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    30 April 2020, Volume 41 Issue 2 Previous Issue    Next Issue

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    Realistic modeling and rendering of hydraulic erosion terrain
    ZHENG Gu-ping1, ZHANG Meng1, SHAO Xu-qiang1, WU Zhao-hui2
    2020, 41(2): 169-177.  DOI: 10.11996/JG.j.2095-302X.2020020169
    Abstract ( 251 )   PDF (4485KB) ( 352 )  
    Hydraulic erosion topography is a common natural phenomenon in both real life and virtual scenes. In order to study the surface erosion by hydraulic power, a realistic simulation model is proposed by applying the smoothed particle hydrodynamics (SPH) to simulate the wetting and erosion process of the surface affected by fluid. Based on the reasonable simplified description of the real splash erosion in nature, a three stages topographic hydraulic splash erosion model is proposed. Firstly, the effect of water flow on the surface is simulated by the deformation model of projectile impacting flat target. Secondly, the calculation method of water permeability based on Darcy’s law is used to ensure the authenticity of surface water absorption and water diffusion. Finally, a new calculation model is proposed, which takes into account the influence of surface moisture on surface erosion. The experimental results show that the model can simulate the erosion effects of water flow in different directions on surface and the phenomena of surface water absorption and moisture diffusion during the erosion process.
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    DPC: multi-perspective evaluation framework based on  augmented reality children’s picture books
    HOU Wen-jun1,2, TANG Li-xing1,2
    2020, 41(2): 178-186.  DOI: 10.11996/JG.j.2095-302X.2020020178
    Abstract ( 173 )   PDF (3175KB) ( 170 )  
    Augmented reality (AR) technology, as a bridge between reality and virtual scene, can stimulate users’ imagination, sense of space and creativity. In view of the problems with the existing AR children’s picture books such as inadequate integration of virtual and reality, and homogeneity in the form of games and type of interaction, this study intends to create AR children’s picture book games capable of teaching through lively activities. Firstly, 59 mobile augmented reality applications were studied and classified. The method of Delphi was used to select some suitable game types which were then transferred to children’s picture books. Next, children aged 6 to 12 (n=6) were asked to try out our applications. At the same time, we observed what they did and interviewed them. A focus group made up of parents/teachers (n=7) and our developers (n=5) discussed the picture books and applications. Finally, the needs and corresponding indicators for AR children’s picture books were extracted from developers, parents/teachers and children. The framework DPC (developer, parents/teachers, children) on the three dimensions was obtained, each of which was further segmented. We adopted the framework DPC to improve our AR children’s picture book games.
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    Surveillance video analysis system based on SpiralTape summarization
    JIANG Hong-tao1, CHEN Xiao-hua1, SHI Yue2,3, MA Cui-xia2,3
    2020, 41(2): 187-195.  DOI: 10.11996/JG.j.2095-302X.2020020187
    Abstract ( 88 )   PDF (11979KB) ( 204 )  
    Surveillance video is an important part of security systems. In today’s all walks of life, surveillance video is inseparable when it comes to security. However, the video content is still analyzed largely manually, which costs much manpower and time. With the increasing amount of surveillance video data, it is important to figure out how to improve the analysis efficiency of surveillance video content and reduce user’s cognitive load in order to make higher use of the videos. Aiming at the problems of redundant information in surveillance video and inefficient manual acquisition of key video content, a visual analysis system for surveillance video content was developed by applying SpiralTape summarization and corresponding interactive technologies. Combined with the detection data of moving objects, the object statistical information of visual videos was obtained from multiple angles based on the display advantages of the SpiralTape summarization. Finally, fast and efficient access to surveillance video content was achieved with auxiliary methods such as navigation, positioning and sketch interaction for the SpiralTape summarization.
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    Batik dyeing simulation based on convolutional neural network
    LI Zhi, XU Dan
    2020, 41(2): 196-203.  DOI: 10.11996/JG.j.2095-302X.2020020196
    Abstract ( 89 )   PDF (8877KB) ( 152 )  
    Batik, a traditional art of the Chinese ethnic minority, is widely popular in southwest China. The Batik simulation mainly includes two major tasks: crack simulation and fabric dyeing simulation. In this paper, we mainly focus on fabric dyeing simulation. Previously, the method of Batik dyeing simulation can only perform monochromatic dyeing, and the simulation effect of self-dyeing is not obvious. Thus, a multicolor batik dyeing method based on convolutional neural network is proposed. To begin with, the crack was generated by the method based on distance transformation and then the shape of the crack is modified. Furthermore, we used Label me to segment the specific areas of the image manually, which facilitated the subsequent coloring. Finally, the PhotoWCT algorithm was applied to dye the specific regions of the image, and then the pixel affinities in the content map were used to smooth the dyed result. In this way, the result obtained is closer to the real Batik image. The experimental results indicate that, the method proposed in this article is applicable to multicolor dyeing simulation. In addition, this method is superior to the previous method in terms of sfumato effect.
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    Research on experience design of interactive public guidance system  based on SEM
    HU Shan1, JIANG Xu1, FU Kai-jie1, ZHOU Ming-yu1, LUO Yi-ming2, QIAO Zhong-lin3
    2020, 41(2): 204-209.  DOI: 10.11996/JG.j.2095-302X.2020020204
    Abstract ( 104 )   PDF (1297KB) ( 270 )  
    In order to increase user’s satisfaction with the interactive guidance system and help designers to accurately obtain users’ needs, the structural equation model (SEM) is introduced into the interactive guidance system, and the elements of user experience of the interactive public guidance system are divided into four latent variables. Then, through expert interview, the observable variables affecting the user experience (UE) satisfaction of each of the four latent variables are analyzed and the SEM questionnaire is established. Next, through questionnaire survey and data analysis, the SEM of the user satisfaction of the interactive public guidance system is established. And the impact weights of the four latent variables and their observable variables are obtained. Finally, taking the campus interactive public guidance system as an example, the function, shape and user interface are improved to improve the UE based on the above user satisfaction SEM. This method is compared, with the assistance of PSSUQ, with the existing interactive public guidance system to verify the feasibility of the design and then provide theoretical implications for further research on the experience design of the interactive public guidance system.
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    Personalized dialogue content generation based on deep learning
    WANG Hao, GUO Bin, HAO Shao-yang, ZHANG Qiu-yun, YU Zhi-wen
    2020, 41(2): 210-216.  DOI: 10.11996/JG.j.2095-302X.2020020210
    Abstract ( 195 )   PDF (402KB) ( 248 )  
    Dialogue system is a very important research direction in the field of Human–Machine Interaction and the research of open domain chatbot has attracted much attention. There are three main problems in the existing chatbots. The first is that they cannot effectively capture the context, which leads to the lack of logical cohesion in the dialogue content. Second, most of the existing chatbots do not have specific personalized characteristics, resulting in the monotony in the chat process, and the dialogue content may be contradictory. Third, they tend to generate meaningless replies such as “I don’t know” or “I’m sorry”, which greatly reduces users’ interest in chat. The Encoder-Decoder framework based on Transformer was used to build the general dialogue model and personalized dialogue model. By encoding the historical dialogue content and personalized feature information, the model could effectively capture the context and the personalized information and realize multi-round dialogue process, generating personalized dialogue content. The experimental results showed that the dialogue model based on Transformer obtained better results on the evaluation metrics of perplexity and F1-score compared to the baseline models. Combined with manual evaluation, it is concluded that our dialogue model is capable of carrying out multi-round dialogues, with high content diversity and in line with the given personalized characteristics.
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    Design of virtual reality simulated driving teaching system based on BCI
    TENG Jian, HUANG Jia-hui, GONG Kai
    2020, 41(2): 217-223.  DOI: 10.11996/JG.j.2095-302X.2020020217
    Abstract ( 111 )   PDF (3504KB) ( 135 )  
    In the traditional simulated driving, the training of normal scenes has received too much attention, the monitoring and assistance of the trainees’ psychological state in the accident scenes has been overlooked, and the driving psychological state has obtained no feedback and evaluation. In order to solve these problems, based on brain-computer interaction (BCI) and virtual reality (VR), a virtual reality simulated driving teaching demonstration system was developed. The simulated driving operating system was developed by using three-dimensional dynamics engine. And the wearable electroencephalogram (EEG) signal detection helmet was designed on hardware. The monitoring and data evaluation of the trainees’ brain state during simulated driving was realized based on BCI technology. When a sudden simulated event occurs, the system will automatically brake or assist driving through brain-computer interface technology. After completing the simulated driving training, emergency rescue measures can be given according to EEG feedback in the accident. In addition the students’ performance and psychological quality can be assessed based on EEG. The method proposed in this article provides a richer and more immersive interactive operation mode for the teaching and training with higher cognitive load, such as virtual driving, and improves the practicality and usability of the teaching and training system in this field.
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    Design and implementation of a multi-scale summarization for  unmanned aerial vehicle videos
    YANG Da-shen1, CHEN Ke-qi2,3, MA Cui-xia2,3
    2020, 41(2): 224-232.  DOI: 10.11996/JG.j.2095-302X.2020020224
    Abstract ( 85 )   PDF (1407KB) ( 119 )  
    Unmanned aerial vehicle (UAV) videos, an important video resources captured by unmanned aerial vehicles, are now being widely used in ground target monitoring. However, there’s usually a large amount of space-time redundancy in UAV videos due to their grand view and unspecified targets, making the traditional methods of video interaction inefficient to get usable details. To solve the problem, a multi-scale spiral summarization for UAV videos was proposed. Firstly, we trained a detection model based on YOLOv3 algorithm to detect the small targets including pedestrians and vehicles from the UAV’s perspective. Then, we proposed a key-frame-based video object detection algorithm, by first extracting the key frames of the videos according to the improved color-feature-based key-frame-extraction algorithm, and then applying the model on the key frames to get the target detection results of the whole video. The key areas from the key frames were extracted as the displaying units of video summarization in a spiral form from the inside out with basic functions including key-frame-based video location and dynamic scaling. At last, some novel extended interaction tools were developed including sketch annotation, object distribution spiral and double spiral player, aiming to meet the users’ potential needs, and help them interact with the UAV videos more efficiently.
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    Development and application of virtual reality software for the practical teaching of sewage treatment plant
    QIU Yuan-hang1, SUN Xian-bo1, LIU Yong-di1, CAI Zheng-qing1, XU Hong-yong2
    2020, 41(2): 233-236.  DOI: 10.11996/JG.j.2095-302X.2020020233
    Abstract ( 98 )   PDF (2565KB) ( 134 )  
    Currently, the practical teaching cannot meet the goal of talent training because students lack the opportunity to operate the equipment and observe the details of the project in the field trip of sewage treatment plant. To solve this problem, a complete set of VR-based teaching software for sewage treatment plant was developed by means of the UE4 and C4D. This software contains one virtual experiment center and 13 cases of sewage treatment structures. Students are able to experience the complete process of sewage treatment, as well as master the principle of sewage treatment, the structure construction and the equipment layout. What’s more, students can operate engineering equipment, and control the main process parameters in the software. Through the online and classroom teaching, VR practical teaching and assessment feedback, students can understand the sewage treatment plant comprehensively. The teaching software of sewage treatment plant based on virtual reality is complementary to traditional teaching, which provides a solution to the problem of the poor practical teaching of environmental engineering. As survey results show, the VR teaching software achieves the goal of environmental engineering practical teaching.
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    Load balancing algorithm based on greedy strategy for multi-node  parallel ray tracing
    LIU Yun-biao, CHEN Chun-yi, HU Xiao-juan, XING Qi-wei, YANG Hua-min
    2020, 41(2): 237-245.  DOI: 10.11996/JG.j.2095-302X.2020020237
    Abstract ( 77 )   PDF (4700KB) ( 122 )  
    A load-balancing algorithm based on greedy strategy for multi-node parallel ray tracing was proposed to improve the parallelism degree of applying ray tracing cluster to producing high-definition pictures of complex scenes. Firstly, according to parallel property of GPU, the screen space was divided into a number of square image blocks. Based on the projection of the spherical bounding box of moving objects on the screen, the binary rendering time influence map was constructed. Then on the basis of the spatiotemporal correlation, the rendering task queue was established by combining the time consumed by the previous image block and the binary rendering time influence map. Then the dynamic allocation of multi-rendering node tasks was realized through two-step load-balancing. Finally, the method was verified and analyzed based on experimental data. The results showed that this method presents good load-balancing effect, and the rendering efficiency can be improved by up to 4.96 times.
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    Anderson acceleration for B-spline curve fitting
    QIN Wen-jie, ZHANG Ju-yong
    2020, 41(2): 246-254.  DOI: 10.11996/JG.j.2095-302X.2020020246
    Abstract ( 263 )   PDF (1339KB) ( 135 )  
    In recent years, curve fitting technology has been widely used in image processing, engineering experiments and other fields. Among them, B-spline curve fitting is the most common method in curve fitting, the method of B-spline curve fitting has the advantages of locality, continuity but the fitting precision is relatively low. In practical application, B-spline curve fitting requires higher accuracy and speed. In order to increase the speed of planar B-spline curve fitting, Anderson acceleration is applied to the method of planar B-spline curve fitting. And then a quasi-Newton method based on Anderson acceleration is proposed. Firstly, an initial shape is set, and then the position parameters of the projection point of each data point are found according to the initial shape. Then, the corresponding position of control points is calculated by Anderson acceleration, and the above two steps are iterated until the result converges. The experimental results show that the proposed method in this paper outperforms other methods with respect to convergence speed and iteration time.
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    Review on related studies of local binary descriptors
    BIAN Hou-qin1, ZHANG Hao-lin1, HUANG Fu-zhen2
    2020, 41(2): 254-261.  DOI: 10.11996/JG.j.2095-302X.2020020254
    Abstract ( 125 )   PDF (1969KB) ( 134 )  
    Local binary descriptor is an important research object in local invariant features, which is widely used in computer vision and pattern recognition. Recently, the local binary descriptors represented by BRIEF have been proposed one by one. In this paper, the research results and development of local binary descriptors in the past decade are reviewed and discussed in order to provide implications for related preliminary researchers and application engineers. Firstly, the typical modern local binary descriptors were summarized. Secondly, the methods of improving these descriptors were analyzed. Finally, the relevant experimental evaluation criteria were discussed, and the future research prospects were expounded in view of the existing problems at the present stage. As a whole, local binary descriptors have experienced remarkable development and progress in recent years, and many studies on local binary descriptors have achieved success in increasing descriptors’ universality, robustness and efficiency. Aiming at different application scenarios, some improved descriptors also have ability to deal with practical problems. Such advancement has laid a solid foundation and provided more implications for the further development of local binary descriptors characteristic of higher-level and multi-field expansion. Although the advancement of local binary descriptors marks the progress of computer vision technology, there are still some common problems and contradictions, which needs to be further studied d and solved by related researchers.
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    Super-resolution reconstruction of depth image guided by color image  based on CNN
    WANG Zi-wei1,2, DENG Hui-ping1,2, XIANG Sen1,2, YANG Jian-fan1,2
    2020, 41(2): 262-269.  DOI: 10.11996/JG.j.2095-302X.2020020262
    Abstract ( 226 )   PDF (2432KB) ( 298 )  
    The depth image indicates the relative distance between the objects in the three-dimensional scene. According to the information expressed by the depth image, the position of the object in space and the relative distance between different objects can be accurately obtained, so that the depth image has a wide range of applications in areas such as stereo vision. However, due to the limitations of RGB-D sensor hardware, the acquired resolution of depth image is low, which cannot meet the requirements of some practical applications with high precision. Deep learning, especially the convolutional neural networks (CNN), has achieved great success in image processing in recent years. In this light, this paper proposes a super-resolution reconstruction method of depth image guided by color image based on CNN. First, the CNN are used to obtain the edge feature information of color images and the depth feature information of depth images, so as to obtain high-resolution depth images with clear edge texture. Then, the edge texture details of the depth image are further optimized by the convolution layer of the filter kernels of different sizes, so as to obtain the depth image with higher resolution. The experimental results show that the RMSE value of the method proposed is lower than that of other methods, and the reconstructed image shows clearer edge texture details.
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    Indoor scene modeling method based on template replacement
    ZHANG Zhao-xuan1, WANG Cheng-bin1, YANG Xin1, PIAO Xing-lin2, WANG Peng-jie3, YIN Bao-cai1
    2020, 41(2): 270-276.  DOI: 10.11996/JG.j.2095-302X.2020020270
    Abstract ( 70 )   PDF (1237KB) ( 108 )  

    Nowadays, much progress has been made in the research of indoor scene modeling, especially the modeling frameworks based on multiple perspectives and single perspective, which has enhanced the robot’s environment perception. However, the following shortcomings still exist: The modeling method based on multiple perspectives requires a long pre-processing time, and the offline optimization process is required after the modeling is completed, which cannot meet the modeling requirements under specific conditions. The modeling algorithm based on single perspective is mainly output with voxels, so the modeling quality is low, and the information is missing seriously. The details of the scene cannot be accurately characterised, and it is difficult to meet the requirements of robot interaction. In view of the above deficiencies, this paper puts forward a method of indoor scene modeling based on template replacement. First, the three-dimensional point cloud scene is preprocessed to segment a single object with missing point cloud, and then the virtual scanning technology is used to sample the surface points of the object and calculate the corresponding normal vector and curvature. Next, the octree mesh is used to store the normal vector and the curvature information respectively. Furthermore, the high-dimensional feature vectors are extracted by the convolutional neural network (CNN), and the Euclidean distance is compared with the features of three-dimensional object in the database, so as to obtain the retrieval sequence. Finally, the most similar objects are selected from the sequence, and the iterative closest point (ICP) registration method is used to register with the scanning scene to complete the scene optimization. In this paper, the proposed network model is tested on two benchmark data sets and shows good performance.

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    Human action recognition based on ResNeXt
    JIANG Sheng-nan, CHEN En-qing, ZHEN Ming-yao, DUAN Jian-kang
    2020, 41(2): 277-282.  DOI: 10.11996/JG.j.2095-302X.2020020277
    Abstract ( 174 )   PDF (2804KB) ( 172 )  
    Human action recognition is one of the core research directions in the field of computer vision and is applied in many occasions. Deep convolutional neural networks have achieved great success in static image recognition and have gradually expanded into the field of video content recognition, but they still face great challenges in applications. This paper proposes a deep neural network model based on ResNeXt network for human action recognition in video. The main innovations of this paper include: ① The new ResNeXt network structure was used to replace the original convolutional neural network structure. Two kinds of modal data of RGB and optical flow was collected to make full use of the appearance and temporal order information in the video. ② The end-to-end video time segmentation strategy was applied to the proposed ResNeXt network model. The video was divided into K segments to model the long-range time structure of the video sequence, and the optimal value of K was obtained through tests, which enables the model to better distinguish the similar actions with sub-action sharing phenomenon and solve the problems of misjudgment that are easy to emerge due to similar sub-actions. Tests performed on the widely used action recognition data sets UCF101 and HMDB51 showed that the action recognition accuracy of the proposed model and method is better than that of the models and methods in the existing literature.
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    Simulation study on the blocking effect of pig skin on spherical projectile
    TANG Cheng-li, LIU Su-su, YANG Yu-ping, FANG Jia-heng
    2020, 41(2): 283-287.  DOI: 10.11996/JG.j.2095-302X.2020020283
    Abstract ( 80 )   PDF (1239KB) ( 110 )  
    In order to clarify the blocking mechanism of skin on spherical bullet, a three-layer structural model of simulated skin was established. Based on the mechanical curves of tensile and compression experiments, the parameters of the skin model were identified by MATLAB. Based on the skin penetration threshold velocity obtained from the impact experiment, the accuracy of the skin model was verified. Then, the penetration process of Φ4.5 mm shot into the skin was simulated by LS-DYNA simulation, and the blocking effect of skin on spherical projectile was analyzed from the aspects of velocity attenuation and skin bulging. The penetration process of Φ4.5 mm projectile into the skin under the condition of the same kinetic energy and different density, together with the process of shot put into the skin with the same kinetic energy and different diameter, was numerically simulated. The results show that the three-layer structural model of skin can be taken as a numerical simulation model to simulate the real damage of skin. Furthermore, with the same initial kinetic energy, the smaller the density of spherical projectile is, the larger the volume is, the larger the energy dissipation ratio is, and the more obvious the skin blocking effect is. Such finding slay a foundation for the future study of the harm of the projectile to the real human body.
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    Simulation analysis on mechanical properties of aluminium cable steel reinforced under tensile load
    ZHOU Xin-kai1, QU Chang1, LIU Su-su1,2, YAO Jian-nan1, WANG Jing-jing3
    2020, 41(2): 288-294.  DOI: 10.11996/JG.j.2095-302X.2020020288
    Abstract ( 162 )   PDF (3178KB) ( 149 )  
     In order to study the influence of structural parameters of aluminium cable steel reinforced (ACSR) on its mechanical property under tensile load, a parametric finite element model of ACSR was established based on the ANSYS parametric design language (APDL). First, the stress distribution of TACSR/AS-410/70 and the variation law of its layered stress and strain with tensile loads were simulated and studied. And then the finite element model of TACSR/AS-410/70 was verified by the tensile experiment. Furthermore, the parametric finite element model was used to simulate the mechanical response of cables with different lay ratio or aluminum-steel ratio. It can be concluded from the simulation results that as aluminum-steel ratio increases, maximum equivalent stress between different layers of the ACSR increases more slowly with the increase of load, the maximum stress of the strand is lower, and the stress distribution between strands is more even. However, as the lay ratio of ACSR is smaller, the strand is tighter and stress of strands in different layers is larger. The experimental results provide significant implications for the design of ACSR’s structure and the selection and optimization design of cable clamp.
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    Construction method of error transfer graph of geometric elements
    YANG Ling-feng, WU Yu-guang
    2020, 41(2): 295-303.  DOI: 10.11996/JG.j.2095-302X.2020020295
    Abstract ( 56 )   PDF (731KB) ( 85 )  
    In view of the problems of inspection, analysis and management of annotation in 3D environment, the present study proposed the concept and construction method of error transfer relationship graph of part geometric elements based on solid models. First, the sub graph of error transfer relationship was established according to the datum-target relationship between geometric elements associated with geometric tolerance. Then, the datum-target relationship between geometric elements associated with dimension tolerance was determined according to the geometric elements’ types, location relationships and location information of dimension lines. Thus, the directionless dimension relationship between geometric elements was transformed into the directional error transfer relationship, increasing and expanding the error transfer relationship sub graph. Finally, the error transfer graph of the whole part was constructed. Based on the secondary development function of the software SolidWorks, the prototype software was developed with VC++, and the feasibility of the method was verified through exemplification.
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    Clustering of BIM components based on similarity measurement of attributes
    WANG Wan-qi1, MA Bao-rui2, LI Qian2, LU Wen-long1, LIU Yu-shen2
    2020, 41(2): 304-312.  DOI: 10.11996/JG.j.2095-302X.2020020304
    Abstract ( 129 )   PDF (962KB) ( 304 )  
    In recent years, resources in the Building Information Modeling (BIM) components library are expanding rapidly on the Internet. There is an increasing demand for ways to cluster and retrieve appropriate BIM components among countless resources. However, the way to extract domain information of BIM components still can not be found in existing methods. This paper studies the clustering of BIM components based on the domain information of BIM components: ①For BIM components, tan algorithm measuring similarity is proposed based on the attribute information. Compared with the traditional Tversky similarity measure algorithm and geometry similarity matching algorithm, the newly proposed one the present study has produced a better result. ②A clustering method of BIM component library is proposed based on the similarity measure algorithm of BIM components. Users are provided with diverse ways to retrieve and check information thanks to the search engine of BIMSeek integrated with functions of keyword-based retrieval and classifier view. Compared with the K-medoids algorithm and AP algorithm, the results of ours are more desirable.
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    Automatic extraction method of logic relationship of electromechanical  device based on graph theory
    XU Jing-lin, GAO Shang, YU Fang-qiang
    2020, 41(2): 313-318.  DOI: 10.11996/JG.j.2095-302X.2020020313
    Abstract ( 120 )   PDF (2529KB) ( 143 )  
     With the in-depth application of building information modeling (BIM) in the phrases of construction, operation and maintenance, the automatic extraction of logical relationship of building electromechanical devices has become a bottleneck for further application. This article proposes an automatic extraction method of logic relationship of electromechanical system based on graph theory. First, the electromechanical system was abstracted as a non-directional connected graph base on the BIM model, and the connector was abstracted as the edge of the graph. Then, the devices, pipelines and pipeline attachments were abstracted as the nodes of the graph. Next, a flat of pipelines were abstracted as a pipeline cluster so that the complex connection could be converted into a simple connection from the device to several pipe clusters. Finally, the problem of automatically generating the logical relationship was changed into the problem of solving the undirected connected graph. This article established a method of extracting the physical connection relationship of electromechanical components, automatically generating logical relations and calculating connection path of devices. In this way, the logical relations can be extracted fast, accurately and intelligently. In addition, the implementation of this method in engineering is beneficial to the operation and maintenance management of electromechanical system based on BIM.
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    Research and practice on teaching reform of civil engineering computer aided drawing
    YANG Wan-li, WANG Ning, WANG Guang-jun
    2020, 41(2): 319-324.  DOI: 10.11996/JG.j.2095-302X.2020020319
    Abstract ( 263 )   PDF (1188KB) ( 156 )  
    Based on the disadvantages of the teaching of civil engineering computer aided drawing (CAD) course and the pressure of continuous compression of class hours, the teaching reform scheme of CAD is presented in three aspects including teaching means, teaching methods and evaluation methods. According to different knowledge points in CAD teaching, 121 micro-videos with averaged duration of 3–5 minutes were recorded. Then a network course named computer drawing micro-course was developed on the platform of Chaoxing Xuexitong, which supports online study on personal mobile devices such as mobile phones and iPad in fragmentated time. Based on the micro-videos, the task-driven method and flipped classroom are adopted to carry out teaching, which could shorten the class time by 1/4 and focus on the cultivation of students’ innovative learning ability. What’s more, theory examination of CAD is cancelled, but the completion of micro-video self-study, homework, performance in flipped classroom, creation of 3D model and examination on computer are all included in the assessment, aiming to strengthen the management of learning process and the practical drawing ability with computer. Compared with the traditional classes, the pilot classes that adopted the scheme not only shorten the class hour, but also raises the average score of final examination on computer by about 4 scores, which demonstrates the feasibility of the proposed teaching reform scheme.
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