Abstract: This paper develops driver reaction-time models for
car-following analysis based on human factors. The reaction time
was classified as brake-reaction time (BRT) and
acceleration/deceleration reaction time (ADRT). The BRT occurs
when the lead vehicle is barking and its brake light is on, while the
ADRT occurs when the driver reacts to adjust his/her speed using the
gas pedal only. The study evaluates the effect of driver
characteristics and traffic kinematic conditions on the driver reaction
time in a car-following environment. The kinematic conditions
introduced urgency and expectancy based on the braking behaviour
of the lead vehicle at different speeds and spacing. The kinematic
conditions were used for evaluating the BRT and are classified as
normal, surprised, and stationary. Data were collected on a driving
simulator integrated into a real car and included the BRT and ADRT
(as dependent variables) and driver-s age, gender, driving experience,
driving intensity (driving hours per week), vehicle speed, and
spacing (as independent variables). The results showed that there was
a significant difference in the BRT at normal, surprised, and
stationary scenarios and supported the hypothesis that both urgency
and expectancy had significant effects on BRT. Driver-s age, gender,
speed, and spacing were found to be significant variables for the
BRT in all scenarios. The results also showed that driver-s age and
gender were significant variables for the ADRT. The research
presented in this paper is part of a larger project to develop a driversensitive
in-vehicle rear-end collision warning system.
Abstract: Power-line networks are widely used today for broadband data transmission. However, due to multipaths within the broadband power line communication (BPLC) systems owing to stochastic changes in the network load impedances, branches, etc., network or channel capacity performances are affected. This paper attempts to investigate the performance of typical medium voltage channels that uses Orthogonal Frequency Division Multiplexing (OFDM) techniques with Quadrature Amplitude Modulation (QAM) sub carriers. It has been observed that when the load impedances are different from line characteristic impedance channel performance decreases. Also as the number of branches in the link between the transmitter and receiver increases a loss of 4dB/branch is found in the signal to noise ratio (SNR). The information presented in the paper could be useful for an appropriate design of the BPLC systems.
Abstract: In the planning point of view, it is essential to have
mode choice, due to the massive amount of incurred in transportation
systems. The intercity travellers in Libya have distinct features, as
against travellers from other countries, which includes cultural and
socioeconomic factors. Consequently, the goal of this study is to
recognize the behavior of intercity travel using disaggregate models,
for projecting the demand of nation-level intercity travel in Libya.
Multinomial Logit Model for all the intercity trips has been
formulated to examine the national-level intercity transportation in
Libya. The Multinomial logit model was calibrated using nationwide
revealed preferences (RP) and stated preferences (SP) survey. The
model was developed for deference purpose of intercity trips (work,
social and recreational). The variables of the model have been
predicted based on maximum likelihood method. The data needed for
model development were obtained from all major intercity corridors
in Libya. The final sample size consisted of 1300 interviews. About
two-thirds of these data were used for model calibration, and the
remaining parts were used for model validation. This study, which is
the first of its kind in Libya, investigates the intercity traveler’s
mode-choice behavior. The intercity travel mode-choice model was
successfully calibrated and validated. The outcomes indicate that, the
overall model is effective and yields higher precision of estimation.
The proposed model is beneficial, due to the fact that, it is receptive
to a lot of variables, and can be employed to determine the impact of
modifications in the numerous characteristics on the need for various
travel modes. Estimations of the model might also be of valuable to
planners, who can estimate possibilities for various modes and
determine the impact of unique policy modifications on the need for
intercity travel.
Abstract: In this paper, we derive some algebraic identities on
right and left neighbors R(F) and L(F) of an indefinite binary
quadratic form F = F(x, y) = ax2 + bxy + cy2 of discriminant
Δ = b2 -4ac. We prove that the proper cycle of F can be given by
using its consecutive left neighbors. Also we construct a connection
between right and left neighbors of F.
Abstract: When studying electronics, hands-on experience is considered to be very valuable for a better understanding of the concepts of electricity and electronics. Students lacking sufficient time in the lab are often put at disadvantage. A way to overcome this, is by using interactive multimedia in a virtual environment. Instead of proposing another new ad-hoc simulator for e-learning, we propose in this paper an e-learning platform integrating the SPICE simulator as a web service. This enables to make use of all the functions of the de-facto standard simulator SPICE inelectronics when developing new simulations.
Abstract: Color categorization is shared among members in a
society. This allows communication of color, especially when using
natural language such as English. Hence sociable robot, to live
coexist with human in human society, must also have the shared
color categorization. To achieve this, many works have been done
relying on modeling of human color perception and mathematical
complexities. In contrast, in this work, the computer as brain of the
robot learns color categorization through interaction with humans
without much mathematical complexities.
Abstract: To satisfy the need of outfield tests of star sensors, a
method is put forward to construct the reference attitude benchmark.
Firstly, its basic principle is introduced; Then, all the separate
conversion matrixes are deduced, which include: the conversion
matrix responsible for the transformation from the Earth Centered
Inertial frame i to the Earth-centered Earth-fixed frame w according to
the time of an atomic clock, the conversion matrix from frame w to the
geographic frame t, and the matrix from frame t to the platform frame
p, so the attitude matrix of the benchmark platform relative to the
frame i can be obtained using all the three matrixes as the
multiplicative factors; Next, the attitude matrix of the star sensor
relative to frame i is got when the mounting matrix from frame p to the
star sensor frame s is calibrated, and the reference attitude angles for
star sensor outfield tests can be calculated from the transformation
from frame i to frame s; Finally, the computer program is finished to
solve the reference attitudes, and the error curves are drawn about the
three axis attitude angles whose absolute maximum error is just 0.25ÔÇ│.
The analysis on each loop and the final simulating results manifest that
the method by precise timing to acquire the absolute reference attitude
is feasible for star sensor outfield tests.
Abstract: The problem of natural convection about a cone embedded in a porous medium at local Rayleigh numbers based on the boundary layer approximation and the Darcy-s law have been studied before. Similarity solutions for a full cone with the prescribed wall temperature or surface heat flux boundary conditions which is the power function of distance from the vertex of the inverted cone give us a third-order nonlinear differential equation. In this paper, an approximate method for solving higher-order ordinary differential equations is proposed. The approach is based on a rational Chebyshev Tau (RCT) method. The operational matrices of the derivative and product of rational Chebyshev (RC) functions are presented. These matrices together with the Tau method are utilized to reduce the solution of the higher-order ordinary differential equations to the solution of a system of algebraic equations. We also present the comparison of this work with others and show that the present method is applicable.
Abstract: The adsorption of simulated aqueous solution containing textile remazol reactive dye, namely Red 3BS by palm shell activated carbon (PSAC) as adsorbent was carried out using Response Surface Methodology (RSM). A Box-Behnken design in three most important operating variables; initial dye concentration, dosage of adsorbent and speed of impeller was employed for experimental design and optimization of results. The significance of independent variables and their interactions were tested by means of the analysis of variance (ANOVA) with 95% confidence limits. Model indicated that with the increasing of dosage and speed give the result of removal up to 90% with the capacity uptake more than 7 mg/g. High regression coefficient between the variables and the response (R-Sq = 93.9%) showed of good evaluation of experimental data by polynomial regression model.
Abstract: When choosing marketing strategies for international markets, one of the factors that should be considered is the cultural differences that exist among consumers in different countries. If the branding strategy has to be contextual and in tune with the culture, then the brand positioning variables has to interact, adapt and respond to the cultural variables in which the brand is operating. This study provides an overview of the relevance of culture in the development of an effective branding strategy in the international business environment. Hence, the main objective of this study is to provide a managerial framework for developing strategies for cross cultural brand management. The framework is useful because it incorporates the variables that are important in the competitiveness of fast food enterprises irrespective of their size. It provides practical, proactive and result oriented analysis that will help fast food firms augment their strategies in the international fast food markets. The proposed framework will enable managers understand the intricacies involved in branding in the global fast food industry and decrease the use of 'trial and error' when entering into unfamiliar markets.
Abstract: Chevron frames (Inverted-V-braced frames or Vbraced
frames) have seismic disadvantages, such as not good exhibit force redistribution capability and compression brace buckles
immediately. Researchers developed new design provisions on
increasing both the ductility and lateral resistance of these structures
in seismic areas. One of these new methods is adding zipper columns, as proposed by Khatib et al. (1988) [2]. Zipper columns are
vertical members connecting the intersection points of the braces
above the first floor. In this paper applicability of the suspended
zipper system to Seismic Rehabilitation of Steel Structures is investigated.
The models are 3-, 6-, 9-, and 12-story Inverted-V-braced frames.
In this case, it is assumed that the structures must be rehabilitated. For rehabilitation of structures, zipper column is used. The result of
researches showed that the suspended zipper system is effective in
case of 3-, 6-, and 9-story Inverted-V-braced frames and it would
increase lateral resistance of structure up to life safety level. But in
case of high-rise buildings (such as 12 story frame), it doesn-t show
good performance. For solving this problem, the braced bay can
consist of small “units" over the height of the entire structure, which each of them is a zipper-braced bay with a few stories. By using this
method the lateral resistance of 12 story Inverted-V-braced frames is increased up to safety life level.
Abstract: This article stands in the context of rural communities
in Brazil, where, like many others emerging countries, the
overwhelming increasing markets and the overcrowded cities are
leaving behind informal settlements based on obsolete agricultural
economies and techniques. The pilot project for the community of
Goiabeira reflects the attempt to imagine a development model that
privileges the actual improvement of living conditions, the education
and training, the social inclusion and participation of the dwellers of
rural communities. Through the inclusion of operative public space,
the aim is for them to become self-sustaining, encouraging the use of
local resources for appropriate architectural, ecological and energy
technologies and devices, that are efficient, affordable and foster
community participation, in the respect of the surrounding
environment.
Abstract: In this study, a reformer model simulation to use
refinery (Farashband refinery, Iran) waste natural gas. In the
petroleum and allied sectors where natural gas is being encountered
(in form of associated gas) without prior preparation for its positive
use, its combustion (which takes place in flares, an equipment through
which they are being disposed) has become a great problem because
of its associated environmental problems in form of gaseous emission.
The proposed model is used to product syngas from waste natural gas.
A detailed steady model described by a set of ordinary differential and
algebraic equations was developed to predict the behavior of the
overall process. The proposed steady reactor model was validated
against process data of a reformer synthesis plant recorded and a good
agreement was achieved. H2/CO ratio has important effect on Fischer-
Tropsch synthesis reactor product and we try to achieve this parameter
with best designing reformer reactor. We study different kind of
reformer reactors and then select auto thermal reforming process of
natural gas in a fixed bed reformer that adjustment H2/CO ratio with
CO2 and H2O injection. Finally a strategy was proposed for prevention
of extra natural gas to atmosphere.
Abstract: A one-step conservative level set method, combined with a global mass correction method, is developed in this study to simulate the incompressible two-phase flows. The present framework do not need to solve the conservative level set scheme at two separated steps, and the global mass can be exactly conserved. The present method is then more efficient than two-step conservative level set scheme. The dispersion-relation-preserving schemes are utilized for the advection terms. The pressure Poisson equation solver is applied to GPU computation using the pCDR library developed by National Center for High-Performance Computing, Taiwan. The SMP parallelization is used to accelerate the rest of calculations. Three benchmark problems were done for the performance evaluation. Good agreements with the referenced solutions are demonstrated for all the investigated problems.
Abstract: This paper investigates the activity of the
gastrocnemius (Gas) muscle in healthy subjects during salat (ruku-
position) and specific exercise [Unilateral Plantar Flexion Exercise
(UPFE)] using electromyography (EMG). Both lateral and medial
Gas muscles were assessed. A group of undergraduates aged between
19 to 25 years voluntarily participated in this study. The myoelectric
activity of the muscles were recorded and analyzed. The finding
indicated that there were contractions of the muscles during the salat
and exercise with almost same EMG-s level. From the result,
Wilcoxon-s Rank Sum test showed no significant difference between
ruku- and UPFE for both medial (p=0.082) and lateral (p=0.226) of
GAS muscles. Therefore, salat may be useful in strengthening
exercise and also in rehabilitation programs for lower limb activities.
Abstract: Self-propelled forage harvesters in the 850
horsepower range were tested over three years for fuel consumption,
throughput and quality of chop for corn silage. Cut length had a
significant effect on fuel consumption, throughput and some aspects
of chop quality. Measure cut length was often different than
theoretical length of cut. Where cut length was equivalent fuel
consumption and throughput were equivalent across brands.
Shortening cut length from 17 to 11mm increases fuel consumption
53 percent measured as Mg of silage harvested per gallon of fuel used
and a 42 percent decrease in capacity as tons of fresh material per
hour run time.
Abstract: Based on experimental data using accelerometry technology there was developed an analytical model that approximates human induced ground reaction forces in vertical, longitudinal and lateral directions ascending and descending the stairs. Proposed dynamic loading factors and corresponding phase shifts for the first five harmonics of continuous walking force history in case of stair ascend and descend. Into account is taken imperfectness of individual footfall forcing functions, differences between continuous walking force histories among individuals. There is proposed mean synthetic continuous walking force history that can be used in numerical simulations of human movement on the stairs.
Abstract: The presence of heavy metals in the environment
could constitute a hazard to food security and public health. These
can be accumulated in aquatic animals such as fish. Samples of four
popular brands of canned fish in the Iranian market (yellowfin tuna,
common Kilka, Kawakawa and longtail tuna) were analyzed for level
of Cr after wet digestion with acids using graphite furnace atomic
absorption spectrophotometry. The mean concentrations for Cr in the
different brands were: 2.57, 3.24, 3.16 and 1.65 μg/g for brands A, B,
C and D respectively. Significant differences were observed in the Cr
levels between all of the different brands of canned fish evaluated in
this study. The Cr concentrations for the varieties of canned fishes
were generally within the FAO/WHO, U.S. FDA and U.S. EPA
recommended limits for fish.
Abstract: The PAX6, a transcription factor, is essential for the morphogenesis of the eyes, brain, pituitary and pancreatic islets. In rodents, the loss of Pax6 function leads to central nervous system defects, anophthalmia, and nasal hypoplasia. The haplo-insufficiency of Pax6 causes microphthalmia, aggression and other behavioral abnormalities. It is also required in brain patterning and neuronal plasticity. In human, heterozygous mutation of Pax6 causes loss of iris [aniridia], mental retardation and glucose intolerance. The 3- deletion in Pax6 leads to autism and aniridia. The phenotypes are variable in peneterance and expressivity. However, mechanism of function and interaction of PAX6 with other proteins during development and associated disease are not clear. It is intended to explore interactors of PAX6 to elucidated biology of PAX6 function in the tissues where it is expressed and also in the central regulatory pathway. This report describes In-silico approaches to explore interacting proteins of PAX6. The models show several possible proteins interacting with PAX6 like MITF, SIX3, SOX2, SOX3, IPO13, TRIM, and OGT. Since the Pax6 is a critical transcriptional regulator and master control gene of eye and brain development it might be interacting with other protein involved in morphogenesis [TGIF, TGF, Ras etc]. It is also presumed that matricelluar proteins [SPARC, thrombospondin-1 and osteonectin etc] are likely to interact during transport and processing of PAX6 and are somewhere its cascade. The proteins involved in cell survival and cell proliferation can also not be ignored.
Abstract: Natural disasters, including earthquake, kill many people around the world every year. Society rescue actions, which start after the earthquake and are called LAST in abbreviation, include locating, access, stabilization and transportation. In the present article, we have studied the process of local accessibility to the injured and transporting them to health care centers. With regard the heavy traffic load due to earthquake, the destruction of connecting roads and bridges and the heavy debris in alleys and street, which put the lives of the injured and the people buried under the debris in danger, accelerating the rescue actions and facilitating the accessibilities are of great importance, obviously. Tehran, the capital of Iran, is among the crowded cities in the world and is the center of extensive economic, political, cultural and social activities. Tehran has a population of about 9.5 millions and because of the immigration of people from the surrounding cities. Furthermore, considering the fact that Tehran is located on two important and large faults, a 6 Richter magnitude earthquake in this city could lead to the greatest catastrophe during the entire human history. The present study is a kind of review and a major part of the required information for it, has been obtained from libraries all of the rescue vehicles around the world, including rescue helicopters, ambulances, fire fighting vehicles and rescue boats, and their applied technology, and also the robots specifically designed for the rescue system and the advantages and disadvantages of them, have been investigated. The studies show that there is a significant relationship between the rescue team-s arrival time at the incident zone and the number of saved people; so that, if the duration of burial under debris 30 minutes, the probability of survival is %99.3, after a day is %81, after 2days is %19 and after 5days is %7.4. The exiting transport systems all have some defects. If these defects are removed, more people could be saved each hour and the preparedness against natural disasters is increased. In this study, transport system has been designed for the rescue team and the injured; which could carry the rescue team to the incident zone and the injured to the health care centers. In addition, this system is able to fly in the air and move on the earth as well; so that the destruction of roads and the heavy traffic load could not prevent the rescue team from arriving early at the incident zone. The system also has the equipment required firebird for debris removing, optimum transport of the injured and first aid.