Abstract: In order to use bitumen in hot mix asphalt, it must
have specific characteristics. There are some methods to reach these
properties. Using polymer modifiers are one of the methods to
modify the bitumen properties. In this paper the effect of Styrene-
Butadiene-Rubber that is one of the bitumen polymer modifiers on
rheology properties of bitumen is studied. In this regard, the
rheological properties of base bitumen and the modified bitumen with
3, 4, and 5 percent of Styrene-Butadiene-Rubber (SBR) were
analysed. The results show that bitumen modified with 5 percent of
SBR has the best performance than the other samples.
Abstract: This paper presents the design and characterization of
analog readout interface circuits for ion sensitive field effect
transistor (ISFET) and ion selective electrode (ISE) based sensor.
These interface circuits are implemented using MIMOS’s 0.35um
CMOS technology and experimentally characterized under 24-leads
QFN package. The characterization evaluates the circuit’s
functionality, output sensitivity and output linearity. Commercial
sensors for both ISFET and ISE are employed together with glass
reference electrode during testing. The test result shows that the
designed interface circuits manage to readout signals produced by
both sensors with measured sensitivity of ISFET and ISE sensor are
54mV/pH and 62mV/decade, respectively. The characterized output
linearity for both circuits achieves above 0.999 Rsquare. The readout
also has demonstrated reliable operation by passing all qualifications
in reliability test plan.
Abstract: The concept of national security in Iran is a
permanently effective factor in acceptance or rejection of many
international obligations. These obligations had been defined
according to the type of legislation of Iran in many aspects.
Therefore, there are several treaties at international level which
requires Iran’s security to come in contact with obligations in these
treaties in a way that an obstacle to join to them and their passage in
parliament. This issue is a typical category which every country pays
attention to be accepted in treaties or to include their national
security in that treaties and also they can see the related treaties from
this perspective, but this issue that 'what is the concept of Iran’s
national security', and 'To what extent it is changed in recent years,
especially after Islamic Revolution' are important issues that can be
criticized. Thus, this study is trying to assess singed treaties from the
perspective of Iran’s national security according of the true meaning
of treaty and to investigate how the international treaties may be in
conflict with Iran’s national security.
Abstract: On the basis of the theory of nonlinear elasticity, the
effect of homogeneous stress on the propagation of Lamb waves in
an initially isotropic hyperelastic plate is analysed. The equations
governing the propagation of small amplitude waves in the prestressed
plate are derived using the theory of small deformations
superimposed on large deformations. By enforcing traction free
boundary conditions at the upper and lower surfaces of the plate,
acoustoelastic dispersion equations for Lamb wave propagation are
obtained, which are solved numerically. Results are given for an
aluminum plate subjected to a range of applied stresses.
Abstract: In educational technology, the idea of innovation is
usually tethered to contemporary technological inventions and
emerging technologies. Yet, using long-known technologies in ways
that are pedagogically or experimentially new can reposition them as
emerging educational technologies. In this study we explore how a
subtle pivot in pedagogical thinking led to an innovative education
technology. We describe the design and implementation of an online
writing tool that scaffolds students in the evaluation of their own
informational texts. We think about how pathways to innovation can
emerge from pivots, namely a leveraging of longstanding practices in
novel ways has the potential to cultivate new opportunities for
learning. We first unpack Infowriter in terms of its design, then we
describe some results of a study in which we implemented an
intervention which included our designed application.
Abstract: Intermetallic materials are among advanced
technology materials that have outstanding mechanical and physical
properties for high temperature applications. Especially creep
resistance, low density and high hardness properties stand out in such
intermetallics. The microstructure, mechanical properties of %88Ni-
%10Cr and %2Mn powders were investigated using specimens
produced by tube furnace sintering at 900-1300°C temperature. A
composite consisting of ternary additions, a metallic phase, Fe, Cr
and Mn have been prepared under Ar shroud and then tube furnace
sintered. XRD, SEM (Scanning Electron Microscope), were
investigated to characterize the properties of the specimens.
Experimental results carried out for composition %88Ni-%10Cr and
%2Mn at 1300°C suggest that the best properties as 138,80HV and
6,269/cm3 density were obtained at 1300°C.
Abstract: Through use of novel modern/rapid processing
techniques such as screen printing and Near-Infrared (NIR) radiative
curing, process time for the sintering of sintered nickel plaques,
applicable to alkaline nickel battery chemistries, has been drastically
reduced from in excess of 200 minutes with conventional convection
methods to below 2 minutes using NIR curing methods. Steps have
also been taken to remove the need for forming gas as a reducing
agent by implementing carbon as an in-situ reducing agent, within the
ink formulation.
Abstract: There are many perceived advantages of microwave
ablation have driven researchers to develop innovative antennas to
effectively treat deep-seated, non-resectable hepatic tumors. In this
paper a coaxial antenna with a miniaturized sleeve choke has been
discussed for microwave interstitial ablation therapy, in order to
reduce backward heating effects irrespective of the insertion depth
into the tissue. Two dimensional Finite Element Method (FEM) is
used to simulate and measure the results of miniaturized sleeve choke
antenna. This paper emphasizes the importance of factors that can
affect simulation accuracy, which include mesh resolution, surface
heating and reflection coefficient. Quarter wavelength choke
effectiveness has been discussed by comparing it with the unchoked
antenna with same dimensions.
Abstract: While emerging technologies continue to emerge,
research into their use in learning contexts often focuses on a subset
of educational practices and ways of using technologies. In this study
we begin to explore the extent to which educational designs are
influenced by larger societal and education-related factors not usually
explicitly considered when designing or identifying technology-supported
education experiences for research study. We examine
patterns within and between factors via a content analysis across ten
years and 19 different journals of published peer-reviewed research
on technology-supported writing. Our findings have implications for
how researchers, designers, and educators approach technology-supported
educational design within and beyond the field of writing
and literacy.
Abstract: The article proposed intends to analyze the possibility
(and conditions) of a media regulation law in a democratic rule of law
in the twenty-first century. To do so, will be presented initially the
idea of the public sphere (by Jürgen Habermas), showing how it is
presented as an interface between the citizen and the state (or the
private and public) and how important is it in a deliberative
democracy. Based on this paradigm, the traditional perception of the
role of public information (such as system functional element) and on
the possibility of media regulation will be exposed, due to the public
nature of their activity. A critical argument will then be displayed
from two different perspectives: a) the formal function of the current
media information, considering that the digital age has fragmented
the information access; b) the concept of a constructive democracy,
which reduces the need for representation, changing the strategic
importance of the public sphere. The question to be addressed (based
on the comparative law) is if the regulation is justified in a
polycentric democracy, especially when it operates under the digital
age (with immediate and virtual communication). The proposal is to
be presented in the sense that even in a twenty-first century the media
in a democratic rule of law still has an extremely important role and
may be subject to regulation, but this should be on terms very
different (and narrower) from those usually defended.
Abstract: An important problem for the CaSO4/CaSO4･1/2H2O
Chemical heat pump (CHP) is that the material is deactivated through
repetitive reaction between hydration and dehydration in which the
crystal phase of the material is transformed from III-CaSO4 to
II-CaSO4. We investigated suppression on the phase change by adding
a sulfated compound. The most effective material was MgSO4. MgSO4
doping increased the durability of CaSO4 in the actual CHP repetitive
cycle of hydration/dehydration to 3.6 times that of undoped CaSO4.
The MgSO4-doped CaSO4 showed a higher phase transition
temperature and activation energy for crystal transformation from
III-CaSO4 to II-CaSO4. MgSO4 doping decreased the crystal lattice
size of CaSO4･1/2H2O and II-CaSO4 to smaller than that of undoped
CaSO4. Modification of the crystal structure is considered to be related
to the durability change in CaSO4 resulting from MgSO4 doping.
Abstract: Super steel materials play a vital role in the
construction and fabrication of structural, piping and pipeline
components. In assuring the integrity of onshore and offshore
operating systems, they enable life cycle costs to be minimized. In
this context, Duplex stainless steel (DSS) material related welding on
constructions and fabrications plays a significant role in maintaining
and assuring integrity at an optimal expenditure over the life cycle of
production and process systems as well as associated structures. In
DSS welding, factors such as gap geometry, shielding gas supply
rate, welding current, and type of the welding process are vital to the
final joint performance. Hence, an experimental investigation has
been performed using an engineering robust design approach
(ERDA) to investigate the optimal settings that generate optimal
super DSS (i.e. UNS S32750) joint performance. This manuscript
illustrates the mathematical approach and experimental design,
optimal parameter settings and results of the verification experiment.
Abstract: White concrete facade elements are widely used in
construction industry. It is challenging to achieve the desired
workability in casting of white concrete elements. Particle Matrix
model was used for proportioning the self-compacting white concrete
(SCWC) to control segregation and bleeding and to improve
workability. The paper presents how to reach the target slump flow
while controlling bleeding and segregation in SCWC. The amount of
aggregates, binders and mixing water, as well as type and dosage of
superplasticizer (SP) to be used are the major factors influencing the
properties of SCWC. Slump flow and compressive strength tests were
carried out to examine the performance of SCWC, and the results
indicate that the particle matrix model could produce successfully
SCWC controlling segregation and bleeding.
Abstract: To ensure student success in a non-majors biology course, a flipped classroom pedagogical approach was developed and implemented. All students were assigned online lectures to listen to before they come to class. A three hour lecture was split into one hour of online component, one hour of in class lecture and one hour of worksheets done by students in the classroom. This deviation from a traditional 3 hour in class lecture has resulted in increased student interest in science as well as better understanding of difficult scientific concepts. A pre and post survey was given to measure the interest in the subject and grades were used to measure the success rates. While the overall grade average did not change dramatically, students reported a much better appreciation of biology. Also, students overwhelmingly like the use of worksheets in class to help them understand the concepts. They liked the fact that they could listen to lectures at their own pace on line and even repeat if needed. The flipped classroom approach turned out to work really well our non-science majors and the author is ready to implement this in other classrooms.
Abstract: Removal of the widespread used drug paracetamol
from water was investigated using activated carbon originated from
dende coconut mesocarp and babassu coconut mesocarp. Kinetic and
equilibrium data were obtained at different values of pH. Both
activated carbons showed high efficiency when pH ≤ pHPZC as the
carbonil group of paracetamol molecule are adsorbed due to
positively charged carbon surface. Microporosity also played an
important role in such process. Pseudo-second order model was better
adjusted to the kinetic results. Equilibrium data may be represented
by Langmuir equation.
Abstract: The aim of this study is to investigate formability of
Al based closed cell metallic foams at high temperature. The foam
specimens with rectangular section were produced from
AlMg1Si0.6TiH20.8 alloy preform material. Bending and free
bending tests based on gravity effect were applied to foam specimens
at high temperatures. During the tests, the time-angular deformation
relationships with various temperatures were determined.
Deformation types formed in cell walls were investigated by means
of Scanning Electron Microscopy (SEM) and optical microscopy.
Bending deformation about 90° was achieved without any defect at
high temperatures. The importance of a critical temperature and
deformation rate was emphasized in maintaining the deformation.
Significant slip lines on surface of cell walls at tensile zones of
bending specimen were observed. At high strain rates, the microcrack
formation in boundaries of elongated grains was determined.
Abstract: This paper investigates simple implicit force control
algorithms realizable with industrial robots. A lot of approaches
already published are difficult to implement in commercial robot
controllers, because the access to the robot joint torques is necessary
or the complete dynamic model of the manipulator is used. In
the past we already deal with explicit force control of a position
controlled robot. Well known schemes of implicit force control are
stiffness control, damping control and impedance control. Using such
algorithms the contact force cannot be set directly. It is further
the result of controller impedance, environment impedance and
the commanded robot motion/position. The relationships of these
properties are worked out in this paper in detail for the chosen
implicit approaches. They have been adapted to be implementable
on a position controlled robot. The behaviors of stiffness control
and damping control are verified by practical experiments. For this
purpose a suitable test bed was configured. Using the full mechanical
impedance within the controller structure will not be practical in the
case when the robot is in physical contact with the environment. This
fact will be verified by simulation.
Abstract: Heat transfer due to forced convection of copper water
based nanofluid has been predicted by Artificial Neural network
(ANN). The present nanofluid is formed by mixing copper
nanoparticles in water and the volume fractions are considered here
are 0% to 15% and the Reynolds number are kept constant at 100.
The back propagation algorithm is used to train the network. The
present ANN is trained by the input and output data which has been
obtained from the numerical simulation, performed in finite volume
based Computational Fluid Dynamics (CFD) commercial software
Ansys Fluent. The numerical simulation based results are compared
with the back propagation based ANN results. It is found that the
forced convection heat transfer of water based nanofluid can be
predicted correctly by ANN. It is also observed that the back
propagation ANN can predict the heat transfer characteristics of
nanofluid very quickly compared to standard CFD method.
Abstract: Thousands of organisations store important and
confidential information related to them, their customers, and their
business partners in databases all across the world. The stored data
ranges from less sensitive (e.g. first name, last name, date of birth) to
more sensitive data (e.g. password, pin code, and credit card
information). Losing data, disclosing confidential information or
even changing the value of data are the severe damages that
Structured Query Language injection (SQLi) attack can cause on a
given database. It is a code injection technique where malicious SQL
statements are inserted into a given SQL database by simply using a
web browser. In this paper, we propose an effective pattern
recognition neural network model for detection and classification of
SQLi attacks. The proposed model is built from three main elements
of: a Uniform Resource Locator (URL) generator in order to generate
thousands of malicious and benign URLs, a URL classifier in order
to: 1) classify each generated URL to either a benign URL or a
malicious URL and 2) classify the malicious URLs into different
SQLi attack categories, and a NN model in order to: 1) detect either a
given URL is a malicious URL or a benign URL and 2) identify the
type of SQLi attack for each malicious URL. The model is first
trained and then evaluated by employing thousands of benign and
malicious URLs. The results of the experiments are presented in
order to demonstrate the effectiveness of the proposed approach.
Abstract: The purpose of the paper is to estimate the US small
wind turbines market potential and forecast the small wind turbines
sales in the US. The forecasting method is based on the application of
the Bass model and the generalized Bass model of innovations
diffusion under replacement purchases. In the work an exponential
distribution is used for modeling of replacement purchases. Only one
parameter of such distribution is determined by average lifetime of
small wind turbines. The identification of the model parameters is
based on nonlinear regression analysis on the basis of the annual
sales statistics which has been published by the American Wind
Energy Association (AWEA) since 2001 up to 2012. The estimation
of the US average market potential of small wind turbines (for
adoption purchases) without account of price changes is 57080
(confidence interval from 49294 to 64866 at P = 0.95) under average
lifetime of wind turbines 15 years, and 62402 (confidence interval
from 54154 to 70648 at P = 0.95) under average lifetime of wind
turbines 20 years. In the first case the explained variance is 90,7%,
while in the second - 91,8%. The effect of the wind turbines price
changes on their sales was estimated using generalized Bass model.
This required a price forecast. To do this, the polynomial regression
function, which is based on the Berkeley Lab statistics, was used. The
estimation of the US average market potential of small wind turbines
(for adoption purchases) in that case is 42542 (confidence interval
from 32863 to 52221 at P = 0.95) under average lifetime of wind
turbines 15 years, and 47426 (confidence interval from 36092 to
58760 at P = 0.95) under average lifetime of wind turbines 20 years.
In the first case the explained variance is 95,3%, while in the second
– 95,3%.