A smart conflict resolution model using multi-layer knowledge graph for conceptual design

Reducing the impact of conflicts on requirement-function-structure mapping in the early stage of product design is an important measure to achieve conceptual innovation, which relies on accurate reasoning of multi-domain knowledge. As product requirements become more personalized and diverse, traditional discrete knowledge organization and reasoning methods are difficult to adapt to the challenges of continuity and precision in conceptual solution. Knowledge graphs with complex networks have obvious advantages in association detection, knowledge visualization, and explainable reasoning of implicit knowledge, which offer innovative opportunities for conflict resolution in conceptual design. Therefore, a smart conflict resolution model using a multi-layer Knowledge Graph for Conceptual Design(mKGCD) is proposed in this study. A knowledge expression form of FBS-oriented design patent vocabulary is proposed, which is used for knowledge entity recognition and relation extraction based on natural language processing. A label mapping method based on inventive principles is used for patent classification and a four-layer semantic network for conflict resolution is constructed. Through semantic distance calculation, the designer's requirements for function/behavior/structure are smart deployed to obtain appropriate knowledge. A case study of the conceptual design of a collapsible installation and handling equipment demonstrates the feasibility of the proposed approach. The proposed method can not only meet the functional solution and innovation in the context of different design requirements, but also effectively improve the design efficiency in the iterative design process by means of multiple meanings of one graph.     

HIGSA: Human image generation with self-attention

The goal of human image generation (HIG) is to synthesize a human image in a novel pose. HIG can potentially benefit various computer vision applications and engineering tasks. The recently-developed CNN-based approach applies the attention architecture to vision tasks. However, owing to the locality in CNNs, extracting and maintaining the long-range pixel interactions input images is difficult. Thus, existing human image generation methods face limited content representation. In this paper, we propose a novel human image generation framework called HIGSA that can utilize the position information from the input source image. The proposed HIGSA contains two complementary self-attention blocks to generate photo-realistic human images, named as stripe self-attention block (SSAB) and content attention block (CAB), respectively. In SSAB, this paper establishes global dependencies of human images and computes the attention map for each pixel based on its relative spatial positions concerning other pixels. In CAB, this paper introduces an effective feature extraction module to interactively enhance both person’s appearance and shape feature representations. Therefore, the HIGSA framework inherently preserves the better appearance consistency and shape consistency with sharper details. Extensive experiments on mainstream datasets demonstrate that HIGSA achieves the state-of-the-art (SOTA) results.     

Conceptual design of a user-centric smart product-service system using self-organizing map

As an emerging IT-driven business paradigm, smart product-service system (Smart PSS), which offers not only the smart, connected product (SCP) but also its generated service as a solution bundle, has become a vital research topic. Many research efforts have been devoted to constructing the conceptual design framework by considering SCPs and services simultaneously. However, the following critical issues in Smart PSS conceptual design have not been well addressed: how to improve the solution of Smart PSS in the conceptual design stage to meet user emotional requirements. Aiming to fill the gap, this work proposes a conceptual design method for Smart PSS from the perspective of analyzing user-generated emotions/feelings. Specifically, the relevant traditional products are identified, and their public review data is used to analyze user emotions/feelings in user-product interaction. Interactive emotion board as a new design tool is presented to organize the user-generated emotions/feelings, associated design elements, and the potential design points of the initial solution. And the analytic hierarchy process (AHP) is utilized to evaluate the improved solution. To ensure the efficiency of the analysis process, the self-organizing map (SOM) algorithm is utilized in the process of clustering product samples and Kansei words. A case study of smart electric bicycle service system (SEBSS) design is used to demonstrate the performance of the proposed method. Based on the case study, the proposed approach appears effective in helping with Smart PSS conceptual design.     

Comparative analysis of Simulated Annealing,Simulated Quenching and Genetic Algorithms for optimal reservoir operation

The present study deals with the application of non-traditional optimization techniques, namely, Simulated Annealing (SA), Simulated Quenching (SQ) and Real-coded Genetic Algorithms (RGA) to a case study of Mahi Bajaj Sagar Project, India. The objective of the study is to maximize the annual net benefits subjected to various irrigation planning constraints for 75% dependable flow scenario. Extensive sensitivity analysis on various parameters used in above techniques indicated that they yielded same solution corresponding to a set of optimal combination of parameters. It is concluded that SA, SQ and RGA can be utilized for efficient planning of any irrigation system with suitable modifications.     

爆炸冲击下水底隧道的动态响应及毁伤模式研究

考虑炸药起爆、冲击波传播、冲击波与结构的相互作用以及结构的动态响应等复杂过程,基于Lagrange-Euler耦合算法,建立了水底隧道水下爆炸的全耦合数值仿真模型。通过与爆炸试验结果进行对比,验证了数值模型的可靠性;研究了水下爆炸冲击荷载作用下的水底隧道的毁伤破坏过程、空间分布规律及破坏模式。结果表明:水底隧道的破坏模式不仅与隧道自身的动力特性有关,还取决于起爆距离及炸药当量等;隧道的破坏模式为局部冲切或剥落破坏、弯曲破坏伴随着局部剥落破坏以及整体弯曲破坏。     

Surface microstructure and abrasion resistance of concrete

The influence of several surface finishing techniques on the abrasion resistance of concrete specimens of various mix compositions has been measured by means of a rolling-wheel apparatus. Microstructural features of the cement matrix components of the exposed surfaces have been studied by mercury intrusion porosimetry and microhardness determinations. The results indicate that different methods of surface finishing produce substantially different microstructural characteristics within a surface zone of a few mm maximum thickness. For the systems investigated, it was found that the abrasion resistance was determined largely by the pore structure of this surface zone.     

Utilization of water glass as an activator in the manufacturing of cementitious materials from waste by-products

In the present paper, the possibility of producing new-type cementless building materials is discussed when water glass as an activating agent is used. The experimental data are presented for a set of raw materials which normally do not show any binding ability. However, if they undergo some physico-chemical treatment and water glass is used, a solid structure of the material is formed. According to the method described here, lots of different mineral waste by-products could be activated, thus gaining binding properties.     

Influence of microcrack self-healing behavior on the permeability of Engineered Cementitious Composites

Engineered Cementitious Composite (ECC) is a family of high performance fiber reinforced cementitious composites featuring strain-hardening behavior and high tensile ductility (with tensile strain capacity of 3–5%). ECC achieves high ductility by forming multiple microcracks with crack width less than 60 μm under tension. The tight crack width of ECC naturally lends itself to low permeability even in the cracked stage. Such properties are of particular interest to hydraulic structure applications. In addition to the tight crack width, self-healing of microcracks further lowers the permeability of cracked ECC, enhancing the durability and safety of hydraulic structures. In this paper, the permeability of ECC composites under the influence of self-healing was experimentally studied. Single crack permeability tests were also conducted to directly correlate the permeability and self-healing behavior of a single crack with a given initial crack width. Additionally, an analytical model capable of predicting the permeability of ECC composites that undergo self-healing process is proposed and verified with experimental data. The research findings in the present paper can be used to accurately estimate the permeability of ECC and are expected to provide support for future design and application of ECC for hydraulic structures.     

Research on intelligent assembly method of aero-engine multi-stage rotors based on SVM and variable-step AFSA-BP neural network

The quality of the aero-engine rotors assembly determines the overall performance of the engine. Aiming at the problems of rotors assembly with different plane types, we proposes a rotor plane classification method based on SVM by using the profile data of PCA dimension reduction. Meanwhile, for the unilateral-tilt plane rotors, the three-objective rotors assembly method of coaxiality, unbalance amount and perpendicularity based on the rigid rotor model is established. For the hyperbolic paraboloid rotors, an intelligent assembly method based on AFSA-BP neural network for coaxiality, unbalance amount and perpendicularity is established. The experiment is based on the double-column ultra-precision measuring instrument and V4L vertical balancing machine and HL5UB horizontal balancing machine to measure rotors geometry and unbalance data. The experimental results show that the plane type classification accuracy can reach 99 %. The prediction error of the coaxiality of the unilateral-tilt plane rotors assembly is 5.1 μm, the prediction error of the unbalance amount is 196 g·mm, and the prediction error of the perpendicularity is 0.6 μm. The average prediction error of the coaxiality of the hyperbolic paraboloid rotors assembly is 0.9 μm, and the average prediction error of the unbalance amount is 73 g·mm, and the average prediction error of the perpendicularity is 0.2 μm. Our method provides a reliable assembly solution for aero-engine rotors assembly and meets actual assembly requirements.