Abstract: The advances in location-based data collection
technologies such as GPS, RFID etc. and the rapid reduction of their
costs provide us with a huge and continuously increasing amount of
data about movement of vehicles, people and goods in an urban area.
This explosive growth of geospatially-referenced data has far
outpaced the planner-s ability to utilize and transform the data into
insightful information thus creating an adverse impact on the return
on the investment made to collect and manage this data. Addressing
this pressing need, we designed and developed DIVAD, a dynamic
and interactive visual analytics dashboard to allow city planners to
explore and analyze city-s transportation data to gain valuable
insights about city-s traffic flow and transportation requirements. We
demonstrate the potential of DIVAD through the use of interactive
choropleth and hexagon binning maps to explore and analyze large
taxi-transportation data of Singapore for different geographic and
time zones.
Abstract: Titanium alloys like Ti-6Al-2Sn-4Zr-6Mo (Ti-
6246) are widely used in aerospace applications. Component
manufacturing, however, is difficult and expensive as their
machinability is extremely poor. A thorough understanding of the
chip formation process is needed to improve related metal cutting
operations.In the current study, orthogonal cutting experiments have
been performed and theresulting chips were analyzed by optical
microscopy and scanning electron microscopy.Chips from aTi-
6246ingot were produced at different cutting speeds and cutting
depths. During the experiments, depending of the cutting conditions,
continuous or segmented chips were formed. Narrow, highly
deformed and grain oriented zones, the so-called shear zone,
separated individual segments. Different material properties have
been measured in the shear zones and the segments.
Abstract: In this paper, the effects of the restoring force device on the response of a space frame structure resting on sliding type of bearing with a restoring force device is studied. The NS component of the El - Centro earthquake and harmonic ground acceleration is considered for earthquake excitation. The structure is modeled by considering six-degrees of freedom (three translations and three rotations) at each node. The sliding support is modeled as a fictitious spring with two horizontal degrees of freedom. The response quantities considered for the study are the top floor acceleration, base shear, bending moment and base displacement. It is concluded from the study that the displacement of the structure reduces by the use of the restoring force device. Also, the peak values of acceleration, bending moment and base shear also decreases. The simulation results show the effectiveness of the developed and proposed method.
Abstract: Two approaches for model development of a smart acoustic box are suggested in this paper: the finite element (FE) approach and the subspace identification. Both approaches result in a state-space model, which can be used for obtaining the frequency responses and for the controller design. In order to validate the developed FE model and to perform the subspace identification, an experimental set-up with the acoustic box and dSPACE system was used. Experimentally obtained frequency responses show good agreement with the frequency responses obtained from the FE model and from the identified model.
Abstract: With the necessity of increased processing capacity with less energy consumption; power aware multiprocessor system has gained more attention in the recent future. One of the additional challenges that is to be solved in a multi-processor system when compared to uni-processor system is job allocation. This paper presents a novel task dependent job allocation algorithm: Energy centric- Allocation (Ec-A) and Rate Monotonic (RM) scheduling to minimize energy consumption in a multiprocessor system. A simulation analysis is carried out to verify the performance increase with reduction in energy consumption and required number of processors in the system.
Abstract: A cart-ball system is a challenging system from the
control engineering point of view. This is due to the nonlinearities,
multivariable, and non-minimum phase behavior present in this
system. This paper is concerned with the problem of modeling and
control of such system. The objective of control strategy is to place
the cart at a desired position while balancing the ball on the top of the
arc-shaped track fixed on the cart. A State-Feedback Controller
(SFC) with a pole-placement method will be designed in order to
control the system. At first, the mathematical model of a cart-ball
system in the state-space form is developed. Then, the linearization of
a model will be established in order to design a SFC. The integral
control strategy will be performed as to control the cart position of a
system. Simulation work is then performed using
MATLAB/SIMULINK software in order to study the performance of
SFC when applied to the system.
Abstract: Currently, there are many local area industrial networks
that can give guaranteed bandwidth to synchronous traffic, particularly
providing CBR channels (Constant Bit Rate), which allow
improved bandwidth management. Some of such networks operate
over Ethernet, delivering channels with enough capacity, specially
with compressors, to integrate multimedia traffic in industrial monitoring
and image processing applications with many sources. In
these industrial environments where a low latency is an essential
requirement, JPEG is an adequate compressing technique but it
generates VBR traffic (Variable Bit Rate). Transmitting VBR traffic
in CBR channels is inefficient and current solutions to this problem
significantly increase the latency or further degrade the quality. In
this paper an R(q) model is used which allows on-line calculation of
the JPEG quantification factor. We obtained increased quality, a lower
requirement for the CBR channel with reduced number of discarded
frames along with better use of the channel bandwidth.
Abstract: In an era of knowledge explosion, the growth of data
increases rapidly day by day. Since data storage is a limited resource,
how to reduce the data space in the process becomes a challenge issue.
Data compression provides a good solution which can lower the
required space. Data mining has many useful applications in recent
years because it can help users discover interesting knowledge in large
databases. However, existing compression algorithms are not
appropriate for data mining. In [1, 2], two different approaches were
proposed to compress databases and then perform the data mining
process. However, they all lack the ability to decompress the data to
their original state and improve the data mining performance. In this
research a new approach called Mining Merged Transactions with the
Quantification Table (M2TQT) was proposed to solve these problems.
M2TQT uses the relationship of transactions to merge related
transactions and builds a quantification table to prune the candidate
itemsets which are impossible to become frequent in order to improve
the performance of mining association rules. The experiments show
that M2TQT performs better than existing approaches.
Abstract: One major difficulty that faces developers of
concurrent and distributed software is analysis for concurrency based
faults like deadlocks. Petri nets are used extensively in the
verification of correctness of concurrent programs. ECATNets [2] are
a category of algebraic Petri nets based on a sound combination of
algebraic abstract types and high-level Petri nets. ECATNets have
'sound' and 'complete' semantics because of their integration in
rewriting logic [12] and its programming language Maude [13].
Rewriting logic is considered as one of very powerful logics in terms
of description, verification and programming of concurrent systems.
We proposed in [4] a method for translating Ada-95 tasking
programs to ECATNets formalism (Ada-ECATNet). In this paper,
we show that ECATNets formalism provides a more compact
translation for Ada programs compared to the other approaches based
on simple Petri nets or Colored Petri nets (CPNs). Such translation
doesn-t reduce only the size of program, but reduces also the number
of program states. We show also, how this compact Ada-ECATNet
may be reduced again by applying reduction rules on it. This double
reduction of Ada-ECATNet permits a considerable minimization of
the memory space and run time of corresponding Maude program.
Abstract: The objective of the research was to evaluate the
quality of milk pomade sweet – sherbet packed in different packaging
materials (Multibarrier 60, met.BOPET/PE, Aluthen), by several
packaging technologies – active and modified atmosphere (MAP)
(consisting of 100% CO2), and control – in air ambiance.
Experiments were carried out at the Faculty of Food Technology of
Latvia University of Agriculture. Samples were stored at the room
temperature +21±1 °C. The physiochemical properties – weight
losses, moisture, hardening, colour and changes in headspace
atmosphere concentration (CO2 and O2) of packs were analysed
before packaging and after 2, 4, 6, 8, 10 and 12 storage weeks.
Abstract: Safety, river environment, and sediment utilization are the elements of the target of sediment management. As a change in an element by sediment management, may affect the other two elements, and the priority among three elements depends on stakeholders. It is necessary to develop a method to evaluate the effect of sediment management on each element and an integrated evaluation method for socio-economic effect. In this study, taking Mount Merapi basin as an investigation field, the method for an active volcanic basin was developed. An integrated evaluation method for sediment management was discussed from a socio-economic point on safety, environment, and sediment utilization and a case study of sediment management was evaluated by means of this method. To evaluate the effect of sediment management, some parameters on safety, utilization, and environment have been introduced. From a utilization point of view, job opportunity, additional income of local people, and tax income to local government were used to evaluate the effectiveness of sediment management. The risk degree of river infrastructure was used to describe the effect of sediment management on a safety aspect. To evaluate the effects of sediment management on environment, the mean diameter of grain size distribution of riverbed surface was used. On the coordinate system designating these elements, the direction of change in basin condition by sediment management can be predicted, so that the most preferable sediment management can be decided. The results indicate that the cases of sediment management tend to give the negative impacts on sediment utilization. However, these sediment managements will give positive impacts on safety and environment condition. Evaluation result from a social-economic point of view shows that the case study of sediment management reduces job opportunity and additional income for inhabitants as well as tax income for government. Therefore, it is necessary to make another policy for creating job opportunity for inhabitants to support these sediment managements.
Abstract: We present a dual-band (Cellular & PCS) dual-path
zero-IF receiver for CDMA2000 diversity, monitoring and
simultaneous-GPS. The secondary path is a SAW-less diversity
CDMA receiver which can be also used for advanced features like
monitoring when supported with an additional external VCO. A GPS
receiver is integrated with its dedicated VCO allowing simultaneous
positioning during a cellular call. The circuit is implemented in a
0.25μm 40GHz-fT BiCMOS process and uses a HVQFN 56-pin
package. It consumes a maximum 300mW from a 2.8V supply in
dual-modes. The chip area is 12.8mm2.
Abstract: A Laboratory-scale packed bed reactor with microbial
cellulose as the biofilm carrier was used to investigate the
denitrification of high-strength nitrate wastewater with specific
emphasis on the effect the nitrogen loading rate and hydraulic
retention time. Ethanol was added as a carbon source for
denitrification. As a result of this investigation, it was found that up
to 500 mg/l feed nitrate concentration the present system is able to
produce an effluent with nitrate content below 10 ppm at 3 h
hydraulic retention time. The highest observed denitrification rate
was 4.57 kg NO3-N/ (m3 .d) at a nitrate load of 5.64 kg NO3-
N/(m3 .d), and removal efficiencies higher than 90% were obtained
for loads up to 4.2 kg NO3-N/(m3 .d). A mass relation between COD
consumed and NO3-N removed around 2.82 was observed. This
continuous-flow bioreactor proved an efficient denitrification system
with a relatively low retention time.
Abstract: The paper presents the method developed to assess
rating points of objects with qualitative indexes. The novelty of the
method lies in the fact that the authors use linguistic scales that allow
to formalize the values of the indexes with the help of fuzzy sets. As
a result it is possible to operate correctly with dissimilar indexes on
the unified basis and to get stable final results. The obtained rating
points are used in decision making based on fuzzy expert opinions.
Abstract: Nowadays companies strive to survive in a
competitive global environment. To speed up product
development/modifications, it is suggested to adopt a collaborative
product development approach. However, despite the advantages of
new IT improvements still many CAx systems work separately and
locally. Collaborative design and manufacture requires a product
information model that supports related CAx product data models. To
solve this problem many solutions are proposed, which the most
successful one is adopting the STEP standard as a product data model
to develop a collaborative CAx platform. However, the improvement
of the STEP-s Application Protocols (APs) over the time, huge
number of STEP AP-s and cc-s, the high costs of implementation,
costly process for conversion of older CAx software files to the STEP
neutral file format; and lack of STEP knowledge, that usually slows
down the implementation of the STEP standard in collaborative data
exchange, management and integration should be considered. In this
paper the requirements for a successful collaborative CAx system is
discussed. The STEP standard capability for product data integration
and its shortcomings as well as the dominant platforms for supporting
CAx collaboration management and product data integration are
reviewed. Finally a platform named LAYMOD to fulfil the
requirements of CAx collaborative environment and integrating the
product data is proposed. The platform is a layered platform to enable
global collaboration among different CAx software
packages/developers. It also adopts the STEP modular architecture
and the XML data structures to enable collaboration between CAx
software packages as well as overcoming the STEP standard
limitations. The architecture and procedures of LAYMOD platform
to manage collaboration and avoid contradicts in product data
integration are introduced.
Abstract: Through inward perceptions, we intuitively expect
distributed software development to increase the risks associated with
achieving cost, schedule, and quality goals. To compound this
problem, agile software development (ASD) insists one of the main
ingredients of its success is cohesive communication attributed to
collocation of the development team. The following study identified
the degree of communication richness needed to achieve comparable
software quality (reduce pre-release defects) between distributed and
collocated teams. This paper explores the relevancy of
communication richness in various development phases and its
impact on quality. Through examination of a large distributed agile
development project, this investigation seeks to understand the levels
of communication required within each ASD phase to produce
comparable quality results achieved by collocated teams. Obviously,
a multitude of factors affects the outcome of software projects.
However, within distributed agile software development teams, the
mode of communication is one of the critical components required to
achieve team cohesiveness and effectiveness. As such, this study
constructs a distributed agile communication model (DAC-M) for
potential application to similar distributed agile development efforts
using the measurement of the suitable level of communication. The
results of the study show that less rich communication methods, in
the appropriate phase, might be satisfactory to achieve equivalent
quality in distributed ASD efforts.
Abstract: One of the most important aspects expected from an
ERP system is to mange user\administrator manual documents
dynamically. Since an ERP package is frequently changed during its
implementation in customer sites, it is often needed to add new
documents and/or apply required changes to existing documents in
order to cover new or changed capabilities. The worse is that since
these changes occur continuously, the corresponding documents
should be updated dynamically; otherwise, implementing the ERP
package in the organization encounters serious risks. In this paper, we
propose a new architecture which is based on the agent oriented
vision and supplies the dynamic document generation expected from
ERP systems using several independent but cooperative agents.
Beside the dynamic document generation which is the main issue of
this paper, the presented architecture will address some aspects of
intelligence and learning capabilities existing in ERP.
Abstract: Adopting Zakowski-s upper approximation operator
C and lower approximation operator C, this paper investigates
granularity-wise separations in covering approximation spaces. Some
characterizations of granularity-wise separations are obtained by
means of Pawlak rough sets and some relations among granularitywise
separations are established, which makes it possible to research
covering approximation spaces by logical methods and mathematical
methods in computer science. Results of this paper give further
applications of Pawlak rough set theory in pattern recognition and
artificial intelligence.
Abstract: Swedish truck industry is investigating the possibility
for implementing the use of Compacted Graphite Iron (CGI) in their
heavy duty diesel engines. Compared to the alloyed gray iron used
today, CGI has superior mechanical properties but not as good
machinability. Another issue that needs to be addressed when
implementing CGI is the inhomogeneous microstructure when the
cast component has different section thicknesses, as in cylinder
blocks. Thinner sections results in finer pearlite, in the material, with
higher strength. Therefore an investigation on its influence on
machinability was needed. This paper focuses on the effect that
interlamellar distance in pearlite has on CGI machinability and
material physical properties. The effect of pearlite content and
nodularity is also examined. The results showed that interlamellar
distance in pearlite did not have as large effect on the material
physical properties or machinability as pearlite content. The paper
also shows the difficulties of obtaining a homogeneous
microstructure in inhomogeneous workpieces.
Abstract: The storage of thermal energy as a latent heat of phase
change material (PCM) has created considerable interest among
researchers in recent times. Here, an attempt is made to carry out
numerical investigations to analyze the performance of latent heat
storage units (LHSU) employing phase change material. The
mathematical model developed is based on an enthalpy formulation.
Freezing time of PCM packed in three different shaped containers
viz. rectangular, cylindrical and cylindrical shell is compared. The
model is validated with the results available in the literature. Results
show that for the same mass of PCM and surface area of heat
transfer, cylindrical shell container takes the least time for freezing
the PCM and this geometric effect is more pronounced with an
increase in the thickness of the shell than that of length of the shell.