A digraph is a graph in which each edge has an orientation. A linear directed path, , is a path whose all edges have the same orientation. A linear simple graph is called directed cordial if it admits 0 - 1 labeling t...A digraph is a graph in which each edge has an orientation. A linear directed path, , is a path whose all edges have the same orientation. A linear simple graph is called directed cordial if it admits 0 - 1 labeling that satisfies certain condition. In this paper, we study the cordiality of directed paths??and their second power . Similar studies are done for ?and the join ?. We show that ,? and ?are directed cordial. Sufficient conditions are given to the join?? to be directed cordial.展开更多
In this paper we have studied the effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning vertical electric field and azimuthal magnetic field at different distances, by using two...In this paper we have studied the effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning vertical electric field and azimuthal magnetic field at different distances, by using two-dimensional finite-difference time-domain (2-D FDTD) method in cylindrical coordinate systems. In order to analyze the electrostatic shielding effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning, we chose three mountains, and the left one is stroke by lightning, and the right one is near the obervation site, and the middle one with the top heights increasing from 0 to 2 km is between them. For the observed point, the electrostatic shielding effect of the right one on the lightning vertical electric field is the most serious, and the electric field is much less than that for strike to flat ground level;compared with the electric field, the shielding effect of the right one on the lightning azimuthal magnetic field becomes less, for most cases, the lightning magnetic field at the observed site is larger than that for flat ground cases mainly due to that of the increment caused by strike to the right mountain. With the increase of distance (e.g., 20 km from the lightning strike point), the shielding effect of the right mountain on the lightning field becomes less, because the reflected wave from the right mountain bottom plays a more important role over intermediate ranges, and the far radiation electromagnetic field peak value becomes larger due to such a reflecting wave. Therefore, in the lightning detecting technique, we should pay more attention to the effect caused by chains of hills on the lightning location and the estimation of lightning current peak.展开更多
The Drovers’ Paths are remnants of important land access roads from Rio Grande do Sul to São Paulo at the time of Colonial Brazil. They were built and used between the 18th and 20th centuries, particularly i...The Drovers’ Paths are remnants of important land access roads from Rio Grande do Sul to São Paulo at the time of Colonial Brazil. They were built and used between the 18th and 20th centuries, particularly in the region of Coxilha Rica. The main objective of this research is to develop a method for decision-making applied to the territorial landscape management in the Coxilha Rica. The method consisted of generating criteria to map the visibility spot reached from the main selected points;define the human visual acuity, realize bibliographic research, use cartographic and historical documents, inter-views, as well as field surveys that enabled the identification, characterization and mapping of historical farms and drovers’ paths. After data processing, the information was entered into the cartographic database;the data were cross-checked and analysis was made of the visibility of the surrounding farms and stone-walled corridors. Quality assessments showed that, with the visibility polygons, and through the use of cartographic tools, we could cross-check between different levels of information and analyze landscape intervention alternatives in order to minimize environmental impacts. When applying the method in the Coxilha Rica it was possible mapping the visibility polygon, taking human visual acuity into consideration, based on historical farms and stone-walled corridors;and making spatial analyses to explore alternatives to intervention (installation of power transmission systems) in order to preserve the scenic environment of the region. In the end, the decision was by does not construct the system.展开更多
Pathfinding is a kind of problem widely used in daily life. It is widely used in network games, map navigation and other fields. However, the traditional A* algorithm has some shortcomings, such as heuristic function ...Pathfinding is a kind of problem widely used in daily life. It is widely used in network games, map navigation and other fields. However, the traditional A* algorithm has some shortcomings, such as heuristic function needs to be designed according to different problems, path has many inflection points, and algorithm stability is poor. B* algorithm also has the shortcoming of inaccurate pathfinding. In order to solve the problems existing in A* and B* algorithms, obstacle avoidance regeneration mechanism, pre-exploration mechanism and equivalent waiting strategy are proposed. It adds a bidirectional parallel search mechanism to form an IBP-B* algorithm (Intelligent bi-directional parallel B* routing algorithm). The simulation results show that the speed of IBP-B* algorithm is 182% higher than that of A* algorithm and 366% higher than that of BFS algorithm. Meanwhile, compared with B* algorithm, IBP-B* algorithm improves the pathfinding accuracy of the algorithm.展开更多
In the game, we generally use A* algorithm for pathfinding according to the target location and map information to realize the tracking and interception task. This approach is simple to implement, but is often less th...In the game, we generally use A* algorithm for pathfinding according to the target location and map information to realize the tracking and interception task. This approach is simple to implement, but is often less than ideal in its presentation, because it does not allow game units to predictably choose paths based on dynamic targets or obstacles, and may lead to blocked channels or difficulty in choosing the actual optimal path. This paper focuses on analyzing the need of a unit when intercepting another unit in the game, and make an interception scheme which can adapt itself to dynamic obstacles and moving target thus presents artificial intelligence to some extent.展开更多
<strong>Objective:</strong> To understand the influencing factors of job burnout among nurses in Haikou 3A hospital and explore its direct and indirect effects, so as to provide a scientific basis for the ...<strong>Objective:</strong> To understand the influencing factors of job burnout among nurses in Haikou 3A hospital and explore its direct and indirect effects, so as to provide a scientific basis for the work efficiency of nursing staff. <strong>Methods:</strong> Between November 2, 2015 and November 2015, using multi stage random sampling, self-administered questionnaire survey was conducted among 1049 nursing staff, using the path analysis method to study the effect of direct and indirect factors effect. <strong>Results:</strong> The total score of job burnout of nurses was 38.44 ± 7.55, high occupational burnout was 0.9%, moderate occupational burnout was 66.5%, and low occupational burnout was 32.6%. The scores of job burnout were compared among the nurses with different titles, and less achievement (F = 8.342, P < 0.001) and depersonalization (F = 3.12, P = 0.025) were statistically significant. Nurses’ Job Burnout and job stressors were the first, and the canonical correlation coefficient was 0.4397 (F = 20.54, P < 0.0001), indicating that the more problems existed in patient care, the greater the degree of emotional exhaustion. The first canonical correlation coefficient of job burnout and job satisfaction of nurses was 0.3791 (F = 12.8, P < 0.0001), indicating that the better the family and work balance, the less individualized nurses were. The path analysis results showed that the 4 dimensions of job stressors (management and interpersonal problems) is positive, the direct effect of the strongest (0.219), the total effect of sort of work pressure source of 4 dimensions (0.245) > 5 dimensions of work pressure source (0.125) > title (<span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.112) job satisfaction scores (<span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.097). <strong>Conclusion:</strong> Job stress, job satisfaction and job title are the factors that affect job burnout. The 4 and the direct and indirect effects of展开更多
The major difficulty for the Feynman Path Integral Monte Carlo (PIMC) simulations of the quantum systems of particles is the so called “sign problem”, arising due to the fast oscillations of the path integral integr...The major difficulty for the Feynman Path Integral Monte Carlo (PIMC) simulations of the quantum systems of particles is the so called “sign problem”, arising due to the fast oscillations of the path integral integrand depending on the complex-valued action. Our aim is to find universal techniques being able to solve this problem. The new method combines the basic ideas of the Metropolis and Hasting algorithms and is based on the Picard-Lefschetz theory and complex-valued version of Morse theory. The basic idea is to choose the Lefschetz thimbles as manifolds approaching the saddle point of the integrand. On this thimble the imaginary part of the complex-valued action remains constant. As a result the integrand on each thimble does not oscillate, so the “sign problem” disappears and the integral can be calculated much more effectively. The developed approach allows also finding saddle points in the complexified space of path integral integration. Some simple test calculations and comparisons with available analytical results have been carried out.展开更多
Let G be a finite connected simple graph with vertex set V(G) and edge set E(G). A function f:V(G) → {1,1} is a signed dominating function if for every vertex v∈V(G), the closed neighborhood of v contains more verti...Let G be a finite connected simple graph with vertex set V(G) and edge set E(G). A function f:V(G) → {1,1} is a signed dominating function if for every vertex v∈V(G), the closed neighborhood of v contains more vertices with function values 1 than with −1. The signed domination number γs(G) of G is the minimum weight of a signed dominating function on G. In this paper, we calculate The signed domination numbers of the Cartesian product of two paths Pm and Pn for m = 3, 4, 5 and arbitrary n.展开更多
One of the principal difficulties related to road safety management in Brazil is the lack of data on road projects, especially those on rural roads, which makes it difficult to use road safety studies and models from ...One of the principal difficulties related to road safety management in Brazil is the lack of data on road projects, especially those on rural roads, which makes it difficult to use road safety studies and models from other countries as a reference. Updating road networks through the use of hyperspectral remote sensing images can be a good alternative. However, accurately recognizing and extracting hyperspectral images from roads has been recognized as a challenging task in the processing of hyperspectral data. In order to solve the aforementioned challenges, Hyperion hyperspectral images were combined with the Optimum Forest Path (OPF) algorithm for supervised classification of rural roads and the effectiveness of the OPF and SVM classifiers when applied to these areas was compared. Both classifiers produced reasonable results, however, the OPF algorithm outperformed SVM. The higher classification accuracy obtained by the OPF was mainly attributed to the ability to better distinguish between regions of exposed soil and unpaved roads.展开更多
In order to enhance the Pd based anodic catalysts for direct formic acid fuel cells (DFAFCs), the research work includes increasing catalyst activity and preventing CO poison. In this study, various zirconium oxides-m...In order to enhance the Pd based anodic catalysts for direct formic acid fuel cells (DFAFCs), the research work includes increasing catalyst activity and preventing CO poison. In this study, various zirconium oxides-modified multi-walled carbon nanotubes (MWCNTs) were prepared as the supports of Pd catalysts for DFAFCs by adjusting the preparation parameters: metal adding, sintering temperature and atmospheres. The prepared pure zirconia has both monoclinic and tetragonal phases. The addition of MWCNTs depresses the growth of monoclinic phase. A small amount of Pd adding allows both monoclinic and tetragonal zirconia structures to appear again. Pd nanoparticles of 20 wt% synthesized on MWCNTs and tetragonal ZrO2/MWCNTs have similar particle size, while Pd/[Pd:ZrO2/AO-MWCNTs-300Air-900Ar] have more nanoparticles aggregation. The electrochemical surface area can be improved by adding zirconia which implies those zirconia modified Pd catalysts better electrocatalytic performance. By analyzing the maximum current density and the corresponding potential, Pd/AO-MWCNTs are inferred to undergo the formic acid direct oxidation initially. The Pd catalysts modified by tetragonal ZrO2 have higher current density. Those having both tetragonal and monoclinic ZrO2 modified Pd catalysts have lower potential of formic acid oxidation. All the Pd based catalysts with zirconia modification possess better CO resist ability and electrocatalytic activity. Pd/[ZrO2/AO-MWCNTs-300Air-900Ar] and Pd/[Pd:ZrO2/AO-MWCNTs-300Air-900Ar] which catalyze formic acid in direct oxidation path are the two best catalysts.展开更多
文摘A digraph is a graph in which each edge has an orientation. A linear directed path, , is a path whose all edges have the same orientation. A linear simple graph is called directed cordial if it admits 0 - 1 labeling that satisfies certain condition. In this paper, we study the cordiality of directed paths??and their second power . Similar studies are done for ?and the join ?. We show that ,? and ?are directed cordial. Sufficient conditions are given to the join?? to be directed cordial.
文摘In this paper we have studied the effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning vertical electric field and azimuthal magnetic field at different distances, by using two-dimensional finite-difference time-domain (2-D FDTD) method in cylindrical coordinate systems. In order to analyze the electrostatic shielding effect of strike to a cone-shaped mountain surrounded by two chains of hills on the lightning, we chose three mountains, and the left one is stroke by lightning, and the right one is near the obervation site, and the middle one with the top heights increasing from 0 to 2 km is between them. For the observed point, the electrostatic shielding effect of the right one on the lightning vertical electric field is the most serious, and the electric field is much less than that for strike to flat ground level;compared with the electric field, the shielding effect of the right one on the lightning azimuthal magnetic field becomes less, for most cases, the lightning magnetic field at the observed site is larger than that for flat ground cases mainly due to that of the increment caused by strike to the right mountain. With the increase of distance (e.g., 20 km from the lightning strike point), the shielding effect of the right mountain on the lightning field becomes less, because the reflected wave from the right mountain bottom plays a more important role over intermediate ranges, and the far radiation electromagnetic field peak value becomes larger due to such a reflecting wave. Therefore, in the lightning detecting technique, we should pay more attention to the effect caused by chains of hills on the lightning location and the estimation of lightning current peak.
文摘The Drovers’ Paths are remnants of important land access roads from Rio Grande do Sul to São Paulo at the time of Colonial Brazil. They were built and used between the 18th and 20th centuries, particularly in the region of Coxilha Rica. The main objective of this research is to develop a method for decision-making applied to the territorial landscape management in the Coxilha Rica. The method consisted of generating criteria to map the visibility spot reached from the main selected points;define the human visual acuity, realize bibliographic research, use cartographic and historical documents, inter-views, as well as field surveys that enabled the identification, characterization and mapping of historical farms and drovers’ paths. After data processing, the information was entered into the cartographic database;the data were cross-checked and analysis was made of the visibility of the surrounding farms and stone-walled corridors. Quality assessments showed that, with the visibility polygons, and through the use of cartographic tools, we could cross-check between different levels of information and analyze landscape intervention alternatives in order to minimize environmental impacts. When applying the method in the Coxilha Rica it was possible mapping the visibility polygon, taking human visual acuity into consideration, based on historical farms and stone-walled corridors;and making spatial analyses to explore alternatives to intervention (installation of power transmission systems) in order to preserve the scenic environment of the region. In the end, the decision was by does not construct the system.
文摘Pathfinding is a kind of problem widely used in daily life. It is widely used in network games, map navigation and other fields. However, the traditional A* algorithm has some shortcomings, such as heuristic function needs to be designed according to different problems, path has many inflection points, and algorithm stability is poor. B* algorithm also has the shortcoming of inaccurate pathfinding. In order to solve the problems existing in A* and B* algorithms, obstacle avoidance regeneration mechanism, pre-exploration mechanism and equivalent waiting strategy are proposed. It adds a bidirectional parallel search mechanism to form an IBP-B* algorithm (Intelligent bi-directional parallel B* routing algorithm). The simulation results show that the speed of IBP-B* algorithm is 182% higher than that of A* algorithm and 366% higher than that of BFS algorithm. Meanwhile, compared with B* algorithm, IBP-B* algorithm improves the pathfinding accuracy of the algorithm.
文摘In the game, we generally use A* algorithm for pathfinding according to the target location and map information to realize the tracking and interception task. This approach is simple to implement, but is often less than ideal in its presentation, because it does not allow game units to predictably choose paths based on dynamic targets or obstacles, and may lead to blocked channels or difficulty in choosing the actual optimal path. This paper focuses on analyzing the need of a unit when intercepting another unit in the game, and make an interception scheme which can adapt itself to dynamic obstacles and moving target thus presents artificial intelligence to some extent.
文摘<strong>Objective:</strong> To understand the influencing factors of job burnout among nurses in Haikou 3A hospital and explore its direct and indirect effects, so as to provide a scientific basis for the work efficiency of nursing staff. <strong>Methods:</strong> Between November 2, 2015 and November 2015, using multi stage random sampling, self-administered questionnaire survey was conducted among 1049 nursing staff, using the path analysis method to study the effect of direct and indirect factors effect. <strong>Results:</strong> The total score of job burnout of nurses was 38.44 ± 7.55, high occupational burnout was 0.9%, moderate occupational burnout was 66.5%, and low occupational burnout was 32.6%. The scores of job burnout were compared among the nurses with different titles, and less achievement (F = 8.342, P < 0.001) and depersonalization (F = 3.12, P = 0.025) were statistically significant. Nurses’ Job Burnout and job stressors were the first, and the canonical correlation coefficient was 0.4397 (F = 20.54, P < 0.0001), indicating that the more problems existed in patient care, the greater the degree of emotional exhaustion. The first canonical correlation coefficient of job burnout and job satisfaction of nurses was 0.3791 (F = 12.8, P < 0.0001), indicating that the better the family and work balance, the less individualized nurses were. The path analysis results showed that the 4 dimensions of job stressors (management and interpersonal problems) is positive, the direct effect of the strongest (0.219), the total effect of sort of work pressure source of 4 dimensions (0.245) > 5 dimensions of work pressure source (0.125) > title (<span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.112) job satisfaction scores (<span style="white-space:nowrap;"><span style="white-space:nowrap;">−</span></span>0.097). <strong>Conclusion:</strong> Job stress, job satisfaction and job title are the factors that affect job burnout. The 4 and the direct and indirect effects of
文摘The major difficulty for the Feynman Path Integral Monte Carlo (PIMC) simulations of the quantum systems of particles is the so called “sign problem”, arising due to the fast oscillations of the path integral integrand depending on the complex-valued action. Our aim is to find universal techniques being able to solve this problem. The new method combines the basic ideas of the Metropolis and Hasting algorithms and is based on the Picard-Lefschetz theory and complex-valued version of Morse theory. The basic idea is to choose the Lefschetz thimbles as manifolds approaching the saddle point of the integrand. On this thimble the imaginary part of the complex-valued action remains constant. As a result the integrand on each thimble does not oscillate, so the “sign problem” disappears and the integral can be calculated much more effectively. The developed approach allows also finding saddle points in the complexified space of path integral integration. Some simple test calculations and comparisons with available analytical results have been carried out.
文摘Let G be a finite connected simple graph with vertex set V(G) and edge set E(G). A function f:V(G) → {1,1} is a signed dominating function if for every vertex v∈V(G), the closed neighborhood of v contains more vertices with function values 1 than with −1. The signed domination number γs(G) of G is the minimum weight of a signed dominating function on G. In this paper, we calculate The signed domination numbers of the Cartesian product of two paths Pm and Pn for m = 3, 4, 5 and arbitrary n.
文摘One of the principal difficulties related to road safety management in Brazil is the lack of data on road projects, especially those on rural roads, which makes it difficult to use road safety studies and models from other countries as a reference. Updating road networks through the use of hyperspectral remote sensing images can be a good alternative. However, accurately recognizing and extracting hyperspectral images from roads has been recognized as a challenging task in the processing of hyperspectral data. In order to solve the aforementioned challenges, Hyperion hyperspectral images were combined with the Optimum Forest Path (OPF) algorithm for supervised classification of rural roads and the effectiveness of the OPF and SVM classifiers when applied to these areas was compared. Both classifiers produced reasonable results, however, the OPF algorithm outperformed SVM. The higher classification accuracy obtained by the OPF was mainly attributed to the ability to better distinguish between regions of exposed soil and unpaved roads.
文摘In order to enhance the Pd based anodic catalysts for direct formic acid fuel cells (DFAFCs), the research work includes increasing catalyst activity and preventing CO poison. In this study, various zirconium oxides-modified multi-walled carbon nanotubes (MWCNTs) were prepared as the supports of Pd catalysts for DFAFCs by adjusting the preparation parameters: metal adding, sintering temperature and atmospheres. The prepared pure zirconia has both monoclinic and tetragonal phases. The addition of MWCNTs depresses the growth of monoclinic phase. A small amount of Pd adding allows both monoclinic and tetragonal zirconia structures to appear again. Pd nanoparticles of 20 wt% synthesized on MWCNTs and tetragonal ZrO2/MWCNTs have similar particle size, while Pd/[Pd:ZrO2/AO-MWCNTs-300Air-900Ar] have more nanoparticles aggregation. The electrochemical surface area can be improved by adding zirconia which implies those zirconia modified Pd catalysts better electrocatalytic performance. By analyzing the maximum current density and the corresponding potential, Pd/AO-MWCNTs are inferred to undergo the formic acid direct oxidation initially. The Pd catalysts modified by tetragonal ZrO2 have higher current density. Those having both tetragonal and monoclinic ZrO2 modified Pd catalysts have lower potential of formic acid oxidation. All the Pd based catalysts with zirconia modification possess better CO resist ability and electrocatalytic activity. Pd/[ZrO2/AO-MWCNTs-300Air-900Ar] and Pd/[Pd:ZrO2/AO-MWCNTs-300Air-900Ar] which catalyze formic acid in direct oxidation path are the two best catalysts.