Designing for Student-Directedness: How K–12 Teachers Utilize Peers to Support Projects

Student-directed projects—projects in which students have individual control over what they create and how to create it—are a promising practice for supporting the development of conceptual understanding and personal interest in K–12 computer science classrooms. In this article, we explore a central (and perhaps counterintuitive) design principle identified by a group of K–12 computer science teachers who support student-directed projects in their classrooms: in order for students to develop their own ideas and determine how to pursue them, students must have opportunities to engage with other students’ work. In this qualitative study, we investigated the instructional practices of 25 K–12 teachers using a series of in-depth, semi-structured interviews to develop understandings of how they used peer work to support student-directed projects in their classrooms. Teachers described supporting their students in navigating three stages of project development: generating ideas, pursuing ideas, and presenting ideas. For each of these three stages, teachers considered multiple factors to encourage engagement with peer work in their classrooms, including the quality and completeness of shared work and the modes of interaction with the work. We discuss how this pedagogical approach offers students new relationships to their own learning, to their peers, and to their teachers and communicates important messages to students about their own competence and agency, potentially contributing to aims within computer science for broadening participation.

Hyper-Redundant Manipulator Capable of Adjusting Its Non-Uniform Curvature with Discrete Stiffness Distribution

Hyper-redundant manipulators are widely used in minimally invasive surgery because they can navigate through narrow passages in passive compliance with the human body. Although their stability and dexterity have been significantly improved over the years, we need manipulators that can bend with appropriate curvatures and adapt to complex environments. This paper proposes a design principle for a manipulator capable of adjusting its non-uniform curvature and predicting the bending shape. Rigid segments were serially stacked, and elastic fixtures in the form of flat springs were arranged between hinged-slide joint segments. A manipulator with a diameter of 4.5 mm and a length of 28 mm had been fabricated. A model was established to predict the bending shape through minimum potential energy theory, kinematics, and measured stiffnesses of the flat springs. A comparison of the simulation and experimental results indicated an average position error of 3.82% of the endpoints when compared to the total length. With this modification, the manipulator is expected to be widely used in various fields such as small endoscope systems and single-port robot systems.

Design Maps of TRPM8 as a Thermometer for Cold Detection

The menthol sensor TRPM8 can be activated by cold and thus serves as a thermometer in a primary afferent sensory neuron for noxious cold detection. However, the underlying design principle is unknown. Here, a hairpin topological structural model and graph theory were prepared to test a role of the cold-dependent hairpin formation in the cold-evoked gating pathway of TRPM8. The results showed that the formation of a large lipid-dependent hairpin initiates a low temperature threshold in favor of TRPM8 activation. Furthermore, two smaller hairpins, which enhance the coupled interactions of the voltage-sensor-like domain with both the pore domain and the TRP domain, can stabilize the cold efficacy and work as a fuse to prevent cold denaturation. The cold-induced hairpin rearrangements along the gating pathway may be necessary for the high cold sensitivity. This hairpin model may provide a structural basis for activation of the thermo-gated TRP channels at low temperature.

Terahertz microscope with oblique subwavelength illumination: design principle

It is shown that the image contrast in the air when using a microscope based on dielectric microparticles with a size of the order of wavelength can be significantly enhanced with the help microparticles that provide the formation of the radiation localisation region at an angle to the direction of radiation incidence (at an angle to the optical axis). For this purpose, a screen is placed in front of the particle, which blocks part of the incident beam, forming a photonic hook or a photonic jet (terajet) with oblique illumination in the near field.

Development of the Modularity Measure for Assembly Process Structures

This study is aimed at exploring the problem of quantification of process modularity degree. Modularity as a system design principle is apprehended here as the extent to which processes can be decomposed into modules to be executed in parallel and/or in series. For this purpose, a new method is proposed to measure relative modularity of different assembly process structures. This method is compared with other relative modularity measures, namely singular value modularity index, degree of process module, and process module independence, in order to verify its effectiveness. For this purpose, selected representative types of assembly process structures are used. This testing proved that the proposed relative modularity indicator for manufacturing and/or assembly process structures reflects the expected system property in adequate way.

Anisotropic charge trapping in phototransistors unlocks ultrasensitive polarimetry

Being able to probe the polarization states of light is crucial for applications from medical diagnostics and bio-inspired navigation to information encryption and quantum computing. Current state-of-the-art polarimeters based on anisotropic semiconductors enable direct linear dichroism photodetection without the need for bulky and complex external optics. However, their polarization sensitivity is restricted by the inherent optical anisotropy, leading to low dichroic ratios of typically smaller than ten. Here, we unveil an effective and general design rule to achieve a more than 2,000-fold enhanced polarization sensitivity by exploiting a light-induced anisotropic gating effect in organic phototransistors. The polarization-dependent trapping of photogenerated charge carriers provides an anisotropic photo-induced gate for current amplification, which has resulted in an extremely high dichroic ratio of over 1.2×104, more than two orders of magnitude higher than any previous reports. These findings further enable the first demonstration of a novel miniaturized bionic celestial compass for skylight-based polarization navigation. Our results offer a fundamental design principle and a new route for the development of next-generation highly polarization-sensitive optoelectronics.

Mechanical Design and Improvement of Computer Automatic Production Line

The mechanical design amelioration of automatic production line can intelligently adjust the production rhythm of the production line on demand, control the rhythm of production scheduling according to the production process requirements, and establish a modular design mode, so it has important research value. Based on this, this paper first analyses the mechanical design principle of the automatic production line, then studies the computer control system of the automatic production line, and finally gives the amelioration measures of the mechanical design of the automatic production line.