698 research outputs found
Bone in vivo: Surface mapping technique
Bone surface mapping technique is proposed on the bases of two kinds of
uniqueness of bone in vivo, (i) magnitude of the principal moments of inertia,
(ii) the direction cosines of principal axes of inertia relative to inertia
reference frame. We choose the principal axes of inertia as the bone coordinate
system axes. The geographical marks such as the prime meridian of the bone in
vivo are defined and methods such as tomographic reconstruction and boundary
development are employed so that the surface of bone in vivo can be mapped.
Experimental results show that the surface mapping technique can both reflect
the shape and help study the surface changes of bone in vivo. The prospect of
such research into the surface shape and changing laws of organ, tissue or cell
will be promising.Comment: 9 pages, 6 figure
Stability manifolds of Kuznetsov components of prime Fano threefolds
Let be a cubic threefold, quartic double solid or Gushel--Mukai
threefold, and be its Kuznetsov
component. We show that a stability condition on is
Serre-invariant if and only if its homological dimension is at most . As a
corollary, we prove that all Serre-invariant stability conditions on
form a contractible connected component of the stability
manifold.Comment: 19 pages, comments are very welcome
Intelligent Tutoring System: Experience of Linking Software Engineering and Programming Teaching
The increasing number of computer science students pushes lecturers and
tutors of first-year programming courses to their limits to provide
high-quality feedback to the students. Existing systems that handle automated
grading primarily focus on the automation of test case executions in the
context of programming assignments. However, they cannot provide customized
feedback about the students' errors, and hence, cannot replace the help of
tutors. While recent research works in the area of automated grading and
feedback generation address this issue by using automated repair techniques, so
far, to the best of our knowledge, there has been no real-world deployment of
such techniques. Based on the research advances in recent years, we have built
an intelligent tutoring system that has the capability of providing automated
feedback and grading. Furthermore, we designed a Software Engineering course
that guides third-year undergraduate students in incrementally developing such
a system over the coming years. Each year, students will make contributions
that improve the current implementation, while at the same time, we can deploy
the current system for usage by first year students. This paper describes our
teaching concept, the intelligent tutoring system architecture, and our
experience with the stakeholders. This software engineering project for the
students has the key advantage that the users of the system are available
in-house (i.e., students, tutors, and lecturers from the first-year programming
courses). This helps organize requirements engineering sessions and builds
awareness about their contribution to a "to be deployed" software project. In
this multi-year teaching effort, we have incrementally built a tutoring system
that can be used in first-year programming courses. Further, it represents a
platform that can integrate the latest research results in APR for education
Pressure driven screening of Ni spin results in cuprate-like high- superconductivity in LaNiO
Beyond 14GPa of pressure, bi-layered LaNiO was recently found to
develop strong superconductivity above the liquid nitrogen boiling temperature.
An immediate essential question is the pressure-induced qualitative change of
electronic structure that enables the exciting high-temperature
superconductivity. We investigate this timely question via a numerical
multi-scale derivation of effective many-body physics. At the atomic scale, we
first clarify that the system has a strong charge transfer nature with
itinerant carriers residing mainly in the in-plane oxygen between spin-1
Ni ions. We then elucidate in eV- and sub-eV-scale the key physical
effect of the applied pressure: It induces a cuprate-like electronic structure
through partially screening the Ni spin from 1 to 1/2. This suggests a
high-temperature superconductivity in LaNiO with microscopic
mechanism and (-wave) symmetry similar to that in the cuprates
Reconstructing the First Metatarsophalangeal Joint of Homo naledi
The aim of the present study was to develop a new method to reconstruct damaged metatarsophalangeal joint (MTPJ) of Homo naledi's fossil and to deepen the understanding of the first metatarsal head (FMH) morphological adaptation in different gait patterns. To this purpose three methods were introduced. The first served to compare the anthropometric linear and volumetric measurements of Homo naledi's MTPJ to that of 10 various athletes. The second was employed to measure curvature diameter in FMH's medial and lateral grooves for sesamoid bones. The third was used to determine the parallelism between medial and lateral FMH grooves. The anthropometric measurements of middle-distance runner to the greatest extent mimicked that of Homo naledi. Thus, it was used to successfully reconstruct the damaged Homo naledi's MTPJ. The highest curvature diameter of medial FMH groove was found in Homo naledi, while in lateral FMH groove it was the highest in volleyball player, suggesting their increased bear loading. The parallelism of medial and lateral FMH grooves was observed only in Homo naledi, while in investigated athletes it was dis-parallel. Athletes' dis-paralleled structures make first MTPJ simple flexion movement a complicated one: not rotating about one axis, but about many, which may result in bringing a negative effect on running. In conclusion, the presented method for the reconstruction of the damaged foot bone paves the way for morphological and structural analysis of modern population and fossil hominins' gait pattern
- …