Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the explo...Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the exploration of appro-priate electrode materials with the correct size for reversibly accommodating large K+ions presents a significant challenge.In addition,the reaction mecha-nisms and origins of enhanced performance remain elusive.Here,tetragonal FeSe nanoflakes of different sizes are designed to serve as an anode for PIBs,and their live and atomic-scale potassiation/depotassiation mechanisms are revealed for the first time through in situ high-resolution transmission electron micros-copy.We found that FeSe undergoes two distinct structural evolutions,sequen-tially characterized by intercalation and conversion reactions,and the initial intercalation behavior is size-dependent.Apparent expansion induced by the intercalation of K+ions is observed in small-sized FeSe nanoflakes,whereas unexpected cracks are formed along the direction of ionic diffusion in large-sized nanoflakes.The significant stress generation and crack extension originating from the combined effect of mechanical and electrochemical interactions are elucidated by geometric phase analysis and finite-element analysis.Despite the different intercalation behaviors,the formed products of Fe and K_(2)Se after full potassiation can be converted back into the original FeSe phase upon depotassiation.In particular,small-sized nanoflakes exhibit better cycling perfor-mance with well-maintained structural integrity.This article presents the first successful demonstration of atomic-scale visualization that can reveal size-dependent potassiation dynamics.Moreover,it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs.展开更多
Marxist political economy provides a perspective for grasping the root cause of the China-US trade war.The international relations of production,which stem from the international division of labor,shape the distributi...Marxist political economy provides a perspective for grasping the root cause of the China-US trade war.The international relations of production,which stem from the international division of labor,shape the distribution of international economic interests and the political status of countries.Traditionally,developing countries have been subjected to the“periphery”in the international division of labor.In the new global value chain,developing countries have remained in a subordinate position characterized by“technological-market”dependence.To achieve the goal of building a strong modern nation,China must escape the“technological-market”dependence.Yet China’s efforts and achievements in escaping dependent development are deemed as a threat to US vested interests in the international markets.To preserve the economic foundation of its hegemony,the US has resorted to a trade war to contain China’s development.展开更多
Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study ...Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study adopted a quasi-experimental research design,specifically a non-equivalent control group pre-test and post-test design.Utilizing the Exercise of Self-Care Agency Scale(ESCA)and Care Dependency Scale(CDS),a survey was administered to 64 patients from a hospital in Shandong Province.The statistical methods used for analyzing data included frequency,mean,standard deviation(SD),independent t-test,P-value calculation,and dependent t-test.Result:After two months of a brisk walking exercise program,participants in the experimental group had a higher level of self-care agency than before the experiment(P<0.05),and their level of care dependency was significantly reduced(P<0.05).Participants in the control group also showed higher levels of self-care agency(P<0.05)and lower levels of care dependency(P<0.05)after two months compared to their levels before the two months.Conclusion:The brisk walking program had a positive impact on patients’self-care agency and reduced their care dependency.展开更多
This paper focuses on the dynamic tensile response of glass-graphite/epoxy composites illustrating improvement in energy absorption through hybridization. The dynamic response and energy absorption characteristics of ...This paper focuses on the dynamic tensile response of glass-graphite/epoxy composites illustrating improvement in energy absorption through hybridization. The dynamic response and energy absorption characteristics of pultruded hybrid combinations of glass and graphite fibers in an epoxy matrix subjected to induced transverse tension at high strain-rate in a modified Split Hopkinson Pressure Bar (SHPB) apparatus, are presented. Transverse tensile strength was determined by diametral compression of disc samples (Brazilian indirect tensile test method). Diametral crack initiation and strain to failure were monitored with a Shimadzu HPV-2 high-speed video camera at a recording speed of 500,000 fps and Digital Image Correlation (DIC). Adequate measures were taken to ensure that initiation of specimen failure occurred at the exact center of the disc specimen, and propagated through the diameter along the compressive loading axis, for the induced transverse tension tests to be valid. A study of the strength and specific energy absorption demonstrates the benefits of hybridization. Under induced transverse tensile loading condition, the pure glass/epoxy (GL60) exhibited higher strength than pure graphite/epoxy (GR60). Pure graphite/epoxy (GR60) has higher specific energy absorption capacity than pure glass/epoxy (GL60) in transverse tension. Among all hybrids, GR30 has the highest specific energy absorption under transverse tension. Overall, hybrid GL48, with 48% low-cost glass fibers in the inner core and 12% high-cost graphite fibers in outer shell, was found to exhibit better performance under induced transverse tension at high strain-rates, showing the benefits of hybridization.展开更多
Presented here are the Generalized BCS Equations incorporating Fermi Energy for the study of the {Δ, Tc, jc(T)} values of both elemental and composite superconductors (SCs) for all T ≤ Tc, where Δ, Tc and jc(T) den...Presented here are the Generalized BCS Equations incorporating Fermi Energy for the study of the {Δ, Tc, jc(T)} values of both elemental and composite superconductors (SCs) for all T ≤ Tc, where Δ, Tc and jc(T) denote, respectively, one of the gap values, the critical temperature and the T-dependent critical current density. This framework, which extends our earlier study that dealt with the {Δ0, Tc, jc(0)} values of an SC, is also shown to lead to T-dependent values of several other related parameters such as the effective mass of electrons, their number density, critical velocity, Fermi velocity (VF), coherence length and the London penetration depth. The extended framework is applied to the jc(T) data reported by Romijn et al. for superconducting Aluminium strips and is shown not only to provide an alternative to the explanation given by them, but also to some novel features such as the role of the Sommerfeld coefficient γ(T) in the context of jc(T) and the role of VF(T) in the context of a recent finding by Plumb et al. about the superconductivity of Bi-2212.展开更多
In a dynamic CT, the acquired projections are corrupted due to strong dynamic nature of the object, for example: lungs, heart etc. In this paper, we present fan-beam reconstruction algorithm without position-dependent...In a dynamic CT, the acquired projections are corrupted due to strong dynamic nature of the object, for example: lungs, heart etc. In this paper, we present fan-beam reconstruction algorithm without position-dependent backprojection weight which compensates for the time-dependent translational, uniform scaling and rotational deformations occurring in the object of interest during the data acquisition process. We shall also compare the computational cost of the proposed reconstruction algorithm with the existing one which has position-dependent weight. To accomplish the objective listed above, we first formulate admissibility conditions on deformations that is required to exactly reconstruct the object from acquired sequential deformed projections and then derive the reconstruction algorithm to compensate the above listed deformations satisfying the admissibility conditions. For this, 2-D time-dependent deformation model is incorporated in the fan-beam FBP reconstruction algorithm with no backprojection weight, assuming the motion parameters being known. Finally the proposed reconstruction algorithm is evaluated with the motion corrupted projection data simulated on the computer.展开更多
In this paper a new modeling framework for the dependability analysis of complex systems is presented and related to dynamic fault trees (DFTs). The methodology is based on a modular approach: two separate models are ...In this paper a new modeling framework for the dependability analysis of complex systems is presented and related to dynamic fault trees (DFTs). The methodology is based on a modular approach: two separate models are used to handle, the fault logic and the stochastic dependencies of the system. Thus, the fault schema, free of any dependency logic, can be easily evaluated, while the dependency schema allows the modeler to design new kind of non-trivial dependencies not easily caught by the traditional holistic methodologies. Moreover, the use of a dependency schema allows building a pure behavioral model that can be used for various kinds of dependability studies. In the paper is shown how to build and integrate the two modular models and convert them in a Stochastic Activity Network. Furthermore, based on the construction of the schema that embeds the stochastic dependencies, the procedure to convert DFTs into static fault trees is shown, allowing the resolution of DFTs in a very efficient way.展开更多
The false discovery proportion (FDP) is a useful measure of abundance of false positives when a large number of hypotheses are being tested simultaneously. Methods for controlling the expected value of the FDP, namely...The false discovery proportion (FDP) is a useful measure of abundance of false positives when a large number of hypotheses are being tested simultaneously. Methods for controlling the expected value of the FDP, namely the false discovery rate (FDR), have become widely used. It is highly desired to have an accurate prediction interval for the FDP in such applications. Some degree of dependence among test statistics exists in almost all applications involving multiple testing. Methods for constructing tight prediction intervals for the FDP that take account of dependence among test statistics are of great practical importance. This paper derives a formula for the variance of the FDP and uses it to obtain an upper prediction interval for the FDP, under some semi-parametric assumptions on dependence among test statistics. Simulation studies indicate that the proposed formula-based prediction interval has good coverage probability under commonly assumed weak dependence. The prediction interval is generally more accurate than those obtained from existing methods. In addition, a permutation-based upper prediction interval for the FDP is provided, which can be useful when dependence is strong and the number of tests is not too large. The proposed prediction intervals are illustrated using a prostate cancer dataset.展开更多
Effects of calcium( Ca) and yttrium( Y) on microstructure and mechanical properties of high strain-rate rolled AZ91 D magnesium alloy were studied. High strain-rate rolling can improve the strength and plasticity of m...Effects of calcium( Ca) and yttrium( Y) on microstructure and mechanical properties of high strain-rate rolled AZ91 D magnesium alloy were studied. High strain-rate rolling can improve the strength and plasticity of magnesium alloy sheets.Additions of Ca and Y into AZ91 D can refine grains and modify the size and the distribution of the precipitated phases. After solution treatment( 418 ℃ and 20 h) and high strain-rate rolling( heating at420 ℃ for 10 min firstly and then rolling from 10 mm to 2 mm in thickness via a single pass),the tensile strength of the AZ91 D-0. 2%Ca alloy was 1. 3% higher than that of the AZ91 D-0. 4 D%Y alloy,and the tensile strength of the AZ91 D-0. 2%Ca-0. 4%Y alloy was about 8. 3% and 6. 9% higher than those of the AZ91 D-0. 4%Y and the AZ91 D-0. 2%Ca alloys respectively.展开更多
A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α whi...A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α while guaranteeing the maximum power of the two constituent tests. Critical values, obtained via Monte Carlo methods, are uniformly smaller than the Bonferroni-Dunn adjustment, giving it power superiority when testing for treatment alternatives of shift in location parameter when data are sampled from non-normal distributions.展开更多
We study waiting time problems for first-order Markov dependent trials via conditional probability generating functions. Our models involve α frequency cells and β run cells with prescribed quotas and an additional ...We study waiting time problems for first-order Markov dependent trials via conditional probability generating functions. Our models involve α frequency cells and β run cells with prescribed quotas and an additional γ slack cells without quotas. For any given and , in our Model I we determine the waiting time until at least frequency cells and at least run cells reach their quotas. For any given τ ≤ α + β, in our Model II we determine the waiting time until τ cells reach their quotas. Computer algorithms are developed to calculate the distributions, expectations and standard deviations of the waiting time random variables of the two models. Numerical results demonstrate the efficiency of the algorithms.展开更多
Thucydides asserts that the occupation of Decelea by the Spartans in 413 BC made the grain supply for Athens costly by forcing the transport from land onto the sea.This calls into question the well-established consens...Thucydides asserts that the occupation of Decelea by the Spartans in 413 BC made the grain supply for Athens costly by forcing the transport from land onto the sea.This calls into question the well-established consensus that sea transport was far cheaper than land transport.This paper contends that the cost of protecting supply lines-specifically the expenses associated with the warships which escorted the supply ships-rendered the grain transported on the new route exceptionally costly.In this paper,the benefits and drawbacks of a maritime economy,including transaction costs,trade dependencies,and the capabilities of warships and supply ships are discussed.展开更多
In a previous study, the energy absorption and dynamic response of different combinations of cylindrical fiber-reinforced pultruded hybrid composite samples made of unidirectional glass and graphite fiber/epoxy, were ...In a previous study, the energy absorption and dynamic response of different combinations of cylindrical fiber-reinforced pultruded hybrid composite samples made of unidirectional glass and graphite fiber/epoxy, were investigated under longitudinal compression loading. It was found that placing glass fibers in the inner core of composites resulted in a higher ultimate compressive strength and specific energy absorption. In this study, the dynamic responses of pultruded glass-graphite/epoxy hybrid specimens with rectangular cross-section subjected to transverse compression loading are reported. Crack initiation and propagation was monitored using a high-speed video camera, and the effects of hybridization were analyzed. It was found that the location of glass or graphite fibers inside the pultruded composites has no significant effect on the ultimate compressive strength under such transverse compression loading. The energy absorption in all the hybrid specimens was almost identical. Graphite/epoxy composite showed higher specific energy absorption due to its lower density, and glass/epoxy composite had the lowest specific energy absorption.展开更多
With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in th...With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in the field of human reliability analysis(HRA)to evaluate human reliability and assess risk in large complex systems.However,the classical SPAR-H method does not consider the dependencies among performance shaping factors(PSFs),whichmay cause overestimation or underestimation of the risk of the actual situation.To address this issue,this paper proposes a new method to deal with the dependencies among PSFs in SPAR-H based on the Pearson correlation coefficient.First,the dependence between every two PSFs is measured by the Pearson correlation coefficient.Second,the weights of the PSFs are obtained by considering the total dependence degree.Finally,PSFs’multipliers are modified based on the weights of corresponding PSFs,and then used in the calculating of human error probability(HEP).A case study is used to illustrate the procedure and effectiveness of the proposed method.展开更多
In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal ...In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal graph.Most GCNs define the graph topology by physical relations of the human joints.However,this predefined graph ignores the spatial relationship between non-adjacent joint pairs in special actions and the behavior dependence between joint pairs,resulting in a low recognition rate for specific actions with implicit correlation between joint pairs.In addition,existing methods ignore the trend correlation between adjacent frames within an action and context clues,leading to erroneous action recognition with similar poses.Therefore,this study proposes a learnable GCN based on behavior dependence,which considers implicit joint correlation by constructing a dynamic learnable graph with extraction of specific behavior dependence of joint pairs.By using the weight relationship between the joint pairs,an adaptive model is constructed.It also designs a self-attention module to obtain their inter-frame topological relationship for exploring the context of actions.Combining the shared topology and the multi-head self-attention map,the module obtains the context-based clue topology to update the dynamic graph convolution,achieving accurate recognition of different actions with similar poses.Detailed experiments on public datasets demonstrate that the proposed method achieves better results and realizes higher quality representation of actions under various evaluation protocols compared to state-of-the-art methods.展开更多
AIM:To investigate the prognostic role of invariant natural killer T(iNKT) cells and antibody-dependent cell-mediated cytotoxicity(ADCC) in wild type KRAS metastatic colorectal cancer(mC RC) patients treated with cetu...AIM:To investigate the prognostic role of invariant natural killer T(iNKT) cells and antibody-dependent cell-mediated cytotoxicity(ADCC) in wild type KRAS metastatic colorectal cancer(mC RC) patients treated with cetuximab.METHODS: Forty-one KRAS wt mC RC patients,treated with cetuximab and irinotecan-based chemotherapy in Ⅱ and Ⅲ lines were analyzed. Genotyping of single nucleotide polymorphism(SNP)s in the FCGR2A,FCGR3A and in the 3' untranslated regions of KRAS and mutational analysis for KRAS,BRAF and NRAS genes was determined either by sequencing or allelic discrimination assays. Enriched NK cells were obtained from lymphoprepperipheral blood mononuclear cell and iN KT cells were defined by co-expression of CD3,TCRVα24,TCRVβ11. ADCC was evaluated as ex vivo NK-dependent activity,measuring lactate dehydrogenase release.RESULTS: At basal,mCRC patients performing ADCC activity above the median level(71%) showed an improved overall survival(OS) compared to patients with ADCC below(median 16 vs 8 mo;P=0.026). We did not find any significant correlation of iN KT cells with OS(P=0.19),albeit we observed a trend to a longer survival after 10 mo in patients with iN KT above median basal level(0.382 cells/microliter). Correlation of OS and progression-free survival(PFS) with interesting SNPs involved in ADCC ability revealed not to be significant. Patients carrying alleles both with A in FCGR2 A and TT in FCGR3A presented a trend of longer PFS(median 9 vs 5 mo;P=0.064). Chemotherapy impacted both iN KT cells and ADCC activity. Their prognostic values get lost when we analysed them after 2 and 4 mo of treatment.CONCLUSION: Our results suggest a link between iN KT cells,basal ADCC activity,genotypes in FCGR2A and FCGR3A,and efficacy of cetuximab in KRAS wt mC RC patients.展开更多
In this paper, we introduce tail dependene measures for collateral losses from catastrophic events. To calculate these measures, we use bivariate compound process where a Cox process with shot noise intensity is used ...In this paper, we introduce tail dependene measures for collateral losses from catastrophic events. To calculate these measures, we use bivariate compound process where a Cox process with shot noise intensity is used to count collateral losses. A homogeneous Poisson process is also examined as its counterpart for the case where the catastrophic loss frequency rate is deterministic. Joint Laplace transform of the distribution of the aggregate collateral losses is derived and joint Fast Fourier transform is used to obtain the joint distributions of aggregate collateral losses. For numerical illustrations, a member of Farlie-Gumbel-Morgenstern copula with exponential margins is used. The figures of the joint distributions of collateral losses, their contours and numerical calculations of risk measures are also provided.展开更多
This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of t...This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data.展开更多
Due to greedy algorithm is adopted in the analysis of dependency parsing based on transformation, thus we select the most likely analysis action in each analysis step and ignore the dependency relation analysis of sen...Due to greedy algorithm is adopted in the analysis of dependency parsing based on transformation, thus we select the most likely analysis action in each analysis step and ignore the dependency relation analysis of sentences. Therefore, in this paper, we propose decision based multi-candidate Chinese dependency syntax method on the basis of traditional Are-eager algorithms proposed by Nivre. In the new method, multiple candidate structures are introduced. We select multiple possible motion analysis according to every analysis step, and the optimal solution is selected in the sentence, in order to determine the dependency relation between different words and improve the correct rate. We choose the Chinese Pennsylvania Treebank and establish dependency analyzer based on support vector machine, we prove the effectiveness of the algorithm.展开更多
Degradation and overstress failures occur in many electronic systems in which the operation load and environmental conditions are complex.The dependency of them called dependent competing failure process(DCFP),has bee...Degradation and overstress failures occur in many electronic systems in which the operation load and environmental conditions are complex.The dependency of them called dependent competing failure process(DCFP),has been widely studied.Electronic system may experience mutual effects of degradation and shocks,they are considered to be interdependent.Both the degradation and the shock processes will decrease the limit of system and cause cumulative effect.Finally,the competition of hard and soft failure will cause the system failure.Based on the failure mechanism accumulation theory,this paper constructs the shock-degradation acceleration and the threshold descent model,and a system reliability model established by using these two models.The mutually DCFP effect of electronic system interaction has been decomposed into physical correlation of failure,including acceleration,accumulation and competition.As a case,a reliability of electronic system in aeronautical system has been analyzed with the proposed method.The method proposed is based on failure physical evaluation,and could provide important reference for quantitative evaluation and design improvement of the newly designed system in case of data deficiency.展开更多
基金This work was supported by the National Key R&D Program of China(Grant No.2018YFB1304902)the National Natural Science Foundation of China(Grant Nos.12004034,U1813211,22005247,11904372,51502007,52072323,52122211,12174019,and 51972058)+1 种基金the Gen-eral Research Fund of Hong Kong(Project No.11217221)China Postdoctoral Science Foundation Funded Project(Grant No.2021M690386).
文摘Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the exploration of appro-priate electrode materials with the correct size for reversibly accommodating large K+ions presents a significant challenge.In addition,the reaction mecha-nisms and origins of enhanced performance remain elusive.Here,tetragonal FeSe nanoflakes of different sizes are designed to serve as an anode for PIBs,and their live and atomic-scale potassiation/depotassiation mechanisms are revealed for the first time through in situ high-resolution transmission electron micros-copy.We found that FeSe undergoes two distinct structural evolutions,sequen-tially characterized by intercalation and conversion reactions,and the initial intercalation behavior is size-dependent.Apparent expansion induced by the intercalation of K+ions is observed in small-sized FeSe nanoflakes,whereas unexpected cracks are formed along the direction of ionic diffusion in large-sized nanoflakes.The significant stress generation and crack extension originating from the combined effect of mechanical and electrochemical interactions are elucidated by geometric phase analysis and finite-element analysis.Despite the different intercalation behaviors,the formed products of Fe and K_(2)Se after full potassiation can be converted back into the original FeSe phase upon depotassiation.In particular,small-sized nanoflakes exhibit better cycling perfor-mance with well-maintained structural integrity.This article presents the first successful demonstration of atomic-scale visualization that can reveal size-dependent potassiation dynamics.Moreover,it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs.
基金This study is funded by Major Research Program on Philosophy and Social Sciences of Jiangsu Education Department(The Education of Marxism International View in Colleges and Universities for a New Era,No.2022SJZDSZ001)Green Research Program of Nanjing University of Aeronautics and Astronautics(China-US Science and Technology Competition from the Perspective of Marxism,No.1023-YAH21032).
文摘Marxist political economy provides a perspective for grasping the root cause of the China-US trade war.The international relations of production,which stem from the international division of labor,shape the distribution of international economic interests and the political status of countries.Traditionally,developing countries have been subjected to the“periphery”in the international division of labor.In the new global value chain,developing countries have remained in a subordinate position characterized by“technological-market”dependence.To achieve the goal of building a strong modern nation,China must escape the“technological-market”dependence.Yet China’s efforts and achievements in escaping dependent development are deemed as a threat to US vested interests in the international markets.To preserve the economic foundation of its hegemony,the US has resorted to a trade war to contain China’s development.
文摘Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study adopted a quasi-experimental research design,specifically a non-equivalent control group pre-test and post-test design.Utilizing the Exercise of Self-Care Agency Scale(ESCA)and Care Dependency Scale(CDS),a survey was administered to 64 patients from a hospital in Shandong Province.The statistical methods used for analyzing data included frequency,mean,standard deviation(SD),independent t-test,P-value calculation,and dependent t-test.Result:After two months of a brisk walking exercise program,participants in the experimental group had a higher level of self-care agency than before the experiment(P<0.05),and their level of care dependency was significantly reduced(P<0.05).Participants in the control group also showed higher levels of self-care agency(P<0.05)and lower levels of care dependency(P<0.05)after two months compared to their levels before the two months.Conclusion:The brisk walking program had a positive impact on patients’self-care agency and reduced their care dependency.
文摘This paper focuses on the dynamic tensile response of glass-graphite/epoxy composites illustrating improvement in energy absorption through hybridization. The dynamic response and energy absorption characteristics of pultruded hybrid combinations of glass and graphite fibers in an epoxy matrix subjected to induced transverse tension at high strain-rate in a modified Split Hopkinson Pressure Bar (SHPB) apparatus, are presented. Transverse tensile strength was determined by diametral compression of disc samples (Brazilian indirect tensile test method). Diametral crack initiation and strain to failure were monitored with a Shimadzu HPV-2 high-speed video camera at a recording speed of 500,000 fps and Digital Image Correlation (DIC). Adequate measures were taken to ensure that initiation of specimen failure occurred at the exact center of the disc specimen, and propagated through the diameter along the compressive loading axis, for the induced transverse tension tests to be valid. A study of the strength and specific energy absorption demonstrates the benefits of hybridization. Under induced transverse tensile loading condition, the pure glass/epoxy (GL60) exhibited higher strength than pure graphite/epoxy (GR60). Pure graphite/epoxy (GR60) has higher specific energy absorption capacity than pure glass/epoxy (GL60) in transverse tension. Among all hybrids, GR30 has the highest specific energy absorption under transverse tension. Overall, hybrid GL48, with 48% low-cost glass fibers in the inner core and 12% high-cost graphite fibers in outer shell, was found to exhibit better performance under induced transverse tension at high strain-rates, showing the benefits of hybridization.
文摘Presented here are the Generalized BCS Equations incorporating Fermi Energy for the study of the {Δ, Tc, jc(T)} values of both elemental and composite superconductors (SCs) for all T ≤ Tc, where Δ, Tc and jc(T) denote, respectively, one of the gap values, the critical temperature and the T-dependent critical current density. This framework, which extends our earlier study that dealt with the {Δ0, Tc, jc(0)} values of an SC, is also shown to lead to T-dependent values of several other related parameters such as the effective mass of electrons, their number density, critical velocity, Fermi velocity (VF), coherence length and the London penetration depth. The extended framework is applied to the jc(T) data reported by Romijn et al. for superconducting Aluminium strips and is shown not only to provide an alternative to the explanation given by them, but also to some novel features such as the role of the Sommerfeld coefficient γ(T) in the context of jc(T) and the role of VF(T) in the context of a recent finding by Plumb et al. about the superconductivity of Bi-2212.
文摘In a dynamic CT, the acquired projections are corrupted due to strong dynamic nature of the object, for example: lungs, heart etc. In this paper, we present fan-beam reconstruction algorithm without position-dependent backprojection weight which compensates for the time-dependent translational, uniform scaling and rotational deformations occurring in the object of interest during the data acquisition process. We shall also compare the computational cost of the proposed reconstruction algorithm with the existing one which has position-dependent weight. To accomplish the objective listed above, we first formulate admissibility conditions on deformations that is required to exactly reconstruct the object from acquired sequential deformed projections and then derive the reconstruction algorithm to compensate the above listed deformations satisfying the admissibility conditions. For this, 2-D time-dependent deformation model is incorporated in the fan-beam FBP reconstruction algorithm with no backprojection weight, assuming the motion parameters being known. Finally the proposed reconstruction algorithm is evaluated with the motion corrupted projection data simulated on the computer.
文摘In this paper a new modeling framework for the dependability analysis of complex systems is presented and related to dynamic fault trees (DFTs). The methodology is based on a modular approach: two separate models are used to handle, the fault logic and the stochastic dependencies of the system. Thus, the fault schema, free of any dependency logic, can be easily evaluated, while the dependency schema allows the modeler to design new kind of non-trivial dependencies not easily caught by the traditional holistic methodologies. Moreover, the use of a dependency schema allows building a pure behavioral model that can be used for various kinds of dependability studies. In the paper is shown how to build and integrate the two modular models and convert them in a Stochastic Activity Network. Furthermore, based on the construction of the schema that embeds the stochastic dependencies, the procedure to convert DFTs into static fault trees is shown, allowing the resolution of DFTs in a very efficient way.
文摘The false discovery proportion (FDP) is a useful measure of abundance of false positives when a large number of hypotheses are being tested simultaneously. Methods for controlling the expected value of the FDP, namely the false discovery rate (FDR), have become widely used. It is highly desired to have an accurate prediction interval for the FDP in such applications. Some degree of dependence among test statistics exists in almost all applications involving multiple testing. Methods for constructing tight prediction intervals for the FDP that take account of dependence among test statistics are of great practical importance. This paper derives a formula for the variance of the FDP and uses it to obtain an upper prediction interval for the FDP, under some semi-parametric assumptions on dependence among test statistics. Simulation studies indicate that the proposed formula-based prediction interval has good coverage probability under commonly assumed weak dependence. The prediction interval is generally more accurate than those obtained from existing methods. In addition, a permutation-based upper prediction interval for the FDP is provided, which can be useful when dependence is strong and the number of tests is not too large. The proposed prediction intervals are illustrated using a prostate cancer dataset.
基金Natural Science Foundation of Hunan Province,China(No.2017JJ5032)
文摘Effects of calcium( Ca) and yttrium( Y) on microstructure and mechanical properties of high strain-rate rolled AZ91 D magnesium alloy were studied. High strain-rate rolling can improve the strength and plasticity of magnesium alloy sheets.Additions of Ca and Y into AZ91 D can refine grains and modify the size and the distribution of the precipitated phases. After solution treatment( 418 ℃ and 20 h) and high strain-rate rolling( heating at420 ℃ for 10 min firstly and then rolling from 10 mm to 2 mm in thickness via a single pass),the tensile strength of the AZ91 D-0. 2%Ca alloy was 1. 3% higher than that of the AZ91 D-0. 4 D%Y alloy,and the tensile strength of the AZ91 D-0. 2%Ca-0. 4%Y alloy was about 8. 3% and 6. 9% higher than those of the AZ91 D-0. 4%Y and the AZ91 D-0. 2%Ca alloys respectively.
文摘A maximum test in lieu of forcing a choice between the two dependent samples t-test and Wilcoxon signed-ranks test is proposed. The maximum test, which requires a new table of critical values, maintains nominal α while guaranteeing the maximum power of the two constituent tests. Critical values, obtained via Monte Carlo methods, are uniformly smaller than the Bonferroni-Dunn adjustment, giving it power superiority when testing for treatment alternatives of shift in location parameter when data are sampled from non-normal distributions.
文摘We study waiting time problems for first-order Markov dependent trials via conditional probability generating functions. Our models involve α frequency cells and β run cells with prescribed quotas and an additional γ slack cells without quotas. For any given and , in our Model I we determine the waiting time until at least frequency cells and at least run cells reach their quotas. For any given τ ≤ α + β, in our Model II we determine the waiting time until τ cells reach their quotas. Computer algorithms are developed to calculate the distributions, expectations and standard deviations of the waiting time random variables of the two models. Numerical results demonstrate the efficiency of the algorithms.
文摘Thucydides asserts that the occupation of Decelea by the Spartans in 413 BC made the grain supply for Athens costly by forcing the transport from land onto the sea.This calls into question the well-established consensus that sea transport was far cheaper than land transport.This paper contends that the cost of protecting supply lines-specifically the expenses associated with the warships which escorted the supply ships-rendered the grain transported on the new route exceptionally costly.In this paper,the benefits and drawbacks of a maritime economy,including transaction costs,trade dependencies,and the capabilities of warships and supply ships are discussed.
文摘In a previous study, the energy absorption and dynamic response of different combinations of cylindrical fiber-reinforced pultruded hybrid composite samples made of unidirectional glass and graphite fiber/epoxy, were investigated under longitudinal compression loading. It was found that placing glass fibers in the inner core of composites resulted in a higher ultimate compressive strength and specific energy absorption. In this study, the dynamic responses of pultruded glass-graphite/epoxy hybrid specimens with rectangular cross-section subjected to transverse compression loading are reported. Crack initiation and propagation was monitored using a high-speed video camera, and the effects of hybridization were analyzed. It was found that the location of glass or graphite fibers inside the pultruded composites has no significant effect on the ultimate compressive strength under such transverse compression loading. The energy absorption in all the hybrid specimens was almost identical. Graphite/epoxy composite showed higher specific energy absorption due to its lower density, and glass/epoxy composite had the lowest specific energy absorption.
基金Shanghai Rising-Star Program(Grant No.21QA1403400)Shanghai Sailing Program(Grant No.20YF1414800)Shanghai Key Laboratory of Power Station Automation Technology(Grant No.13DZ2273800).
文摘With the improvement of equipment reliability,human factors have become the most uncertain part in the system.The standardized Plant Analysis of Risk-Human Reliability Analysis(SPAR-H)method is a reliable method in the field of human reliability analysis(HRA)to evaluate human reliability and assess risk in large complex systems.However,the classical SPAR-H method does not consider the dependencies among performance shaping factors(PSFs),whichmay cause overestimation or underestimation of the risk of the actual situation.To address this issue,this paper proposes a new method to deal with the dependencies among PSFs in SPAR-H based on the Pearson correlation coefficient.First,the dependence between every two PSFs is measured by the Pearson correlation coefficient.Second,the weights of the PSFs are obtained by considering the total dependence degree.Finally,PSFs’multipliers are modified based on the weights of corresponding PSFs,and then used in the calculating of human error probability(HEP).A case study is used to illustrate the procedure and effectiveness of the proposed method.
基金supported in part by the 2023 Key Supported Project of the 14th Five Year Plan for Education and Science in Hunan Province with No.ND230795.
文摘In recent years,skeleton-based action recognition has made great achievements in Computer Vision.A graph convolutional network(GCN)is effective for action recognition,modelling the human skeleton as a spatio-temporal graph.Most GCNs define the graph topology by physical relations of the human joints.However,this predefined graph ignores the spatial relationship between non-adjacent joint pairs in special actions and the behavior dependence between joint pairs,resulting in a low recognition rate for specific actions with implicit correlation between joint pairs.In addition,existing methods ignore the trend correlation between adjacent frames within an action and context clues,leading to erroneous action recognition with similar poses.Therefore,this study proposes a learnable GCN based on behavior dependence,which considers implicit joint correlation by constructing a dynamic learnable graph with extraction of specific behavior dependence of joint pairs.By using the weight relationship between the joint pairs,an adaptive model is constructed.It also designs a self-attention module to obtain their inter-frame topological relationship for exploring the context of actions.Combining the shared topology and the multi-head self-attention map,the module obtains the context-based clue topology to update the dynamic graph convolution,achieving accurate recognition of different actions with similar poses.Detailed experiments on public datasets demonstrate that the proposed method achieves better results and realizes higher quality representation of actions under various evaluation protocols compared to state-of-the-art methods.
基金the Fondazione Veronesi that granted Daniela Vivenza and Martino Monteverde with PostDoctoral Fellowship Veronesithe Fondazione Cassa Risparmio of Cuneo for partially supporting the study
文摘AIM:To investigate the prognostic role of invariant natural killer T(iNKT) cells and antibody-dependent cell-mediated cytotoxicity(ADCC) in wild type KRAS metastatic colorectal cancer(mC RC) patients treated with cetuximab.METHODS: Forty-one KRAS wt mC RC patients,treated with cetuximab and irinotecan-based chemotherapy in Ⅱ and Ⅲ lines were analyzed. Genotyping of single nucleotide polymorphism(SNP)s in the FCGR2A,FCGR3A and in the 3' untranslated regions of KRAS and mutational analysis for KRAS,BRAF and NRAS genes was determined either by sequencing or allelic discrimination assays. Enriched NK cells were obtained from lymphoprepperipheral blood mononuclear cell and iN KT cells were defined by co-expression of CD3,TCRVα24,TCRVβ11. ADCC was evaluated as ex vivo NK-dependent activity,measuring lactate dehydrogenase release.RESULTS: At basal,mCRC patients performing ADCC activity above the median level(71%) showed an improved overall survival(OS) compared to patients with ADCC below(median 16 vs 8 mo;P=0.026). We did not find any significant correlation of iN KT cells with OS(P=0.19),albeit we observed a trend to a longer survival after 10 mo in patients with iN KT above median basal level(0.382 cells/microliter). Correlation of OS and progression-free survival(PFS) with interesting SNPs involved in ADCC ability revealed not to be significant. Patients carrying alleles both with A in FCGR2 A and TT in FCGR3A presented a trend of longer PFS(median 9 vs 5 mo;P=0.064). Chemotherapy impacted both iN KT cells and ADCC activity. Their prognostic values get lost when we analysed them after 2 and 4 mo of treatment.CONCLUSION: Our results suggest a link between iN KT cells,basal ADCC activity,genotypes in FCGR2A and FCGR3A,and efficacy of cetuximab in KRAS wt mC RC patients.
文摘In this paper, we introduce tail dependene measures for collateral losses from catastrophic events. To calculate these measures, we use bivariate compound process where a Cox process with shot noise intensity is used to count collateral losses. A homogeneous Poisson process is also examined as its counterpart for the case where the catastrophic loss frequency rate is deterministic. Joint Laplace transform of the distribution of the aggregate collateral losses is derived and joint Fast Fourier transform is used to obtain the joint distributions of aggregate collateral losses. For numerical illustrations, a member of Farlie-Gumbel-Morgenstern copula with exponential margins is used. The figures of the joint distributions of collateral losses, their contours and numerical calculations of risk measures are also provided.
基金the Science,Research and Innovation Promotion Funding(TSRI)(Grant No.FRB660012/0168)managed under Rajamangala University of Technology Thanyaburi(FRB66E0646O.4).
文摘This study presents the design of a modified attributed control chart based on a double sampling(DS)np chart applied in combination with generalized multiple dependent state(GMDS)sampling to monitor the mean life of the product based on the time truncated life test employing theWeibull distribution.The control chart developed supports the examination of the mean lifespan variation for a particular product in the process of manufacturing.Three control limit levels are used:the warning control limit,inner control limit,and outer control limit.Together,they enhance the capability for variation detection.A genetic algorithm can be used for optimization during the in-control process,whereby the optimal parameters can be established for the proposed control chart.The control chart performance is assessed using the average run length,while the influence of the model parameters upon the control chart solution is assessed via sensitivity analysis based on an orthogonal experimental design withmultiple linear regression.A comparative study was conducted based on the out-of-control average run length,in which the developed control chart offered greater sensitivity in the detection of process shifts while making use of smaller samples on average than is the case for existing control charts.Finally,to exhibit the utility of the developed control chart,this paper presents its application using simulated data with parameters drawn from the real set of data.
文摘Due to greedy algorithm is adopted in the analysis of dependency parsing based on transformation, thus we select the most likely analysis action in each analysis step and ignore the dependency relation analysis of sentences. Therefore, in this paper, we propose decision based multi-candidate Chinese dependency syntax method on the basis of traditional Are-eager algorithms proposed by Nivre. In the new method, multiple candidate structures are introduced. We select multiple possible motion analysis according to every analysis step, and the optimal solution is selected in the sentence, in order to determine the dependency relation between different words and improve the correct rate. We choose the Chinese Pennsylvania Treebank and establish dependency analyzer based on support vector machine, we prove the effectiveness of the algorithm.
基金supported by the National Natural Science Foundation of China(61503014,62073009)。
文摘Degradation and overstress failures occur in many electronic systems in which the operation load and environmental conditions are complex.The dependency of them called dependent competing failure process(DCFP),has been widely studied.Electronic system may experience mutual effects of degradation and shocks,they are considered to be interdependent.Both the degradation and the shock processes will decrease the limit of system and cause cumulative effect.Finally,the competition of hard and soft failure will cause the system failure.Based on the failure mechanism accumulation theory,this paper constructs the shock-degradation acceleration and the threshold descent model,and a system reliability model established by using these two models.The mutually DCFP effect of electronic system interaction has been decomposed into physical correlation of failure,including acceleration,accumulation and competition.As a case,a reliability of electronic system in aeronautical system has been analyzed with the proposed method.The method proposed is based on failure physical evaluation,and could provide important reference for quantitative evaluation and design improvement of the newly designed system in case of data deficiency.