18,014 research outputs found
The Skylab radar altimeter
A summary of the significant hardware characteristics of the S-193 altimeter experiment portion of the 1973 Skylab Mission is presented. A detailed discussion of the altimetry, oceanographic, and instrumentation technology objectives are presented along with a discussion of the major experiments associated with these objectives
Lab notebooks as scientific communication: investigating development from undergraduate courses to graduate research
In experimental physics, lab notebooks play an essential role in the research
process. For all of the ubiquity of lab notebooks, little formal attention has
been paid to addressing what is considered `best practice' for scientific
documentation and how researchers come to learn these practices in experimental
physics. Using interviews with practicing researchers, namely physics graduate
students, we explore the different experiences researchers had in learning how
to effectively use a notebook for scientific documentation. We find that very
few of those interviewed thought that their undergraduate lab classes
successfully taught them the benefit of maintaining a lab notebook. Most
described training in lab notebook use as either ineffective or outright
missing from their undergraduate lab course experience. Furthermore, a large
majority of those interviewed explained that they did not receive any formal
training in maintaining a lab notebook during their graduate school experience
and received little to no feedback from their advisors on these records. Many
of the interviewees describe learning the purpose of, and how to maintain,
these kinds of lab records only after having a period of trial and error,
having already started doing research in their graduate program. Despite the
central role of scientific documentation in the research enterprise, these
physics graduate students did not gain skills in documentation through formal
instruction, but rather through informal hands-on practice.Comment: 10 page
Novel Six-Quark Hidden-Color Dibaryon States in QCD
The recent observation of a hadronic resonance in the proton-neutron
system with isospin and spin-parity raises the possibility
of producing other novel six-quark dibaryon configurations allowed by QCD. A
dramatic example of an exotic six-quark color-singlet system is the charge
, isospin I=3, state which couples strongly to
+ The width and decay properties of such
six-quark resonances could be regarded as manifestations of "hidden-color"
six-quark configurations, a first-principle prediction of QCD -- SU(3)-color
gauge theory for the deuteron distribution amplitude. Other implications and
possible future experiments are discussed
How Effectively Are We Managing Innovation?
The writer\u27s observe that top management\u27s stated commitment to innovation has yet to be successfully infused into many organizations
Instructor perspectives on iteration during upper-division optics lab activities
Although developing proficiency with modeling is a nationally endorsed
learning outcome for upper-division undergraduate physics lab courses, no
corresponding research-based assessments exist. Our longterm goal is to develop
assessments of students' modeling ability that are relevant across multiple
upper-division lab contexts. To this end, we interviewed 19 instructors from 16
institutions about optics lab activities that incorporate photodiodes.
Interviews focused on how those activities were designed to engage students in
some aspects of modeling. We find that, according to many interviewees,
iteration is an important aspect of modeling. In addition, interviewees
described four distinct types of iteration: revising apparatuses, revising
models, revising data-taking procedures, and repeating data collection using
existing apparatuses and procedures. We provide examples of each type of
iteration, and discuss implications for the development of future modeling
assessments.Comment: 4 pages, 1 figure; under revie
Student ownership of projects in an upper-division optics laboratory course: A multiple case study of successful experiences
We investigate students' sense of ownership of multiweek final projects in an
upper-division optics lab course. Using a multiple case study approach, we
describe three student projects in detail. Within-case analyses focused on
identifying key issues in each project, and constructing chronological
descriptions of those events. Cross-case analysis focused on identifying
emergent themes with respect to five dimensions of project ownership: student
agency, instructor mentorship, peer collaboration, interest and value, and
affective responses. Our within- and cross-case analyses yielded three major
findings. First, coupling division of labor with collective brainstorming can
help balance student agency, instructor mentorship, and peer collaboration.
Second, students' interest in the project and perceptions of its value can
increase over time; initial student interest in the project topic is not a
necessary condition for student ownership of the project. Third, student
ownership is characterized by a wide range of emotions that fluctuate as
students alternate between extended periods of struggle and moments of success
while working on their projects. These findings not only extend the literature
on student ownership into a new educational domain---namely, upper-division
physics labs---they also have concrete implications for the design of
experimental physics projects in courses for which student ownership is a
desired learning outcome. We describe the course and projects in sufficient
detail that others can adapt our results to their particular contexts.Comment: 22 pages, 3 tables, submitted to Phys. Rev. PE
An atlas of 1975 GEOS-3 radar altimeter data for hurricane/tropical disturbance studies, volume 1
Geographic locations of 1975 hurricanes and other tropical disturbances were correlated with the closest approaching orbits of the GEOS-3 satellite and its radar altimeter. The disturbance locations and altimeter data were gathered for a seven-month period beginning with GEOS-3 launch in mid-April 1975. Areas of coverage were the Atlantic Ocean, the Carribean, the Gulf of Mexico, the west coast of the continental United States, and the central and western Pacific Ocean. Volume 1 contains disturbance coverage data for the Atlantic Ocean, Gulf of Mexico, and Eastern Pacific Ocean. Central and Western Pacific coverage is documented in Volume II
Towards a unification of HRT and SCOZA. Analysis of exactly solvable mean-spherical and generalized mean-spherical models
The hierarchical reference theory (HRT) and the self-consistent
Ornstein-Zernike approximation (SCOZA) are two liquid state theories that both
furnish a largely satisfactory description of the critical region as well as
the phase coexistence and equation of state in general. Furthermore, there are
a number of similarities that suggest the possibility of a unification of both
theories. Earlier in this respect we have studied consistency between the
internal energy and free energy routes. As a next step toward this goal we here
consider consistency with the compressibility route too, but we restrict
explicit evaluations to a model whose exact solution is known showing that a
unification works in that case. The model in question is the mean spherical
model (MSM) which we here extend to a generalized MSM (GMSM). For this case, we
show that the correct solutions can be recovered from suitable boundary
conditions through either of SCOZA or HRT alone as well as by the combined
theory. Furthermore, the relation between the HRT-SCOZA equations and those of
SCOZA and HRT becomes transparent.Comment: Minimal correction of some typos found during proof reading. Accepted
for publication in Phys. Rev.
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