Abstract: Experiments were conducted to characterize fire
properties of wood exposed to the certain external heat flux and
under variety of wood moisture content. Six kinds of Indonesian
wood: keruing, sono, cemara, kamper, pinus, and mahoni were
exposed to radiant heat from a conical heater, result in appearance of
a stable flame on the wood surface caused by spontaneous ignition. A
thermocouple K-type was used to measure the wood surface
temperature. Temperature histories were recorded throughout each
experiment at 1 s intervals using a TC-08. Data of first ignition time
and temperature, end ignition time and temperature, and charring rate
have been successfully collected. It was found that the ignition
temperature and charring rate depend on moisture content of wood.
Abstract: Querying a data source and routing data towards sink
becomes a serious challenge in static wireless sensor networks if sink
and/or data source are mobile. Many a times the event to be observed
either moves or spreads across wide area making maintenance of
continuous path between source and sink a challenge. Also, sink can
move while query is being issued or data is on its way towards sink.
In this paper, we extend our already proposed Grid Based Data
Dissemination (GBDD) scheme which is a virtual grid based
topology management scheme restricting impact of movement of
sink(s) and event(s) to some specific cells of a grid. This obviates the
need for frequent path modifications and hence maintains continuous
flow of data while minimizing the network energy consumptions.
Simulation experiments show significant improvements in network
energy savings and average packet delay for a packet to reach at sink.
Abstract: Vacuum membrane distillation (VMD) process can be
used for water purification or the desalination of salt water. The
process simply consists of a flat sheet hydrophobic micro porous
PTFE membrane and diaphragm vacuum pump without a condenser
for the water recovery or trap. The feed was used aqueous NaCl
solution. The VMD experiments were performed to evaluate the heat
and mass transfer coefficient of the boundary layer in a membrane
module. The only operating parameters are feed inlet temperature,
and feed flow rate were investigated. The permeate flux was strongly
affected by the feed inlet temperature, feed flow rate, and boundary
layer heat transfer coefficient. Since lowering the temperature
polarization coefficient is essential enhance the process performance
considerable and maximizing the heat transfer coefficient for
maximizes the mass flux of distillate water. In this paper, the results
of VMD experiments are used to measure the boundary layer heat
transfer coefficient, and the experimental results are used to reevaluate
the empirical constants in the Dittus- Boelter equation.
Abstract: In Grid computing, a data transfer protocol called
GridFTP has been widely used for efficiently transferring a large volume
of data. Currently, two versions of GridFTP protocols, GridFTP
version 1 (GridFTP v1) and GridFTP version 2 (GridFTP v2), have
been proposed in the GGF. GridFTP v2 supports several advanced
features such as data streaming, dynamic resource allocation, and
checksum transfer, by defining a transfer mode called X-block mode.
However, in the literature, effectiveness of GridFTP v2 has not been
fully investigated. In this paper, we therefore quantitatively evaluate
performance of GridFTP v1 and GridFTP v2 using mathematical
analysis and simulation experiments. We reveal the performance
limitation of GridFTP v1, and quantitatively show effectiveness of
GridFTP v2. Through several numerical examples, we show that by
utilizing the data streaming feature, the average file transfer time of
GridFTP v2 is significantly smaller than that of GridFTP v1.
Abstract: The paper outlines the relevance of computational
geometry within the design and production process of architecture.
Based on two case studies, the digital chain - from the initial formfinding
to the final realization of spatial concepts - is discussed in
relation to geometric principles. The association with the fascinating
complexity that can be found in nature and its underlying geometry
was the starting point for both projects presented in the paper. The
translation of abstract geometric principles into a three-dimensional
digital design model – realized in Rhinoceros – was followed by a
process of transformation and optimization of the initial shape that
integrated aesthetic, spatial and structural qualities as well as aspects
of material properties and conditions of production.
Abstract: The Pulsed Compression Reactor promises to be a
compact, economical and energy efficient alternative to conventional
chemical reactors.
In this article, the production of synthesis gas using the Pulsed
Compression Reactor is investigated. This is done experimentally as
well as with simulations. The experiments are done by means of a
single shot reactor, which replicates a representative, single
reciprocation of the Pulsed Compression Reactor with great control
over the reactant composition, reactor temperature and pressure and
temperature history. Simulations are done with a relatively simple
method, which uses different models for the chemistry and
thermodynamic properties of the species in the reactor. Simulation
results show very good agreement with the experimental data, and
give great insight into the reaction processes that occur within the
cycle.
Abstract: We studied the evolution of elliptic heavy SF6
gas cylinder surrounded by air when accelerated by a planar
Mach 1.25 shock. A multiple dynamics imaging technology has
been used to obtain one image of the experimental initial
conditions and five images of the time evolution of elliptic
cylinder. We compared the width and height of the circular and
two kinds of elliptic gas cylinders, and analyzed the vortex
strength of the elliptic ones. Simulations are in very good
agreement with the experiments, but due to the different initial
gas cylinder shapes, a certain difference of the initial density
peak and distribution exists between the circular and elliptic
gas cylinders, and the latter initial state is more sensitive and
more inenarrable.
Abstract: In wireless sensor networks,the mobile agent technology is used in data fusion. According to the node residual energy and the results of partial integration,we design the node clustering algorithm. Optimization of mobile agent in the routing within the cluster strategy for wireless sensor networks to further reduce the amount of data transfer. Through the experiments, using mobile agents in the integration process within the cluster can be reduced the path loss in some extent.
Abstract: A new approach for facial expressions recognition based on face context and adaptively weighted sub-pattern PCA (Aw-SpPCA) has been presented in this paper. The facial region and others part of the body have been segmented from the complex environment based on skin color model. An algorithm has been proposed to accurate detection of face region from the segmented image based on constant ratio of height and width of face (δ= 1.618). The paper also discusses on new concept to detect the eye and mouth position. The desired part of the face has been cropped to analysis the expression of a person. Unlike PCA based on a whole image pattern, Aw-SpPCA operates directly on its sub patterns partitioned from an original whole pattern and separately extracts features from them. Aw-SpPCA can adaptively compute the contributions of each part and a classification task in order to enhance the robustness to both expression and illumination variations. Experiments on single standard face with five types of facial expression database shows that the proposed method is competitive.
Abstract: There have been widespread applications of fluidized beds in industries which are related to the combination of gas-solid particles during the last decade. For instance, in order to crack the catalyses in petrochemical industries or as a drier in food industries. High capacity of fluidized bed in heat and mass transfer has made this device very popular. In order to achieve a higher efficiency of fluidized beds, a particular attention has been paid to beds with pulsating air flow. In this paper, a fluidized bed device with pulsating flow has been designed and constructed. Size of particles have been used during the test are in the range of 40 to 100μm. The purpose of this experimental test is to investigate the air flow regime, observe the particles- movement and measure the pressure loss along the bed. The effects of pulsation can be evaluated by comparing the results for both continuous and pulsating flow. Results of both situations are compared for various gas speeds. Moreover the above experiment is numerically simulated by using Fluent software and its numerical results are compared with the experimental results.
Abstract: This paper describes a method of modeling to model
shadow play puppet using sophisticated computer graphics techniques
available in OpenGL in order to allow interactive play in real-time
environment as well as producing realistic animation. This paper
proposes a novel real-time method is proposed for modeling of puppet
and its shadow image that allows interactive play of virtual shadow
play using texture mapping and blending techniques. Special effects
such as lighting and blurring effects for virtual shadow play
environment are also developed. Moreover, the use of geometric
transformations and hierarchical modeling facilitates interaction
among the different parts of the puppet during animation. Based on the
experiments and the survey that were carried out, the respondents
involved are very satisfied with the outcomes of these techniques.
Abstract: Developments in scientific and technical area cause to use new methods and techniques in education, as is the case in all fields. Especially, the internet contributes a variety of new methods to design virtual and real time laboratory applications in education. In this study, a real time virtual laboratory is designed and implemented for analog and digital communications laboratory experiments by using Lab VIEW program for Marmara University Electronics-Communication Department. In this application, students can access the virtual laboratory web site and perform their experiments without any limitation of time and location so as the students can observe the signals by changing the parameters of the experiment and evaluate the results.
Abstract: In 2002 an amendment to SOLAS opened for
lightweight material constructions in vessels if the same fire safety as
in steel constructions could be obtained. FISPAT (FIreSPread
Analysis Tool) is a computer application that simulates fire spread
and fault injection in cruise vessels and identifies fire sensitive areas.
It was developed to analyze cruise vessel designs and provides a
method to evaluate network layout and safety of cruise vessels. It
allows fast, reliable and deterministic exhaustive simulations and
presents the result in a graphical vessel model. By performing the
analysis iteratively while altering the cruise vessel design it can be
used along with fire chamber experiments to show that the
lightweight design can be as safe as a steel construction and that
SOLAS regulations are fulfilled.
Abstract: This paper considers the problem of finding low cost
chip set for a minimum cost partitioning of a large logic circuits. Chip
sets are selected from a given library. Each chip in the library has a
different price, area, and I/O pin. We propose a low cost chip set
selection algorithm. Inputs to the algorithm are a netlist and a chip
information in the library. Output is a list of chip sets satisfied with
area and maximum partitioning number and it is sorted by cost. The
algorithm finds the sorted list of chip sets from minimum cost to
maximum cost. We used MCNC benchmark circuits for experiments.
The experimental results show that all of chip sets found satisfy the
multiple partitioning constraints.
Abstract: Experiments have been carried out at sub-critical
Reynolds number to investigate free-to-roll motions induced by
forebody and/or wings complex flow on a 30° swept back nonslender
wings-slender body-model for static and dynamic (pitch-up)
cases. For the dynamic (pitch-up) case it has been observed that roll
amplitude decreases and lag increases with increase in pitching
speed. Decrease in roll amplitude with increase in pitch rate is
attributed to low disturbing rolling moment due to weaker interaction
between forebody and wing flow components. Asymmetric forebody
vortices dominate and control the roll motion of the model in
dynamic case when non-dimensional pitch rate ≥ 1x10-2.
Effectiveness of the active control scheme utilizing rotating nose with
artificial tip perturbation is observed to be low in the angle of attack
region where the complex flow over the wings has contributions from
both forebody and wings.
Abstract: Sparse representation which can represent high dimensional
data effectively has been successfully used in computer vision
and pattern recognition problems. However, it doesn-t consider the
label information of data samples. To overcome this limitation,
we develop a novel dimensionality reduction algorithm namely
dscriminatively regularized sparse subspace learning(DR-SSL) in this
paper. The proposed DR-SSL algorithm can not only make use of
the sparse representation to model the data, but also can effective
employ the label information to guide the procedure of dimensionality
reduction. In addition,the presented algorithm can effectively deal
with the out-of-sample problem.The experiments on gene-expression
data sets show that the proposed algorithm is an effective tool for
dimensionality reduction and gene-expression data classification.
Abstract: A hybrid Photovoltaic/Thermal (PV/T) solar system integrates photovoltaic and solar thermal technologies into one single solar energy device, with dual generation of electricity and heat energy. The aim of the present study is to evaluate the potential for introduction of the PV/T technology into Northern China. For this purpose, outdoor experiments were conducted on a prototype of a PV/T water-heating system. The annual thermal and electrical performances were investigated under the climatic conditions of Beijing. An economic analysis of the system was then carried out, followed by a sensitivity study. The analysis revealed that the hybrid system is not economically attractive with the current market and energy prices. However, considering the continuous commitment of the Chinese government towards policy development in the renewable energy sector, and technological improvements like the increasing cost-effectiveness of PV cells, PV/Thermal technology may become economically viable in the near future.
Abstract: Turkey has 72 % of total world boron reserves on the
basis of B2O3.Borates that is a refined form of boron minerals have a
wide range of applications. Zinc borates can be used as multifunctional
synergistic additives. The most important properties are
low solubility in water and high dehydration temperature. Zinc
borates dehydrate above 290°C and anhydrous zinc borate has
thermal resistance about 400°C. Zinc borates can be synthesized
using several methods such as hydrothermal and solid-state
processes. In this study, the solid-state method was applied between
500 and 800°C using the starting materials of ZnO and H3BO3 with
1:4 mole ratio. The reaction time was determined as 4 hours after
some preliminary experiments. After the synthesis, the crystal
structure and the morphology of the products were examined by XRay
Diffraction (XRD), Fourier Transform Infrared Spectroscopy
(FT-IR) and Raman Spectrometer. As a result the form of ZnB4O7
was synthesized with the highest crystal score at 800°C.
Abstract: This paper introduces a hand gesture recognition system to recognize real time gesture in unstrained environments. Efforts should be made to adapt computers to our natural means of communication: Speech and body language. A simple and fast algorithm using orientation histograms will be developed. It will recognize a subset of MAL static hand gestures. A pattern recognition system will be using a transforrn that converts an image into a feature vector, which will be compared with the feature vectors of a training set of gestures. The final system will be Perceptron implementation in MATLAB. This paper includes experiments of 33 hand postures and discusses the results. Experiments shows that the system can achieve a 90% recognition average rate and is suitable for real time applications.
Abstract: Two-dimensional Direct Numerical Simulation (DNS)
of high Schmidt number mass transfer in a convective flow environment
(Rayleigh-B'enard) is carried out and results are compared to
experimental data. A fourth-order accurate WENO-scheme has been
used for scalar transport in order to aim for a high accuracy in areas
of high concentration gradients. It was found that the typical spatial
distance between downward plumes of cold high concentration water
and the eddy size are in good agreement with experiments using a
combined PIV-LIF technique for simultaneous and spatially synoptic
measurements of 2D velocity and concentration fields.