143,923 research outputs found
As Time Goes by ???: Revisiting Fundamentals
published or submitted for publicatio
"Thermometers" of Speculative Frenzy
Establishing unambiguously the existence of speculative bubbles is an
on-going controversy complicated by the need of defining a model of fundamental
prices. Here, we present a novel empirical method which bypasses all the
difficulties of the previous approaches by monitoring external indicators of an
anomalously growing interest in the public at times of bubbles. From the
definition of a bubble as a self-fulfilling reinforcing price change, we
identify indicators of a possible self-reinforcing imitation between agents in
the market. We show that during the build-up phase of a bubble, there is a
growing interest in the public for the commodity in question, whether it
consists in stocks, diamonds or coins. That interest can be estimated through
different indicators: increase in the number of books published on the topic,
increase in the subscriptions to specialized journals. Moreover, the well-known
empirical rule according to which the volume of sales is growing during a bull
market finds a natural interpretation in this framework: sales increases in
fact reveal and pinpoint the progress of the bubble's diffusion throughout
society. We also present a simple model of rational expectation which maps
exactly onto the Ising model on a random graph. The indicators are then
interpreted as ``thermometers'', measuring the balance between idiosyncratic
information (noise temperature) and imitation (coupling) strength. In this
context, bubbles are interpreted as low or critical temperature phases, where
the imitation strength carries market prices up essentially independently of
fundamentals. Contrary to the naive conception of a bubble and a crash as times
of disorder, on the contrary, we show that bubbles and crashes are times where
the concensus is too strong.Comment: 15 pages + 10 figure
Exegesis of Sect. III.B from “Fundamentals of the Mechanics of Continua” by E. Hellinger
This is our third and last exegetic essay on the fundamental review article DIE ALLGEMEINEN ANSÄTZE DER MECHANIK DER KONTINUA in the Encyklopädie der mathematischen Wissenschaften mit Einschluss ihrer Anwendungen, Bd. IV-4, Hft. 5 (1913) by Ernst Hellinger which contains the translation and the commentary of the remaining text starting from p. 663. The six subsections, No. 9–15, deal with the applications of the previously developed conceptual tools to formulate: an effective theory of elasticity, the dynamics of ideal fluids, models for internal friction and elastic hysteresis, a theory of capillarity, optics, the fundamental equations of electrodynamics, an introduction of the thermodynamical foundations and the relationship between the theory of continua and the theory of relativity. Hellinger refers to relevant literature while consolidating in an effective way the contemporary knowledge in 1913. Considering notational differences as being irrelevant for the characterization of the presented scientific content, Hellinger's article shows that an effective compendium of a large part of the insights given in Truesdell and Toupin and Truesdell and Noll has already been available in 1913. We include in this paper an assessment of the different roles played by pioneers, who are innovating their scientific discipline, and by erudite scholars whose role consists in re-ordering existent knowledge and advertising to a wider audience the most important technical results already obtained in a given discipline
Automatic C library wrapping Ctypes from the trenches
At some point of time many Python developers at least in computational science will
face the situation that they want to interface some natively compiled library from Python. For
binding native code to Python by now a larger variety of tools and technologies are available.
This paper focuses on wrapping shared C libraries, using Python's default Ctypes. Particularly
tools to ease the process (by using code generation) and some best practises will be stressed.
The paper will try to tell a step by step story of the wrapping and development process,
that should be transferable to similar problems
Aerospace medicine and biology. A continuing bibliography (supplement 231)
This bibliography lists 284 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1982
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Using the Internet of Things to Teach Good Software Engineering Practice to High School Students
This paper describes a course to introduce high school students
to software engineering in practice using the Internet Of
Things (IoT). IoT devices allow students to get quick, visible
results without watering down technical aspects of
programming and networking. The course has three broad
goals: (1) to make software engineering fun and applicable,
with the aim of recruiting traditionally underrepresented
groups into computing; (2) to make young students begin to
approach problems with a design mindset; and (3) to show
students that computer science, generally, and software
engineering, specifically, is about much more than
programming. The course unfolds in three segments. The first
is a whirlwind introduction to a subset of IoT technologies.
Students complete a specific task (or set of tasks) using each
technology. This segment culminates in a “do-it-yourself”
project, in which the students implement a simple IoT
application using their basic knowledge of the technologies.
The course’s second segment introduces software engineering
practices, again primarily via hands-on practical tutorials. In
the third segment of the course, the students conceive of,
design, and implement a project that uses the technologies
introduced in the first segment, all while being attentive to the
good software engineering practices acquired in the second
segment. In addition to presenting the course curriculum, the
paper also discusses a first offering of the course in a threeweek
summer intensive program in 2017, including
assessments done to evaluate the curriculum.Cockrell School of Engineerin
Special Libraries, April 1959
Volume 50, Issue 4https://scholarworks.sjsu.edu/sla_sl_1959/1003/thumbnail.jp
Systems Analysis as a Decision-Making Tool for the Library Manager
published or submitted for publicatio
Experimental evaluation of new pipe sleeve with weep holes for concrete leakage prevention
Mortar is a layer with high water absorption rate over concrete due to its porous structure. The mortar layer that frequently exposed to water or moisture is more likely to contain moisture in its layer. The example of area that is mostly exposed to water is the bathroom. The water infiltrated and trapped in the mortar slab in the bathroom will eventually increase the moisture content of the mortar slab and will raise many problems such as the deterioration of the building structure surface. Therefore, this study has been carried out to produce a technology to remove the trapped water in the mortar slab and to reduce the moisture content in the mortar layer. The infiltration rate of the water into the mortar slabs installed with the conventional pipe sleeve (T1), the circular weep-holes pipe sleeve (T2), the vertical weep-holes pipe sleeve (T3) and the inclined weep-holes pipe sleeve (T4) have been measured and the results show that T4 has recorded the highest reading of 7.74 ml/min compared to other pipe sleeves. Besides that, T4 has also recorded the highest water flow rate out of the mortar with 1.31 ml/min and recorded the lowest moisture content of 10.1%. Inclined weep-holes pipe sleeve was proven able to work better than other designs. Therefore, the New Pipe Sleeve (NPS) performance with inclined weep-holes designs are studied in depth by changing the weep-holes angles to 15°, 30°, 45°, 60° and 75° and weep-holes surface area of 6%, 8% and 10%. As a result, the weep-holes angle of 60° with 10% weep-holes surface area has recorded the highest water infiltration rate and water flow rate out of the mortar with 20.898 ml/min and 3.764 ml/min, respectively, obtaining the highest reduction of the moisture content by 3.1%. The optimum performance of the pipe sleeve with inclined weep-holes design has been proposed by using Design Expert Software and the optimum performance can be achieved with the used of the weep-holes angle of 69.55° and 10% weep-holes surface area, producing water infiltration rate of 20.4513 ml/min and water flow rate out of the mortar of 3.3795 ml/min. Therefore, application of optimise design of weep-holes has promising potential method to reduce leakage and fungi problem that normally occurred in bathroom area
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