Abstract: The aim of the article is extending and developing
econometrics and network structure based methods which are able to
distinguish price manipulation in Tehran stock exchange. The
principal goal of the present study is to offer model for
approximating price manipulation in Tehran stock exchange. In order
to do so by applying separation method a sample consisting of 397
companies accepted at Tehran stock exchange were selected and
information related to their price and volume of trades during years
2001 until 2009 were collected and then through performing runs
test, skewness test and duration correlative test the selected
companies were divided into 2 sets of manipulated and non
manipulated companies. In the next stage by investigating
cumulative return process and volume of trades in manipulated
companies, the date of starting price manipulation was specified and
in this way the logit model, artificial neural network, multiple
discriminant analysis and by using information related to size of
company, clarity of information, ratio of P/E and liquidity of stock
one year prior price manipulation; a model for forecasting price
manipulation of stocks of companies present in Tehran stock
exchange were designed. At the end the power of forecasting models
were studied by using data of test set. Whereas the power of
forecasting logit model for test set was 92.1%, for artificial neural
network was 94.1% and multi audit analysis model was 90.2%;
therefore all of the 3 aforesaid models has high power to forecast
price manipulation and there is no considerable difference among
forecasting power of these 3 models.
Abstract: The use of Virtual Reality (VR) in schools and higher education is proliferating. Due to its interactive and animated features, it is regarded as a promising technology to increase students- spatial ability. Spatial ability is assumed to have a prominent role in science and engineering domains. However, research concerning individual differences such as spatial ability in the context of VR is still at its infancy. Moreover, empirical studies that focus on the features of VR to improve spatial ability are to date rare. Thus, this paper explores the possible educational values of VR in relation to spatial ability to call for more research concerning spatial ability in the context of VR based on studies in computerbased learning. It is believed that the incorporation of state-of-the-art VR technology for educational purposes should be justified by the enhanced benefits for the target learners.
Abstract: One of the major problems in genomic field is to perform sequence comparison on DNA and protein sequences. Executing sequence comparison on the DNA and protein data is a computationally intensive task. Sequence comparison is the basic step for all algorithms in protein sequences similarity. Parallel computing is an attractive solution to provide the computational power needed to speedup the lengthy process of the sequence comparison. Our main research is to enhance the protein sequence algorithm using dynamic programming method. In our approach, we parallelize the dynamic programming algorithm using multithreaded program to perform the sequence comparison and also developed a distributed protein database among many PCs using Remote Method Interface (RMI). As a result, we showed how different sizes of protein sequences data and computation of scoring matrix of these protein sequence on different number of processors affected the processing time and speed, as oppose to sequential processing.
Abstract: III-nitride quaternary InxAlyGa1-x-yN alloys have experienced considerable interest as potential materials for optoelectronic applications. Despite these interesting applications and the extensive efforts to understand their fundamental properties, research on its fundamental surface property, i.e., surface phonon polariton (SPP) has not yet been reported. In fact, the SPP properties have been shown to provide application for some photonic devices. Hence, there is an absolute need for thorough studies on the SPP properties of this material. In this work, theoretical study on the SPP modes in InAlGaN quaternary alloys are reported. Attention is focus on the wurtzite (α-) structure InxAlyGa1-x-yN semi-crystal with different In composition, x ranging from 0 to 0.10 and constant Al composition, y = 0.06. The SPP modes are obtained through the theoretical simulation by means of anisotropy model. The characteristics of SP dispersion curves are discussed. Accessible results in terms of the experimental point of view are also given. Finally, the results revealed that the SPP mode of α-InxAlyGa1-x-yN semiconductors exhibits two-mode behavior.
Abstract: The last decade has seen an early majority of people
The last decade, the role of the of the information communication
technologies has increased in improving the social and business life
of people. Today, it is recognized that game could contribute to
enhance virtual rehabilitation by better engaging patients. Our
research study aims to develop a game based system enhancing
cognitive and physical capabilities of elderly people. To this end, the
project aims to develop a low cost hand held system based on
existing game such as Wii, PSP, or Xbox. This paper discusses the
concepts and requirements for developing such game for elderly
people. Based on the requirement elicitation, we intend to develop a
prototype related to sport and dance activities.
Abstract: In this research relationship between to be smooth the
interest and output of accepted companies stock at negotiable paper
exchange of Tehran is studied. Static community capacity included
363 companies member of negotiable paper exchange of Tehran that
54 companies were, by considering research limitation, selected from
2004 to 2009. Needed data for model test in librarian method was
chosen from RAH AVARDE NOVIN informative banks, TADBIR
and collecting needed data was selected from Tehran negotiable
paper exchange archive. Given results show that in spite of belief
among people based on companies have more smooth interest have
more output, but resulted outcomes of test-done reveals that there is
no relation between smooth interest and stock output.
Abstract: Unstructured peer-to-peer networks are popular due to
its robustness and scalability. Query schemes that are being used in
unstructured peer-to-peer such as the flooding and interest-based
shortcuts suffer various problems such as using large communication
overhead long delay response. The use of routing indices has been a
popular approach for peer-to-peer query routing. It helps the query
routing processes to learn the routing based on the feedbacks
collected. In an unstructured network where there is no global
information available, efficient and low cost routing approach is
needed for routing efficiency.
In this paper, we propose a novel mechanism for query-feedback
oriented routing indices to achieve routing efficiency in unstructured
network at a minimal cost. The approach also applied information
retrieval technique to make sure the content of the query is
understandable and will make the routing process not just based to
the query hits but also related to the query content. Experiments have
shown that the proposed mechanism performs more efficient than
flood-based routing.
Abstract: From a long time age, human beings have chosen their
place of residence and comfort so that those places would have
relatively ideal natural and climatic conditions. For this reason, from
the beginning, the civilizations have been formed in the susceptible
natural regions such as Mesopotamia in Iran and Nile coasts in
Egypt. Also, the core of human density has been made in the form of
an oasis in the deserts.
Regarding the formation and combination of the native
architecture in different regions of Iran, we find that different
properties of these climates have affected frequently the formation of
cities and the architectural combinations of these regions. Thus, the
precise determinations of climatic areas and attaining the climatic
properties of different regions have a great deal of importance in
presenting appropriate and compatible-with-climate designs.
Abstract: This work develops a novel intelligent “model of dynamic decision-making" usingcell assemblies network architecture in robot's movement. The “model of dynamic decision-making" simulates human decision-making, and follows commands to make the correct decisions. The cell assemblies approach consisting of fLIF neurons was used to implement tasks for finding targets and avoiding obstacles. Experimental results show that the cell assemblies approach of can be employed to efficiently complete finding targets and avoiding obstacles tasks and can simulate the human thinking and the mode of information transactions.
Abstract: The pyrolysis characteristics and kinetics of seven marine biomass, which are fixed Enteromorpha clathrata, floating Enteromorpha clathrata, Ulva lactuca L., Zosterae Marinae L., Thallus Laminariae, Asparagus schoberioides kunth and Undaria pinnatifida (Harv.), were studied with thermogravimetric analysis method. Simultaneously, cornstalk, which is a grass biomass, and sawdust, which is a lignocellulosic biomass, were references. The basic pyrolysis characteristics were studied by using TG- DTG-DTA curves. The results showed that there were three stages (dehydration, dramatic weight loss and slow weight loss) during the whole pyrolysis process of samples. The Tmax of marine biomass was significantly lower than two kinds of terrestrial biomass. Zosterae Marinae L. had a relatively high stability of pyrolysis, but floating Enteromorpha clathrata had lowest stability of pyrolysis and a good combustion characteristics. The corresponding activation energy E and frequency factor A were obtained by Coats-Redfern method. It was found that the pyrolysis reaction mechanism functions of three kinds of biomass are different.
Abstract: This paper presents a new type of mechanism and trajectory planning strategy for bipedal walking robot. The newly designed mechanism is able to improve the performance of bipedal walking robot in terms of energy efficiency and weight reduction by utilizing minimum number of actuators. The usage of parallelogram mechanism eliminates the needs of having an extra actuator at the knee joint. This mechanism works together with the joint space trajectory planning in order to realize straight legged walking which cannot be achieved by conventional inverse kinematics trajectory planning due to the singularity. The effectiveness of the proposed strategy is confirmed by computer simulation results.
Abstract: As the world changes more rapidly, the demand for update information for resource management, environment monitoring, planning are increasing exponentially. Integration of Remote Sensing with GIS technology will significantly promote the ability for addressing these concerns. This paper presents an alternative way of update GIS applications using image processing and high resolution images. We show a method of high-resolution image segmentation using graphs and morphological operations, where a preprocessing step (watershed operation) is required. A morphological process is then applied using the opening and closing operations. After this segmentation we can extract significant cartographic elements such as urban areas, streets or green areas. The result of this segmentation and this extraction is then used to update GIS applications. Some examples are shown using aerial photography.
Abstract: Current practice of indigenous Mapping production based on GIS, are mostly produced by professional GIS personnel. Given such persons maintain control over data collection and authoring, it is possible to conceive errors due to misrepresentation or cognitive misunderstanding, causing map production inconsistencies. In order to avoid such issues, this research into tribal GIS interface focuses not on customizing interfaces for individual tribes, but rather generalizing the interface and features based on indigenous tribal user needs. The methods employed differs from the traditional expert top-down approach, and instead gaining deeper understanding into indigenous Mappings and user needs, prior to applying mapping techniques and feature development.
Abstract: The paper presents a comparative performance of the
models developed to predict 28 days compressive strengths using
neural network techniques for data taken from literature (ANN-I) and
data developed experimentally for SCC containing bottom ash as
partial replacement of fine aggregates (ANN-II). The data used in the
models are arranged in the format of six and eight input parameters
that cover the contents of cement, sand, coarse aggregate, fly ash as
partial replacement of cement, bottom ash as partial replacement of
sand, water and water/powder ratio, superplasticizer dosage and an
output parameter that is 28-days compressive strength and
compressive strengths at 7 days, 28 days, 90 days and 365 days,
respectively for ANN-I and ANN-II. The importance of different
input parameters is also given for predicting the strengths at various
ages using neural network. The model developed from literature data
could be easily extended to the experimental data, with bottom ash as
partial replacement of sand with some modifications.
Abstract: This study suggests how an order-receiving company
can avoid disclosing schedule information on unit tasks to the
order-placing company when carrying out a collaborative project on
the value chain in an order-oriented industry. Specifically, it suggests
methods for keeping schedule information confidential, and
categorizes potential situations by inter-task dependency. Lastly, an
approach to select the most optimal non-disclosure method is
discussed. With the methods for not disclosing work-related
information suggested in the study, order-receiving companies can
logically deal with political issues relating to the question of whether
or not to disclose information upon the execution of a collaborative
project in cooperation with an order-placing firm. Moreover,
order-placing companies can monitor undistorted information, while
respecting the legitimate rights of an order-receiving company.
Therefore, it is fair to say that the suggestions made in this study will
contribute to the smooth operation of collaborative intercompany
projects.
Abstract: Due to their high power-to-weight ratio and low cost, pneumatic actuators are attractive for robotics and automation applications; however, achieving fast and accurate control of their position have been known as a complex control problem. The paper presents a methodology for obtaining controllers that achieve high position accuracy and preserve the closed-loop characteristics over a broad operating range. Experimentation with a number of conventional (or "classical") three-term controllers shows that, as repeated operations accumulate, the characteristics of the pneumatic actuator change requiring frequent re-tuning of the controller parameters (PID gains). Furthermore, three-term controllers are found to perform poorly in recovering the closed-loop system after the application of load or other external disturbances. The key reason for these problems lies in the non-linear exchange of energy inside the cylinder relating, in particular, to the complex friction forces that develop on the piston-wall interface. In order to overcome this problem but still remain within the boundaries of classical control methods, we designed an auto selective classicaql controller so that the system performance would benefit from all three control gains (KP, Kd, Ki) according to system requirements and the characteristics of each type of controller. This challenging experimentation took place for consistent performance in the face of modelling imprecision and disturbances. In the work presented, a selective PID controller is presented for an experimental rig comprising an air cylinder driven by a variable-opening pneumatic valve and equipped with position and pressure sensors. The paper reports on tests carried out to investigate the capability of this specific controller to achieve consistent control performance under, repeated operations and other changes in operating conditions.
Abstract: Most of the collision warning systems currently
available in the automotive market are mainly designed to warn
against imminent rear-end and lane-changing collisions. No collision
warning system is commercially available to warn against imminent
turning collisions at intersections, especially for left-turn collisions
when a driver attempts to make a left-turn at either a signalized or
non-signalized intersection, conflicting with the path of other
approaching vehicles traveling on the opposite-direction traffic
stream. One of the major factors that lead to left-turn collisions is the
human error and misjudgment of the driver of the turning vehicle
when perceiving the speed and acceleration of other vehicles
traveling on the opposite-direction traffic stream; therefore, using a
properly-designed collision warning system will likely reduce, or
even eliminate, this type of collisions by reducing human error. This
paper introduces perceptual framework for a proposed collision
warning system that can detect imminent left-turn collisions at
intersections. The system utilizes a commercially-available detection
sensor (either a radar sensor or a laser detector) to detect approaching
vehicles traveling on the opposite-direction traffic stream and
calculate their speeds and acceleration rates to estimate the time-tocollision
and compare that time to the time required for the turning
vehicle to clear the intersection. When calculating the time required
for the turning vehicle to clear the intersection, consideration is given
to the perception-reaction time of the driver of the turning vehicle,
which is the time required by the driver to perceive the message
given by the warning system and react to it by engaging the throttle.
A regression model was developed to estimate perception-reaction
time based on age and gender of the driver of the host vehicle.
Desired acceleration rate selected by the driver of the turning vehicle,
when making the left-turn movement, is another human factor that is
considered by the system. Another regression model was developed
to estimate the acceleration rate selected by the driver of the turning
vehicle based on driver-s age and gender as well as on the location
and speed of the nearest approaching vehicle along with the
maximum acceleration rate provided by the mechanical
characteristics of the turning vehicle. By comparing time-to-collision
with the time required for the turning vehicle to clear the intersection,
the system displays a message to the driver of the turning vehicle
when departure is safe. An application example is provided to
illustrate the logic algorithm of the proposed system.
Abstract: One of the important steps in a safety and risk management system is the economical evaluation of occupational accident and diseases costs in order to decrease accidents from reoccurring in the workplace. This study proposed a plausible method for calculating occupational accident costs and illnesses in work place. This method design for cost estimation takes into account both the personnel, organizational level as well as the community level especially intended for an Iranian work place. The research indicates that a using systematic method for calculating costs which also provides risk evaluation can help managers to plan correctly the investment in health and safety measures. Using this method is that not only is it comprehensive, easy and practical and could be applied in practice by a manager within a short period of time but it also shows the importance of accident costs as well as calculates the real cost of an accident and illnesses.
Abstract: The paper presents the service learning project titled
DicDucFac (idea-leadership-product), that was planned and
conducted by the team of information sciences students. It was
planned as a workshop dealing with the application of modern social
media (Facebook, YouTube, Gmail) for the purposes of selfpromotion,
free advertising via social networks and marketing own
ideas and/or products in the virtual world. The workshop was
organized for highly-skilled computer literate unemployed youth.
These youth, as final beneficiaries, will be able to apply what they
learned in this workshop to “the real world“, increasing their chances
for employment and self-employment. The results of the project
reveal that the basic, active-learning principles embodied in our
teaching approach allow students to learn more effectively and gain
essential life skills (from computer applications to teamwork) that
can only be learned by doing. It also shows that our students received
the essentials of professional ethics and citizenship through direct,
personal engagement in professional activities and the life of the
community.
Abstract: The Resource-Constrained Project Scheduling
Problem (RCPSP) is concerned with single-item or small batch
production where limited resources have to be allocated to dependent
activities over time. Over the past few decades, a lot of work has
been made with the use of optimal solution procedures for this basic
problem type and its extensions. Brucker and Knust[1] discuss, how
timetabling problems can be modeled as a RCPSP. Authors discuss
high school timetabling and university course timetabling problem as
an example. We have formulated two mathematical formulations of
course timetabling problem in a new way which are the prototype of
single-mode RCPSP. Our focus is to show, how course timetabling
problem can be transformed into RCPSP. We solve this
transformation model with genetic algorithm.