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Faulty programming of control functions in Building Automation and Control Systems (BACS) might result in inefficient building operations. To reduce programming errors, an automated implementation process of control functions might be a promising solution. Recently, Building Information Modeling (BIM) contributes to digitizing building construction projects but is rarely used in the planning and implementation of control functions in BACS. The control description in BIM also remains unclear. Regarding these problems, a control documentation method for BIM and an automated control implementation approach can simplify control implementation in BACS and hence improve the building operation. In the previous work, we developed the MODI method for a structured planning process of mode-based control algorithms for building energy systems. This method showed the potential to support digitized control planning and implementation in BACS. Based on this, in this paper, we introduce a documentation method to report mode-based control algorithms in the industrial foundation class (IFC), enabling data sharing among BIM, and a software-assisted approach to automatically generate PLC codes for implementing these algorithms. The case study demonstrates the documentation of a desired mode-based control strategy for an energy supply network in IFC and the implementation of this strategy in a PLC program. In the simulation phase, we test the implemented control strategy to verify the functionalities of the PLC program. The results prove that mode-based control strategies can be fully automatically implemented in a PLC program based on IFC data.

In this paper,a high strength Al-4.82Mg-0.75Sc-0.49Mn-0.28Zr (Al–Mg-Sc-Mn) alloy was prepared by selective laser melting (SLM). The effects of laser power on microstructures, relative density, and mechanical properties of SLM-fabricated Al–Mg-Sc-Mn alloy were studied. The results shown that the bimodal structure with an ultra-equiaxed grain and columnar crystal is formed in Slammed-fabricated Al–Mg-Sc-Mn alloy. The columnar crystal is surrounded by ultra-fine equiaxed crystal, and the columnar crystal shows (001) preferred orientation, the ultra-fine equiaxed structure shows no anisotropy in SLM-fabricated alloy. With increase of laser power, the molten pool size increases during SLM process, and the samples relative density and hardness decrease as laser power increase. The relative density of SLM-fabricated Al–Mg-Sc-Mn alloy is 99.74% under the process parameters of laser power 310W and scanning speed 1200 mm/s, and the hardness of alloy is as high as 107.73 ± 1.27 HV. The tensile strength of SLM-fabricated Al–Mg-Sc-Mn alloy samples are all higher than 400 MPa, and elongations are more than 19%. The fracture morphology of SLM-fabricated Al–Mg-Sc-Mn alloy is a typical ductile fracture feature, which shows a high comprehensive mechanical property. Supersaturated solid solution is formed in Al–Mg-Sc-Mn alloy because of rapid cooling during SLM process, resulting in grain refinement and improvement of mechanical properties. Fine-grain strengthening and second phase strengthening are the main reasons for the improvement of mechanical properties of SLM-fabricated Al–Mg-Sc-Mn alloy.

A TiB2/AlMgScZr composite was fabricated by selective laser melting (SLM) with direct powder mixing. The microstructure and mechanical properties of SLM-fabricated TiB2/AlMgScZr composites were investigated. Nearly fully dense and crack-free SLM-fabricated TiB2/AlMgScZr parts were obtained. The results showed that TiB2 formed a coherent relationship with the matrix and was swallowed by the solid–liquid interface as a nucleation point to refine grains during the SLM process. In addition, some TiB2 particles did not form a coherent relationship with the matrix, moving the solid–liquid interface at the grain boundary, which reduced the recrystallization fraction and refined the grains significantly. TiB2 also promoted the precipitation of Al3Sc and Al3Zr phases and increased the volume fraction of the Al3Sc and Al3Zr phases during the SLM process. The SLM-fabricated TiB2/AlMgScZr composites showed a very high ultimate tensile strength of ∼483 MPa and excellent ductility of ∼15.8%, which are higher than those of wrought Al alloys. The solid solubility of the Mg element slightly increased in the SLM-fabricated TiB2/AlMgScZr composites because of the high heating and cooling rate during the SLM process. The high heating and cooling rate caused discontinuous strain and Portevin–Le Chatelier effect and weakened the strengthening effect of TiB2 in SLM-fabricated TiB2/AlMgSc composites.

ObjectiveThe aim of this meta-analysis was to evaluate the effect of whole-body vibration training on lower limb motor function in children with cerebral palsy in randomized-controlled trials (RCTs).MethodsTwo independent reviewers systematically searched the records of nine databases (PubMed, Cochrane, Web of Science, EMBASE, CNKI, etc.) from inception to December 2022. Tools from the Cochrane Collaboration were used to assess risk of bias. Standard meta-analyses were performed using Stata 16.0 and Revman 5.3. For continuous variables, the arms difference was calculated as the weighted mean difference (WMD) between the values before and after the intervention and its 95% confidence interval (95% CI).ResultsOf the 472 studies identified, 13 (total sample size 451 participants) met the inclusion criteria. Meta-analysis showed that WBV training could effectively improve GMFM88-D [WMD = 2.46, 95% CI (1.26, 3.67), PConclusionWBV training is more effective than other types of conventional physical therapy in improving the lower limb motor function of children with cerebral palsy. The results of this meta-analysis strengthen the evidence of previous individual studies, which can be applied to the clinical practice and decision-making of WBV training and rehabilitation in children with cerebral palsy.

BackgroundA vital objective to treat people with cerebral palsy (CP) is to increase gait velocity and improve gross motor function. This study aimed to evaluate the relative effectiveness of gait training interventions for persons with CP.MethodsStudies published up to October 26, 2022 were searched from four electronic databases [including Medline (via PubMed), Web of Science, Embase and Cochrane]. Studies with randomized controlled trials (RCTs), people with CP, comparisons of different gait training interventions and outcomes of gait velocity and gross motor function measures (GMFM) were included in this study. The quality of the literature was evaluated using the risk of bias tool in the Cochrane Handbook, the extracted data were analyzed through network meta-analysis (NMA) using Stata16.0 and RevMan5.4 software.ResultsTwenty RCTs with a total of 516 individuals with CP were included in accordance with the criteria of this study. The results of the NMA analysis indicated that both external cues treadmill training (ECTT) [mean difference (MD) = 0.10, 95% confidence interval CI (0.04, 0.17), P < 0.05] and partial body weight supported treadmill training (BWSTT) [MD = 0.12, 95% CI (0.01, 0.23), P < 0.05] had better gait velocity than over ground gait training (OGT), BWSTT [MD = 0.09, 95%CI(0.01,0.18), P < 0.05] had a better gait velocity than robot-assisted gait training (RAGT), BWSTT [MD = 0.09, 95% CI (0.06, 0.13) P < 0.05] had a better gait velocity than treadmill training (TT), and BWSTT [MD = 0.14, 95% CI (0.07, 0.21), P < 0.05] had a better gait velocity than conventional physical therapy (CON). The SUCRA ranking indicated that BWSTT optimally improved the gait velocity, and the other followed an order of BWSTT (91.7%) > ECTT (80.9%) > RAGT (46.2%) > TT (44%) > OGT (21.6%) > CON (11.1%). In terms of GMFM, for dimension D (GMFM-D), there was no statistical difference between each comparison; for dimension E (GMFM-E), RAGT [MD = 10.45, 95% CI (2.51, 18.40), P < 0.05] was significantly more effective than CON. Both SUCRA ranking results showed that RAGT improved GMFM-D/E optimally, with rankings of RAGT (69.7%) > TT (69.3%) > BWSTT (67.7%) > OGT (24%) > CON (20.3%), and RAGT (86.1%) > BWSTT (68.2%) > TT (58%) > CON (20.1%) > OGT (17.6%) respectively.ConclusionThis study suggested that BWSTT was optimal in increasing the gait velocity and RAGT was optimal in optimizing GMFM in persons with CP. Impacted by the limitations of the number and quality of studies, randomized controlled trials with larger sample sizes, multiple centers, and high quality should be conducted to validate the above conclusion. Further studies will be required to focus on the total duration of the intervention, duration and frequency of sessions, and intensity that are optimal for the promotion of gait ability in this population.Systematic review registrationhttps://doi.org/10.37766/inplasy2022.10.0108, identifier: INPLASY2022100108.

In this paper, high-silicon Al–42Si alloy was prepared by selective laser melting (SLM) with different process parameters. Microstructures evolution and defects formation were studied and process parameters were optimized. The results shown that the density of SLM-fabricated Al–42Si alloy increases as input energy density increases. The highest and lowest density of SLM-fabricated Al–42Si alloy are obtained, when input energy density is 42.9J/mm3 and 33.8J/mm3 respectively. The microstructures of Al–42Si alloy fabricated by selective laser melting is mainly composed of primary silicon phase and eutectic silicon phase, which is distinct from casting alloy because of diffient grains size and shapes of the primary silicon. With higher energy density, larger size of the primary silicon observed during process due to higher heat released by powder. The size of primary silicon phase particles is in the range of 2.9–9.4μm, and the size of molten pool during SLM process is in the range of 125 ± 10μm–140 ± 10μm in this study. Also the hardness of SLM-fabricated Al–42Si alloy increases as input energy density increases between 40.0J/mm3 and 42.9J/mm3. After heat treatment, the residual stress is eliminated, microstructure stability and homogeneous of SLM-fabricated Al–42Si alloy are improved. The silicon distribution is more uniform and sizes increases about 1∼2μm, and the hardness decreases after heat treatment. The optimal SLM parameters for Al–42Si alloy are laser power of 320W, scanning speed of 1355 mm/s, layer thickness of 50μm and scanning space of 110μm.

The microstructures and morphologies of directionally solidified Ti–47Al alloys with different growth rates ranging from 1 to 200 μm/s were investigated using the Bridgman directionally solidified method. The results showed that numerous columnar grains were formed along the growth direction with the onset of directional solidification. With a variation in the growth rate, the solid/liquid interface changed from a flat to cellular and to dendritic interface. The flat-to-cellular interface transition rate of the Ti–47Al alloy varied from 1 to 3 μm/s. When the growth rate was higher than 10 μm/s, the solid/liquid interface showed typical dendritic growth. During the directional solidification process, the main phase of the directionally solidified Ti–47Al alloy was the α phase, which can be attributed to the solute segregation, supercooling of the components, and contamination of the alloy melt by the Y2O3 ceramic shell. After reaching the steady growth state during the directional solidification process, the solidification path of the alloy was: L→α→α+γ→(α2+γ) + γ. With an increase in the growth rate, the primary dendrite spacing (λ) and lamellar spacing (λs) of the alloy decreased gradually.

The growing share of renewable energy sources in building energy systems leads to more complex energy conversion and distribution systems. The current process of developing appropriate control functions for energy systems is insufficient and consequently error-prone. Regarding this problem, a new method is expected to systematically develop appropriate control functions for buildings and reduce design errors in this process. This paper introduces the MODI method, aiming at a structured development process of mode-based control algorithms to reduce errors in the early design stages of buildings. A complete framework and a standardized application process of the MODI method will be established to systematically design mode-based control algorithms described through signal-interpreted Petri nets. Furthermore, we performed a simulation-assisted evaluation approach to test and improve the performance of the control algorithms generated by MODI. In a case study, we applied MODI to develop a mode-based control strategy for an energy system containing heating and cooling supply networks. The desired control strategy was tested and tuned in a simulation phase. Compared to a reference control, the mode-based control algorithm shows an improvement in system efficiency by 4% in winter and 8% during the transitional season phase.