Metal Alloys for Filaments in 3D Fusion Filament Modelling Printing Process

The paper presents experimental research regarding the application of specific low melting metals in the FDM process. Previous trends in the transfer of the filament from the spool to the hot-end showed that the filament undergoes specific mechanical stress during the transfer. To achieve an appropriate transfer the filament should prove stiffness and resistance to the mechanical actions of the transfer wheels. At the same time, the entrance to the hot-end creates specific resistance to the movement of the filament, and the filament undergoes important deformations. The experimental research used three materials characterized by melting temperature below 260oC: Sn-58Bi, Sn-9Zn, and Sn-3.5Ag. Sn-58Bi showed a yield stress above 50 MPa, but very low extension during the tensile test. Sn-9Zn exhibited a yield stress above 30 MPa, and about double the extension during the tensile test. Sn-3.5Ag displayed a yield stress above 25 MPa, and extension in excess of 8%. The analysis of the surface was performed, revealing that the increase of the yield stress influenced the appearance of specific prints given by the transfer wheels. The deepest prints were measured for Sn-3.5Ag and they were maximum 100 μm. The other two materials were stiffer and the prints have depths below 50 μm. According to the obtained results, each of the tested materials can be an appropriate solution to filament use for the FDM 3D printing process

Effective Strategic Management - Manager Performance

Managers are a very important component of human resources within an organization, and they make a decisive contribution to establishing and achieving the company's goals. In the context of the global development of the economy, both the roles and the tasks of the managers of any type of organization have changed; which is why the success of an enterprise / institution / school, etc. depends on the quality of managers. Exercising a performance management must transform the organization so that it becomes the "ideal employer" in which the employee is enthusiastic and devoted to his work. Through their position and role in organizations, leaders must be able to exercise effective leadership at all levels to make their employees feel valued, productive and listening; to offer opportunities for learning and improving each employee; to create a productive climate that allows the balance between work and personal life to be maintained

On the origin of the reactor antineutrino anomalies in light of a new summation model with parameterized β−\beta^{-} transitions

We investigate the possible origins of the norm and shape reactor antineutrino anomalies in the framework of a summation model (SM) where $\beta^{-}$ transitions are simulated by a phenomenological Gamow-Teller $\beta$-decay strength model. The general trends of the discrepancies to the Huber-Mueller model on the antineutrino side can be reproduced both in norm and shape. From the exact electron-antineutrino correspondence of the SM model, we predict similar distortions in the electron spectra, suggesting that biases on the reference fission-electron spectra could be at the origin of the anomalies

Utilization of granular solidification during terrestrial locomotion of hatchling sea turtles

Biological terrestrial locomotion occurs on substrate materials with a range of rheological behaviour, which can affect limb-ground interaction, locomotor mode and performance. Surfaces like sand, a granular medium, can display solid or fluid-like behaviour in response to stress. Based on our previous experiments and models of a robot moving on granular media, we hypothesize that solidification properties of granular media allow organisms to achieve performance on sand comparable to that on hard ground. We test this hypothesis by performing a field study examining locomotor performance (average speed) of an animal that can both swim aquatically and move on land, the hatchling Loggerhead sea turtle (Caretta caretta). Hatchlings were challenged to traverse a trackway with two surface treatments: hard ground (sandpaper) and loosely packed sand. On hard ground, the claw use enables no-slip locomotion. Comparable performance on sand was achieved by creation of a solid region behind the flipper that prevents slipping. Yielding forces measured in laboratory drag experiments were sufficient to support the inertial forces at each step, consistent with our solidification hypothesis

Parity Violation in Elastic Electron-Proton Scattering and the Proton's Strange Magnetic Form Factor

We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form factor of the proton as well as electroweak axial radiative corrections. The new measurement of A=-4.92 +- 0.61 +- 0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections.Comment: 4 pages, 3 figures, submitted to Physical Review Letters, Sept 199

Measurement of the vector analyzing power in elastic electron-proton scattering as a probe of double photon exchange amplitudes

We report the first measurement of the vector analyzing power in inclusive transversely polarized elastic electron-proton scattering at Q^2 = 0.1 (GeV/c)^2 and large scattering angles. This quantity should vanish in the single virtual photon exchange, plane wave impulse approximation for this reaction, and can therefore provide information on double photon exchange amplitudes for electromagnetic interactions with hadronic systems. We find a non-zero value of A=-15.4+/-5.4 ppm. No calculations of this observable for nuclei other than spin 0 have been carried out in these kinematics, and the calculation using the spin orbit interaction from a charged point nucleus of spin 0 cannot describe these data.Comment: 4 pages, 2 figures, submitted to Phys. Rev. Let

Parity-violating Electron Deuteron Scattering and the Proton's Neutral Weak Axial Vector Form Factor

We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2= 0.038 (GeV/c)2. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A=-3.51 +/- 0.57(stat) +/- 0.58(sys)ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2=0.091 (GeV/c)2, which are also consistent with theoretical predictions.Comment: 4 pages, 2 figures, submitted to Phys. Rev. Let

Parity Violation in Elastic Electron-Proton Scattering and the Proton's Strange Magnetic Form Factor

We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form factor of the proton as well as electroweak axial radiative corrections. The new measurement of A = -4.92±0.61±0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections