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Hybrid transmissions have attracted great attention in the automotive industry due to their energy-saving, low-emission properties, and have become a focus of research and development. This paper presents a new method to design the configuration of two mode power split hybrid transmission using the combination of the simple planetary gear trains (PGT). For this purpose, the hybrid transmission structure is divided into two substructures, which achieve different operation modes respectively. Then the output of one substructure is reconnected with the components of another substructure to obtain the complete hybrid transmission configuration. In addition, by adding additional shifting elements, the hybrid configurations can also realize the fixed gear mode as a traditional automatic transmission. As a result, 38 hybrid transmissions are obtained, and the kinematic analysis of a new configuration is performed for the subsequent optimization. Furthermore, using this decomposition and recombination method, the hybrid transmissions with multiple PGTs and different operation modes can be synthesized by changing the predefined modes. [ABSTRACT FROM AUTHOR]

Conventional reinforced concrete piers are vulnerable to severe compressive damage under strong earthquake conditions and are difficult to quickly rehabilitate. This paper develops a new type of composite pier, consisting of ultra-high-performance concrete (UHPC) and reinforced concrete (RC). This UHPC-RC composite pier uses a UHPC cover outside of an RC core to achieve a high load-carrying capacity and mitigate compressive damage. An experiment is performed to evaluate the performance of the UHPC-RC composite pier under cyclic deformation. The crack development, ultimate failure modes, and load-carrying capacities of the pier are observed. Because of the extraordinary compressive strength of UHPC, the composite pier suffers little compressive damage under large lateral deformations. The composite pier fails as a result of fracturing of the reinforcement. A numerical model is developed to reproduce the cyclic behavior of the composite pier. On the basis of the verified numerical model, a parametric analysis is used to investigate the influence of the thickness of the UHPC cover and the axial load ratio. Finally, an approach is recommended for designing composite piers. [ABSTRACT FROM AUTHOR]

Foundation piles can be used as a means for increasing the capacity of the foundations under static loads or, at the same time, can be regarded as an additional source of energy dissipation for the structure during strong motion. Under multi-axial loading, the ultimate capacity of a pile group is closely connected with the attainment of the flexural strength in the piles, which can in turn vary significantly according to the specific load path followed. Nonetheless, the design of piled foundations is still based on an independent evaluation of the vertical and horizontal capacities without accounting for the interaction between the several loads acting on the footing. To overcome this issue, in this paper a simplified numerical procedure for evaluating the capacity of piled foundations under multi-axial loading conditions is developed, which is based on the lower bound theorem of plastic limit analysis. On the basis of the numerical results, an analytical model of ultimate limit state surface is proposed, representing the force combinations that activate global plastic mechanisms of the soil–piles system. The identification of the ultimate surface necessitates a limited number of parameters having a clear physical meaning. The ultimate surface can lead to an optimised design of pile groups, allowing for a better control of the ultimate capacity as a function of the expected load patterns under static and dynamic conditions. In structural analysis, the ultimate surface can also be regarded as a bounding surface of a plasticity-based macroelement for piled foundations to account for the nonlinear features of the soil–pile system. [ABSTRACT FROM AUTHOR]

After finalization of process flow for the capacity expansion of an Integrated Steel Plant, considering the overall design requirements and inter-relationship amongst new and existing facilities, overall layout is developed on available space. Optimization of layout is proposed considering sizes, locational relationship of new units with existing operating units, required limiting conditions, transportation logistics and other auxiliary facilities. Prime objective of layout optimization should be proper utilization of available space which has been identified for expansion. Optimized layout can be developed through 3D integrated approach, which considers a common digital model of the entire plant. It can be achieved by merging the engineering output from various vendors, merging the model of existing plants obtained from works, surveys, and vendors so as to create a seamless layout. The final layout shall be best possible and can be executed in time bound manner. [ABSTRACT FROM AUTHOR]

This paper introduces a new approach for predicting load carrying capacity of circular section piles and helical piles in frozen ice-rich soils based on ground's freezing temperature and the temperature-dependent cohesion. Results obtained using this approach were validated against a field measured load carrying capacity for model single-helix helical piles, steel open-ended pipe piles, and cylindrical concrete piles in unfrozen and frozen Leda clay. The piles were first tested before wintertime while the ground was in unfrozen condition. The measured load carrying capacity in the unfrozen condition agreed well with the predicted capacity obtained from a modified previous design model for helical piles and the alpha method for the circular section piles. Modified formulae from these models were developed and used for predicting the load carrying capacity of the test piles in the ground after freezing. The predicted pile capacities agreed well with the measured load carrying capacities in the frozen ground. The introduced design approach was beneficial in providing accurate predictions for different pile types, under different loading conditions, and using readily obtained input parameters (i.e., ground temperature and the temperature-dependent cohesion strength). The presence of a snow layer on the ground surface reduced the frost depth penetration and led to a significant reduction of the load carrying capacity of the test piles particularly the helical piles. [ABSTRACT FROM AUTHOR]

Collaborative robotics and additive manufacturing are two enabling technologies of the Industry 4.0 manufacturing paradigm. Their synergic integration requires novel and effective design approaches, aiming to the development of new reconfigurable solutions for customised processes and products. This work presents an integrated approach that exploits the capabilities of Cobots to mimic the repetitive and exhausting operator's movements as well as the competitive advantages offered by additive manufacturing to realize tailored equipment. In particular, the case study shows the development of a customised device for the manipulation of biomedical components by means of a Cobot, which is introduced in a workstation to replace manual operations. Moreover, the flexibility and the effectiveness of a Cobot can be improved thanks to customised devices for gripping and pick-and-place operations based on a specific application. During the development phase, we simulated the assembly process, and tested different options. The final configuration, with conformal circuits and suction cups, can pick, manipulate and assembly the biomedical components, and thanks to a Fused Filament Fabrication technology is additively manufactured. In conclusion, this developed prototypal solution proves the real capabilities offered by integrating Cobots and additive manufacturing for the lean automation of a biomedical workstation. [ABSTRACT FROM AUTHOR]

Structural fire protection design in the United States is based on prescriptive fire-resistance ratings of individual load-bearing elements which are derived from standard fire testing, e.g. ASTM E119. In standard fire testing, a custom-built gas furnace is traditionally used to heat a test specimen by following the gas temperature-time curve prescribed in the ASTM E119 standard. The span length of the test specimen seldom exceeds 6 m due to the size limitations of available furnaces. Further, the test specimen does not incorporate realistic structural continuity. This paper presents a basis for designing an ASTM E119 fire environment in a large compartment of about 10 m wide, 7 m deep and 3.8 m high constructed in the National Fire Research Laboratory of the National Institute of Standards and Technology. Using the designed fire parameters which include heat release rate curve and opening condition (size and configuration), a full-scale experiment was carried out on December 20, 2018. The measured average upper layer gas temperature curve was consistent with the E119 fire curve. The maximum difference between the measured curve and the E119 fire curve towards the end of the test was about 70 ∘ C (7%). The study indicates that by proper design and control, the time-temperature curve for the standard fire testing may be approximated in a real compartment. [ABSTRACT FROM AUTHOR]

The overwhelming majority of the work involved in the development of external medical devices, as orthoses, consists in applying the companies' empirical knowledge. However, this non structured method, in some cases, may lead to incomplete, inadequate or low products quality. This fact precludes the patient to use the device for long term and consequently the rehabilitation desired effect promoted by the orthosis is compromised. Based on that, to promote a superior product quality, different knowledge from several domains should be considered and should interact in order to achieve a common goal, during the development stages. Additionally, when the development concerns medical devices, the users' needs and users' interface and way to use it gain a major importance. The combination of these different factors is a difficult task and is usually overlooked by the companies. This fact demonstrates the importance of the implementation of a design approach for the development of medical devices, which will permit to plan and structure each stage of the products' development. According to that, the goal of this study was to develop an innovative design approach for the development of an articulated external medical device (articular orthoses) based on the most significant moments during the device's usage. [ABSTRACT FROM AUTHOR]

The paper presents a novel machine tool design approach which is based on the surface generation simulation and evaluation. This design approach bridges the gap between the machine tool performance and the surface topography generation, in view of the machine tool performance realizing the surface topography's prediction. The main influential factors of surface topography in multi-scale are discussed and modeled by different methods. In addition, by introducing the test software at the early machine tool design stage, the surface topography indicators' disparity between the simulation results and the design requirements are contrasted, which can indicate directions for the machine parameters' optimal design, such as the straightness and the dynamic performance. An ultra-precision fly cutting machine tool was designed under the guidance of this approach, and machining trials were carried out to evaluate and validate the approach and simulations presented. [ABSTRACT FROM AUTHOR]

Formative development method (FODEM) is a multithreaded design approach that was originated to support the design and development of various types of educational technology innovations, such as learning tools, and online study programmes. The threaded and agile structure of the approach provides flexibility to the design process. Intensive stakeholder feedback is a vital aspect of FODEM. As a formative method that emphasizes research-orientation and evaluation through the entire development process, this article proposes that FODEM is fundamentally also a research and development method. FODEM provides tools to conceptualize the development process via its distinguishing feature, namely a dynamic thread structure. FODEM can be used to manage, analyse and visualise the overall design process at different stages. FODEM can also be used to create different conceptulisations of a design process in order to identify successes and failures. [ABSTRACT FROM AUTHOR]

In this paper, the characteristics of forces in active control systems connected to adjacent levels of a building are analyzed. The following characteristics are observed: (1) active control can provide significantly superior supplemental damping to a building, but causes a small frequency shift; (2) the linear quadratic regulator (LQR)-based control force is composed of an elastic restoring force component and a damping force component, where the damping force is almost identical to the total control force, however, the elastic restoring force is very small; and (3) the active control forces prevent motion most of the time during the entire control process. These three characteristics imply that active control systems connected to adjacent levels of a building behave like passive damping devices with adjustable parameters, namely damping characteristics in an active control, which is the mechanism used by semi-active control devices to reach similar performance as active control systems. Two indices are defined to quantify the damping characteristics of control forces in active control systems. These two indices can also be used to quantify the capacity of semi-active control to achieve the performance of active control. Based on the above observations, two principles are founded for optimization of parameters of semi-active control devices and passive dampers. The first is that the maximum output force of a semi-active or passive device to be designed is identical to an active device, called "design principle". The other is the response equivalent principle, which states that the response of a building with semi-active or passive devices is the same as with active devices when the same maximum output force is applied. The design procedure for semi-active control devices and passive dampers is described in detail. Finally, numerical simulations of two benchmark problems is conducted to demonstrate the damping characteristics of active control and investigate the capacity of semi-active control to achieve the same performance as active control. [ABSTRACT FROM AUTHOR]