamics are classified as hidden behaviors.The complex dynamics of this neuron model are illustrated through bifurcation diagrams,Lyapunov diagrams,time series plots,and phase portraits.Furthermore,an equivalent circuit for the memristor HR neuron is constructed,and the accuracy of numerical simulations is confirmed via circuit simulation results.
基金Supported by the Guiding Project of Science and Technology Research Plan of Hubei Provincial Department of Education(B2022458)。
文摘One method to change the bifurcation characteristics of chaotic systems is anti-control,which can either delay or advance bifur-cation and transform an unstable state into a stable one.The chaotic system with infinite equilibria exhibits complex bifurcation characteris-tics.The Hopf bifurcation and hidden attractors with symmetric coexistence of the system are analyzed.An improved dynamic state feed-back control method is adopted to reduce the tedious calculation process to prevent the Hopf bifurcation from being controlled.A hybrid controller that includes both nonlinear and linear controllers is set up for the system.With the method,the delay and stability of the Hopf bifurcation of the system are studied and the goal of anti-control is achieved.Numerical analysis verified the correctness.
基金supported by the Deanship of Graduate Studies and Scientific Research at Qassim University via Grant No.(QU-APC-2025).
文摘The Internet of Things (IoT) and edge-assisted networking infrastructures are capable of bringing data processing and accessibility services locally at the respective edge rather than at a centralized module. These infrastructures are very effective in providing a fast response to the respective queries of the requesting modules, but their distributed nature has introduced other problems such as security and privacy. To address these problems, various security-assisted communication mechanisms have been developed to safeguard every active module, i.e., devices and edges, from every possible vulnerability in the IoT. However, these methodologies have neglected one of the critical issues, which is the prediction of fraudulent devices, i.e., adversaries, preferably as early as possible in the IoT. In this paper, a hybrid communication mechanism is presented where the Hidden Markov Model (HMM) predicts the legitimacy of the requesting device (both source and destination), and the Advanced Encryption Standard (AES) safeguards the reliability of the transmitted data over a shared communication medium, preferably through a secret shared key, i.e., , and timestamp information. A device becomes trusted if it has passed both evaluation levels, i.e., HMM and message decryption, within a stipulated time interval. The proposed hybrid, along with existing state-of-the-art approaches, has been simulated in the realistic environment of the IoT to verify the security measures. These evaluations were carried out in the presence of intruders capable of launching various attacks simultaneously, such as man-in-the-middle, device impersonations, and masquerading attacks. Moreover, the proposed approach has been proven to be more effective than existing state-of-the-art approaches due to its exceptional performance in communication, processing, and storage overheads, i.e., 13%, 19%, and 16%, respectively. Finally, the proposed hybrid approach is pruned against well-known security attacks in the IoT.
基金supported by the National Natural Science Foundation of China(No.62272076)。
文摘With the popularity of the Internet of Vehicles(IoV),a large amount of data is being generated every day.How to securely share data between the IoV operator and various value-added service providers becomes one of the critical issues.Due to its flexible and efficient fine-grained access control feature,Ciphertext-Policy Attribute-Based Encryption(CP-ABE)is suitable for data sharing in IoV.However,there are many flaws in most existing CP-ABE schemes,such as attribute privacy leakage and key misuse.This paper proposes a Traceable and Revocable CP-ABE-based Data Sharing with Partially hidden policy for IoV(TRE-DSP).A partially hidden access structure is adopted to hide sensitive user attribute values,and attribute categories are sent along with the ciphertext to effectively avoid privacy exposure.In addition,key tracking and malicious user revocation are introduced with broadcast encryption to prevent key misuse.Since the main computation task is outsourced to the cloud,the burden of the user side is relatively low.Analysis of security and performance demonstrates that TRE-DSP is more secure and practical for data sharing in IoV.
基金supported by the following projects:The Youth Project of the National Natural Science Foundation of China(NSFC)“Research on Chinese Multinational Companies’Componovation under Resource Constraint:From a Dynamic Circulation Logic of Home and Host Countries”(Grant No.72102030)The Research Project of Humanities and Social Sciences of the Ministry of Education“Research on Chinese Multinational Companies’Learning by Doing Mechanism under Resource Constraint”(Grant No.21C10173022)The General Project of the China Postdoctoral Science Foundation“Research on the Realization Path and Motivations for the Domestic Replacement of Core Technologies for Chinese Manufacturing Enterprises”(Grant No.2022M720975).
文摘Hidden champions play a critical role in China’s efforts to overcome technological and industrial“chokepoints”.These enterprises are pivotal for breaking free from Western technological embargoes,avoiding entrapment in low-value-added production,and driving industrial upgrading.Given the distinct market environment in which China’s hidden champions have emerged,it is both timely and practically significant to examine their growth trajectories and underlying mechanisms.This study adopts a resource allocation perspective to investigate the development path of Chinese manufacturing enterprises into hidden champions,using a vertical case study of Hailiya Group.The findings reveal that such enterprises achieve hidden champion status by vertically concentrating on niche markets while harnessing technological potential and horizontally diversifying their technology application scenarios.Their growth follows a“T-shaped”strategy,combining vertical specialization in a focused market with horizontal expansion into new applications.Four critical mechanisms underpin the rise of manufacturing hidden champions:market niche positioning,innovation-driven focus,application scenario expansion,and ecosystem development.Specifically,these enterprises strategically target niche markets,establish a technology-oriented competitive edge,broaden technology applications to unlock new profit opportunities,and develop collaborative ecosystems to share resources and drive industrial advancement.This paper not only extends the interpretive boundaries of resource allocation theory but also offers fresh insights into the emergence of Chinese manufacturing enterprises as hidden champions,enriching our understanding of their unique growth dynamics.
基金supported by Foundation of Macao(No.G-BXX-00047-2112367-03)。
文摘Objectives This study aimed to examine the role of the hidden curriculum in transmitting the educational mission and its impacts on nursing students’professional socialization.Methods This constructivist grounded theory study involved twenty-six students and five faculty members from a century-old nursing school in Macao.Semi-structured interviews examined the factors influencing nursing students’choice of a specific nursing school and their general learning experiences in nursing studies.Open and focused coding was employed to develop categories and concepts that capture the nuances of how the hidden curriculum influences students’personal experiences,perceptions,and values related to developing their professional identities.The data analysis was guided by the“Community of Practice”model.Results The educational mission fostered a hidden curriculum that emphasized nurturing qualities and social responsibilities,creating a family-like learning environment that positively influenced the professional socialization of nursing students.Under the core theme of“becoming a family,”two sub-themes emerged:“student-peer interactions-fostering sisterly/brotherly learning partnerships”and“student-faculty interactions–faculty’s acting as parenting instructors.”While the hidden curriculum promoted a democratic and egalitarian learning atmosphere among student-peers,it simultaneously reinforced hierarchical power dynamics among senior-junior students and student-faculty relationships,mirroring the power-based interpersonal dynamics often found in traditional Chinese families.Conclusions Explicating the educational mission can help shape a hidden curriculum that benefits nursing students’professional socialization.Faculty members should reflect on the power inequalities reproduced by the hidden curriculum and establish appropriate boundaries in student-faculty relationships.
基金funded by Public Interest Monitoring Project(No.XCSD-2024-317)of the Tianjin Municipal Bureau of Planning and Natural Resources。
文摘Large basins are currently the global focus for geothermal development,with their hydrothermal system being controlled by a variety of factors,such as basement relief and fracture development.Donglihu is located at the north of the Cangxian uplift in the North China Basin,the concentrated geothermal resource development zone in North China.This study systematically collects temperature logging data and long-term dynamic monitoring of water level and water quality as well as group well tracer test data carried out in this area in recent years,on the basis of which the hydrothermal controlling role of the deep hidden faults is systematically analyzed.The results show that the Cangdong fault communicates with different geothermal reservoirs in the shallow part and plays a specific role in the water-heat channel of the local area.As a result,the high-value area of the geothermal temperature gradient in the sedimentary layer of the Donglihu area is distributed around the Cangdong fault.The geothermal reservoir temperature of the Minghuazhen Formation within the influence of the fault is also significantly higher than the regional average,the hydraulic head of different geothermal reservoirs showing a consistent and synergistic trend.However,the water quality has been stable for many years without any apparent changes.This understanding has a particular significance for further deepening understanding of the geothermal genesis mechanism in sedimentary basins and guiding future geothermal exploration and development in the Donglihu area.
文摘Dr Emily Thompson decided it was time to set sail on her first major maritime research expedition.She had always been fascinated by the mysteries of the ocean and wanted to uncover the secrets hidden beneath the waves.Her team boarded the research vessel early in the morning,excited at the adventure that awaited them.
基金supported by the project Major Scientific and Technological Special Project of Guizhou Province([2024]014).
文摘The load profile is a key characteristic of the power grid and lies at the basis for the power flow control and generation scheduling.However,due to the wide adoption of internet-of-things(IoT)-based metering infrastructure,the cyber vulnerability of load meters has attracted the adversary’s great attention.In this paper,we investigate the vulnerability of manipulating the nodal prices by injecting false load data into the meter measurements.By taking advantage of the changing properties of real-world load profile,we propose a deeply hidden load data attack(i.e.,DH-LDA)that can evade bad data detection,clustering-based detection,and price anomaly detection.The main contributions of this work are as follows:(i)We design a stealthy attack framework that exploits historical load patterns to generate load data with minimal statistical deviation from normalmeasurements,thereby maximizing concealment;(ii)We identify the optimal time window for data injection to ensure that the altered nodal prices follow natural fluctuations,enhancing the undetectability of the attack in real-time market operations;(iii)We develop a resilience evaluation metric and formulate an optimization-based approach to quantify the electricity market’s robustness against DH-LDAs.Our experiments show that the adversary can gain profits from the electricity market while remaining undetected.
基金Supported by the National Natural Science Foundation of China(No.62203390).
文摘This paper is concerned with a non-intrusive anomaly detection method for carving machine systems with variant working conditions,and a novel unsupervised detection framework that integrates convolutional autoencoder(CAE)and Gaussian mixture hidden Markov model(GMHMM)is proposed.Firstly,the built-in sensor information under normal conditions is recorded,and a 1D convolutional autoencoder is employed to compress high-dimensional time series,thereby transforming the anomaly detection problem in high-dimensional space into a density estimation problem in a latent low-dimensional space.Then,two separate estimation networks are utilized to predict the mixture memberships and state transition probabilities for each sample,enabling GMHMM to handle low-dimensional representations and multi-condition information.Furthermore,a cost function comprising CAE reconstruction and GMHMM probability assessment is constructed for the low-dimensional representation generation and subsequent density estimation in an end-to-end fashion,and the joint optimization effectively enhances the anomaly detection performance.Finally,experiments are carried out on a self-developed multi-axis carving machine platform to validate the effectiveness and superiority of the proposed method.
基金supported by the National Key R&D Program of China(Grant Nos.2022YFA1404400 and 2023YFA1406900)the Natural Science Foundation of Shanghai(Grant No.23ZR1481200)the Program of Shanghai Academic Research Leader(Grant No.23XD1423800)。
文摘Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand elastic longitudinal waves,which are of irrotational curl-free nature without vorticity and can be describedby scalar fields.Moreover,the conventional theory cannot even answer the question of whether wave spin existsin dissipative fields,given the ubiquitous dissipation in reality.Here,to resolve the seeming paradox and answerthe challenging question,we uncover the origin of wave spin in scalar fields beyond traditional formalism byclarifying that the presence of higher-order derivatives in scalar field Lagrangians can give rise to non-vanishingwave spin.For“spinless”scalar fields of only first-order derivatives,we can make the hidden wave spin emergeby revealing a latent field that leads to the original field through a time derivative,thus giving higher-order termsin Lagrangian.Based on the standard Noether theorem approach,we exemplify the wave spin for unconventionaldrifted acoustic fields,and even for dissipative media,in scalar fields with higher-order derivative Lagrangian.The results would prompt people to build more comprehensive and fundamental understandings of structuralwave spin in classical fields.
文摘1 In 2024,audiences were treated to something very special:new music by Wolfgang Amadeus Mozart.That's right-new Mozart music!2 Leipzig Municipal Libraries announced their exciting find.Researchers came across this lost work while updating the Köchel catalogue,a list of Mozart's compositions.The piece is a seven⁃movement string trio,written in the mid to late 1760s,when Mozart was very young.The handwritten manuscript,titled Serenate ex C,uses dark brown ink on off⁃white paper.Now,it's been renamed Ganz kleine Nachtmusik and lasts about 12 minutes.
基金the General Project of the National Natural Science Foundation of China,“Research on the Method of CO_(2)Technology Economic Evaluation Based on Net Energy and Carbon Input-Output”(72274212)。
文摘Achieving the dual carbon goal through energy transition has become a global consensus.The increasingly recognized of mineral resources is increasingly recognized due to their role in determining the pace of energy transition.China has a leading capacity in the production and processing of certain minerals.However,because the major sources are abroad,China still faces certain disadvantages in acquiring upstream resources.In response to the complex international situation and high consumption demand。
文摘Objective Identification of the risk factors for extraordinary hidden blood loss(HBL) could clarify the underlying causes and provide more appropriate management. This study aims to identify the predictors of HBL in spinal surgery.Methods Medical records were retrospectively retrieved to collect the data of patients who undergoing posterior thoracic and lumbar fusion surgery or scoliosis surgery. Demographic information, perioperative visible blood loss volume, as well as laboratory results were recorded. The patients receiving fusion surgery or scoliosis surgery were further divided into the HBL positive subgroup and the HBL negative subgroup. Differences in the variables between the groups were then analyzed. Binary logistic regression analysis was performed to determine independent risk factors associated with HBL.Results For patients undergoing posterior spinal surgery, the independent risk factors associated with HBL were autologous transfusion(for fusion surgery P = 0.011, OR: 2.627, 95%CI: 1.574-2.782; for scoliosis surgery P < 0.001, OR: 2.268, 95%CI: 2.143-2.504) and allogeneic transfusion(for fusion surgery P < 0.001, OR: 6.487, 95%CI: 2.349-17.915; for scoliosis surgery P < 0.001, OR: 3.636, 95%CI: 2.389-5.231).Conclusion Intraoperative blood transfusion might be an early-warning indicator for perioperative HBL.
基金国家自然科学基金(the National Natural Science Foundation of China under Grant No.50279041)陕西省自然科学基金(the Natural Science Foundation of Shaanxi Province of China under Grant No.2005F07)。
基金The Weaponry Equipment Foundation of PLA Equipment Ministry (No51406020105JB8103)
文摘The existing ontology mapping methods mainly consider the structure of the ontology and the mapping precision is lower to some extent. According to statistical theory, a method which is based on the hidden Markov model is presented to establish ontology mapping. This method considers concepts as models, and attributes, relations, hierarchies, siblings and rules of the concepts as the states of the HMM, respectively. The models corresponding to the concepts are built by virtue of learning many training instances. On the basis of the best state sequence that is decided by the Viterbi algorithm and corresponding to the instance, mapping between the concepts can be established by maximum likelihood estimation. Experimental results show that this method can improve the precision of heterogeneous ontology mapping effectively.
