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  1. Soft robotics offer unusual bioinspired solutions to challenging engineering problems. Colorful display and morphing appendages are vital signaling modalities used by natural creatures to camouflage, attract mates, or deter predators. Engineering these display capabilities using traditional light emitting devices is energy expensive and bulky and requires rigid substrates. Here, we use capillary-controlled robotic flapping fins to create switchable visual contrast and produce state-persistent, multipixel displays that are 1000- and 10-fold more energy efficient than light emitting devices and electronic paper, respectively. We reveal the bimorphic ability of these fins, whereby they switch between straight or bent stable equilibria. By controlling the droplets temperature across the fins, the multifunctional cells simultaneously exhibit infrared signals decoupled from the optical signals for multispectral display. The ultralow power, scalability, and mechanical compliance make them suitable for curvilinear and soft machines. 
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    Free, publicly-accessible full text available June 30, 2024
  2. Abstract Superposing pre-stress on a SS304 sheet metal blank in biaxial tension and performing a single point incremental forming operation on the stretched blank is investigated experimentally. By applying a pre-stress to the sheet metal blank prior to incremental forming, the resulting microstructural change can be affected to obtain functionally graded materials according to the intended application. In austenitic stainless steels, this variation of the stress states alters the phase transformation, specifically the martensitic transformation kinetics, by influencing key process parameters, such as process force, temperature, and equivalent plastic strain. The phase transformation in truncated square pyramids is measured using magnetic induction. These measurements validate the effectiveness of the stress superposition method for achieving the desired mechanical properties based on altering the final microstructure of a simple geometry. 
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  3. Chinn, C. ; Tan, E. ; Chan, C. ; Kali, Y. (Ed.)
    Computational thinking (CT) is ubiquitous in modern science, yet rarely integrated at the elementary school level. Moreover, access to computer science education at the PK-12 level is inequitably distributed. We believe that access to CT must be available earlier and implemented with the support of an equitable pedagogical framework. Our poster will describe our Accessible Computational Thinking (ACT) research project exploring professional development with elementary teachers on integrating computational thinking with Culturally Responsive Teaching practices. 
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  4. Chinn, C. ; Tan, E. ; & Kali, Y. (Ed.)
    Computational thinking (CT) is ubiquitous in modern science, yet rarely integrated at the elementary school level. Moreover, access to computer science education at the PK-12 level is inequitably distributed. We believe that access to CT must be available earlier and implemented with the support of an equitable pedagogical framework. Our poster will describe our Accessible Computational Thinking (ACT) research project exploring professional development with elementary teachers on integrating computational thinking with Culturally Responsive Teaching practices. 
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  5. Abstract

    Theβ-delayed neutron-emission probabilities of 28 exotic neutron-rich isotopes of Pm, Sm, Eu, and Gd were measured for the first time at RIKEN Nishina Center using the Advanced Implantation Detector Array (AIDA) and the BRIKEN neutron detector array. The existingβ-decay half-life (T1/2) database was significantly increased toward more neutron-rich isotopes, and uncertainties for previously measured values were decreased. The new data not only constrain the theoretical predictions of half-lives andβ-delayed neutron-emission probabilities, but also allow for probing the mechanisms of formation of the high-mass wing of the rare-earth peak located atA≈ 160 in ther-process abundance distribution through astrophysical reaction network calculations. An uncertainty quantification of the calculated abundance patterns with the new data shows a reduction of the uncertainty in the rare-earth peak region. The newly introduced variance-based sensitivity analysis method offers valuable insight into the influence of important nuclear physics inputs on the calculated abundance patterns. The analysis has identified the half-lives of168Sm and of several gadolinium isotopes as some of the key variables among the current experimental data to understand the remaining abundance uncertainty atA= 167–172.

     
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  6. null (Ed.)