LAYER-WISE IN-PROCESS MONITORING-AND-FEEDBACK SYSTEM BASED ON SURFACE CHARACTERISTICS EVALUATED BY MACHINE-LEARNING-GENERATED CRITERIA

In the laser powder bed fusion (PBF-LB) process, a set of parameters that are considered optimal are selected. Still, a set of parameters cannot accommodate complex model geometries, model placement in the build chamber, and unforeseen circumstances, leading to internal defects. Therefore, a new in-situ monitoring and feedback system has been developed to suppress the occurrence of lack-of-fusion (LOF) defects in the PBF-LB process. This system measures surface properties after each laser irradiation to predict whether LOF defects occur. Then, if necessary, a feedback process is performed to re-melt the same surface. Evaluation thresholds are defined by a combination of aerial surface texture parameters created in advance by machine learning of surface properties and defect occurrence. For example, a square pillar of Inconel 718 alloy built with feedback had a higher relative density than one without feedback.Mechanical Engineerin

Functional innervation of Guinea-pig bladder interstitial cells of cajal subtypes: neurogenic stimulation evokes in situ calcium transients

Several populations of interstitial cells of Cajal (ICC) exist in the bladder, associated with intramural nerves. Although ICC respond to exogenous agonists, there is currently no evidence of their functional innervation. The objective was to determine whether bladder ICC are functionally innervated. Guinea-pig bladder tissues, loaded with fluo-4AM were imaged with fluorescent microscopy and challenged with neurogenic electrical field stimulation (EFS). All subtypes of ICC and smooth muscle cells (SMC) displayed spontaneous Ca(2+)-oscillations. EFS (0.5 Hz, 2 Hz, 10 Hz) evoked tetrodotoxin (1 µM)-sensitive Ca(2+)-transients in lamina propria ICC (ICC-LP), detrusor ICC and perivascular ICC (PICC) associated with mucosal microvessels. EFS responses in ICC-LP were significantly reduced by atropine or suramin. SMC and vascular SMC (VSM) also responded to EFS. Spontaneous Ca(2+)-oscillations in individual ICC-LP within networks occurred asynchronously whereas EFS evoked coordinated Ca(2+)-transients in all ICC-LP within a field of view. Non-correlated Ca(2+)-oscillations in detrusor ICC and adjacent SMC pre-EFS, contrasted with simultaneous neurogenic Ca(2+) transients evoked by EFS. Spontaneous Ca(2+)-oscillations in PICC were little affected by EFS, whereas large Ca(2+)-transients were evoked in pre-EFS quiescent PICC. EFS also increased the frequency of VSM Ca(2+)-oscillations. In conclusion, ICC-LP, detrusor ICC and PICC are functionally innervated. Interestingly, Ca(2+)-activity within ICC-LP networks and between detrusor ICC and their adjacent SMC were synchronous under neural control. VSM and PICC Ca(2+)-activity was regulated by bladder nerves. These novel findings demonstrate functional neural control of bladder ICC. Similar studies should now be carried out on neurogenic bladder to elucidate the contribution of impaired nerve-ICC communication to bladder pathophysiology

The Development Status of the National Project by Technology Research Assortiation for Future Additive Manufacturing (TRAFAM) in Japan

The Ministry of Economy, Trade and Industry (METI) of Japan established Technology Research Association for Future Additive Manufacturing (TRAFAM) in order to develop AM technology in FY2014. The association’s mission is twofold; to develop metal Additive Manufacturing technology and to develop binder jetting-type machine for the rapid production of sand molds. The goal of TRAFAM project is the development of innovative metal AM systems that will meet the world’s highest standards and the development of AM technology for high value-added products for aerospace, medical, and transportation industries etc. In this paper, the latest development status of the project, especially the development status of the electron beam PBF type machines, the laser PBF type machine and the laser DED type machines, is introduced. In addition, the numerical simulation software for metal AM based on multi-scale and multi-physics model is introduced.Mechanical Engineerin

Electrostatic solitary waves associated with magnetic anomalies and wake boundary of the Moon observed by KAGUYA

We present observations of electrostatic solitary waves (ESWs) near the Moon by SELENE (KAGUYA) in the solar wind and in the lunar wake. SELENE is a lunar orbiter with an altitude of 100 km and measured wave electric field, background magnetic field, and fluxes of ions and electrons, etc. ESWs are categorized into three types depending on different regions of observations: ESWs generated by electrons reflected and accelerated by an electric field in the wake boundary (Type A), strong ESWs generated by bi-streaming electrons mirror-reflected over the magnetic anomaly (Type B), and ESWs generated by reflected electrons when the local magnetic field is connected to the lunar surface (Type C). ESWs of Type C often alternate with Langmuir waves