Abstract: The aim of this study is to analyze influence of
differences of heat insulation methods on indoor thermal environment and comfort of apartment buildings.
This study analyzes indoor thermal environment and comfort on units of apartment buildings using calculation software "THERB" and
compares three different kinds of heat insulation methods. Those are
outside insulation on outside walls, inside insulation on outside walls and interior insulation. In terms of indoor thermal environment, outside insulation is the best to stabilize room temperature. In winter, room temperature on
outside insulation after heating is higher than other and it is kept 3-5 degrees higher through all night. But the surface temperature with
outside insulation did not dramatically increase when heating was used, which was 3 to 5oC lower than the temperature with other
insulation. The PMV of interior insulation fall nearly range of comfort when the heating and cooling was use.
Abstract: A 1.2 V, 0.61 mA bias current, low noise amplifier
(LNA) suitable for low-power applications in the 2.4 GHz band is
presented. Circuit has been implemented, laid out and simulated using
a UMC 130 nm RF-CMOS process. The amplifier provides a 13.3 dB
power gain a noise figure NF< 2.28 dB and a 1-dB compression point
of -15.69 dBm, while dissipating 0.74 mW. Such performance make
this design suitable for wireless sensor networks applications such as
ZigBee.
Abstract: In this paper a novel method was presented for
evaluating the fabric pills using digital image processing techniques. This work provides a novel technique for
detecting pills and also measuring their heights, surfaces and
volumes. Surely, measuring the intensity of defects by human vision is an inaccurate method for quality control; as a result, this problem became a motivation for employing digital image processing techniques for detection of defects of fabric
surface. In the former works, the systems were just limited to measuring of the surface of defects, but in the presented
method the height and the volume of defects were also
measured, which leads to a more accurate quality control. An algorithm was developed to first, find pills and then measure their average intensity by using three criteria of height, surface
and volume. The results showed a meaningful relation
between the number of rotations and the quality of pilled fabrics.
Abstract: The main objectives of this paper are to measure
pollutants concentrations in the oil refinery area in Kuwait over three
periods during one year, obtain recent emission inventory for the
three refineries of Kuwait, use AERMOD and the emission inventory
to predict pollutants concentrations and distribution, compare model
predictions against measured data, and perform numerical
experiments to determine conditions at which emission rates and the
resulting pollutant dispersion is below maximum allowable limits.
Abstract: The 'wind-rain' house has a courtyard with glazed
roof, which allows more direct sunlight to come into indoor spaces
during the winter. The glazed roof can be partially opened or closed
and automatically controlled to provide natural ventilation in order to
adjust for indoor thermal conditions and the roof area can be shaded
by reflective insulation materials during the summer. Two field
studies for evaluating indoor thermal conditions of the two 'windrain'
houses have been carried out by author in 2009 and 2010.
Indoor and outdoor air temperature and relative humidity adjacent to
floor and ceiling of the two sample houses were continuously tested
at 15-minute intervals, 24 hours a day during the winter months.
Based on field study data, this study investigates relationships
between building design and indoor thermal condition of the 'windrain'
house to improve the future house design for building thermal
comfort and energy efficiency
Abstract: Effective employee selection is a critical component
of a successful organization. Many important criteria for personnel
selection such as decision-making ability, adaptability, ambition, and
self-organization are naturally vague and imprecise to evaluate. The
rough sets theory (RST) as a new mathematical approach to
vagueness and uncertainty is a very well suited tool to deal with
qualitative data and various decision problems. This paper provides
conceptual, descriptive, and simulation results, concentrating chiefly
on human resources and personnel selection factors. The current
research derives certain decision rules which are able to facilitate
personnel selection and identifies several significant features based
on an empirical study conducted in an IT company in Iran.
Abstract: Switched-mode converters play now a significant role in
modern society. Their operation are often crucial in various electrical
applications affecting the every day life. Therefore, the quality of
the converters needs to be reliably verified. Recent studies have
shown that the converters can be fully characterized by a set of
frequency responses which can be efficiently used to validate the
proper operation of the converters. Consequently, several methods
have been proposed to measure the frequency responses fast and
accurately. Most often correlation-based techniques have been applied.
The presented measurement methods are highly sensitive to
external errors and system nonlinearities. This fact has been often
forgotten and the necessary uncertainty analysis of the measured
responses has been neglected. This paper presents a simple approach
to analyze the noise and nonlinearities in the frequency-response
measurements of switched-mode converters. Coherence analysis is
applied to form a confidence interval characterizing the noise and
nonlinearities involved in the measurements. The presented method is
verified by practical measurements from a high-frequency switchedmode
converter.
Abstract: Mostly the systems are dealing with time varying
signals. The Power efficiency can be achieved by adapting the system
activity according to the input signal variations. In this context
an adaptive rate filtering technique, based on the level crossing sampling
is devised. It adapts the sampling frequency and the filter order
by following the input signal local variations. Thus, it correlates the
processing activity with the signal variations. Interpolation is required
in the proposed technique. A drastic reduction in the interpolation
error is achieved by employing the symmetry during the interpolation
process. Processing error of the proposed technique is
calculated. The computational complexity of the proposed filtering
technique is deduced and compared to the classical one. Results
promise a significant gain of the computational efficiency and hence
of the power consumption.
Abstract: The values of managers and employees in organizations are phenomena that have captured the interest of researchers at large. Despite this attention, there continues to be a lack of agreement on what values are and how they influence individuals, or how they are constituted in individuals- mind. In this article content-based approach is presented as alternative reference frame for exploring values. In content-based approach human thinking in different contexts is set at the focal point. Differences in valuations can be explained through the information contents of mental representations. In addition to the information contents, attention is devoted to those cognitive processes through which mental representations of values are constructed. Such informational contents are in decisive role for understanding human behavior. By applying content-based analysis to an examination of values as mental representations, it is possible to reach a deeper to the motivational foundation of behaviors, such as decision making in organizational procedures, through understanding the structure and meanings of specific values at play.
Abstract: Granular computing deals with representation of information in the form of some aggregates and related methods for transformation and analysis for problem solving. A granulation scheme based on clustering and Rough Set Theory is presented with focus on structured conceptualization of information has been presented in this paper. Experiments for the proposed method on four labeled data exhibit good result with reference to classification problem. The proposed granulation technique is semi-supervised imbibing global as well as local information granulation. To represent the results of the attribute oriented granulation a tree structure is proposed in this paper.
Abstract: Masonry cavity walls are loaded by wind pressure and vertical load from upper floors. These loads results in bending moments and compression forces in the ties connecting the outer and the inner wall in a cavity wall. Large cavity walls are furthermore loaded by differential movements from the temperature gradient between the outer and the inner wall, which results in critical increase of the bending moments in the ties. Since the ties are loaded by combined compression and moment forces, the loadbearing capacity is derived from instability equilibrium equations. Most of them are iterative, since exact instability solutions are complex to derive, not to mention the extra complexity introducing dimensional instability from the temperature gradients. Using an inverse variable substitution and comparing an exact theory with an analytical instability solution a method to design tie-connectors in cavity walls was developed. The method takes into account constraint conditions limiting the free length of the wall tie, and the instability in case of pure compression which gives an optimal load bearing capacity. The model is illustrated with examples from praxis.
Abstract: Polystyrene particles of different sizes are optically
trapped with a gaussian beam from a He-Cd laser operating at 442
nm. The particles are observed to exhibit luminescence after a certain
trapping time followed by an escape from the optical trap. The
observed luminescence is explained in terms of the photodegradation
of the polystyrene backbone. It is speculated that these chemical
modifications also play a role for the escape of the particles from the
trap. Variations of the particle size and the laser power show that
these parameters have a great influence on the observed phenomena.
Abstract: The main focus of this paper is on the human induced
forces. Almost all existing force models for this type of load (defined
either in the time or frequency domain) are developed from the
assumption of perfect periodicity of the force and are based on force
measurements conducted on rigid (i.e. high frequency) surfaces. To
verify the different authors conclusions the vertical pressure
measurements invoked during the walking was performed, using
pressure gauges in various configurations. The obtained forces are
analyzed using Fourier transformation. This load is often decisive in
the design of footbridges. Design criteria and load models proposed
by widely used standards and other researchers were introduced and a
comparison was made.
Abstract: Numerous experimental tests for post-installed anchor systems drilled in hardened concrete were conducted in order to estimate pull-out and shear strength accounting for uncertainties such as torque ratios, embedment depths and different diameters in demands. In this study, the strength of the systems was significantly changed by the effect of those three uncertainties during pull-out experimental tests, whereas the shear strength of the systems was not affected by torque ratios. It was also shown that concrete cone failure or damage mechanism was generally investigated during and after pull-out tests and in shear strength tests, mostly the anchor systems were failed prior to failure of primary structural system. Furthermore, 3D finite element model for the anchor systems was created by ABAQUS for the numerical analysis. The verification of finite element model was identical till the failure points to the load-displacement relationship specified by the experimental tests.
Abstract: Corrugated wire mesh laminates (CWML) are a class
of engineered open cell structures that have potential for applications
in many areas including aerospace and biomedical engineering. Two
different methods of fabricating corrugated wire mesh laminates from
stainless steel, one using a high temperature Lithobraze alloy and the
other using a low temperature Eutectic solder for joining the
corrugated wire meshes are described herein. Their implementation is
demonstrated by manufacturing CWML samples of 304 and 316
stainless steel (SST). It is seen that due to the facility of employing
wire meshes of different densities and wire diameters, it is possible to
create CWML laminates with a wide range of effective densities. The
fabricated laminates are tested under uniaxial compression. The
variation of the compressive yield strength with relative density of the
CWML is compared to the theory developed by Gibson and Ashby for
open cell structures [22]. It is shown that the compressive strength of
the corrugated wire mesh laminates can be described using the same
equations by using an appropriate value for the linear coefficient in the
Gibson-Ashby model.
Abstract: Nylon 6-clay hybrid/neat nylon 6, sheath/core
bicomponent nanocomposite fibers containing 4 wt% of clay in
sheath section were melt spun at different take-up speeds. Their
orientation and crystalline structure were compared to those of neat
nylon 6 fibers. Birefringence measurements showed that the
orientation development in sheath and core parts of bicomponent
fibers was different. Crystallinity results showed that clay did not act
as a nucleating agent for bicomponent fibers. The neat nylon 6 fiber
had a smooth surface while striped pattern was appeared on the
surface of bicomponent fiber containing clay due to thermal
shrinkage of the core part.
Abstract: The present study deals with the modeling and simulation of flow through an annular reactor at different hydrodynamic conditions using computational fluid dynamics (CFD) to investigate the flow behavior. CFD modeling was utilized to predict velocity distribution and average velocity in the annular geometry. The results of CFD simulations were compared with the mathematically derived equations and already developed correlations for validation purposes. CFD modeling was found suitable for predicting the flow characteristics in annular geometry under laminar flow conditions. It was observed that CFD also provides local values of the parameters of interest in addition to the average values for the simulated geometry.
Abstract: This paper generalizes Yeh Lam-s shock model for
renewal shock arrivals and random threshold. Several interesting
statistical measures are explicitly obtained. A few special cases and
an optimal replacement problem are also discussed.
Abstract: In Lebanon, public construction projects are awarded
to the contractor submitting the lowest bid price based on a
competitive bidding process. The contractor has to make a strategic
decision in choosing the appropriate bid price that will offer a
satisfactory profit with a greater probability to win. A simulation
model for bid price decision making based on the lowest bid price
evaluation is developed. The model, built using Crystal Ball decisionengineering
software, considers two main factors affecting the
bidding process: the number of qualified bidders and the size of the
project. The validity of the model is tested on twelve separate
projects. The study also shows how to use the model to conduct risk
analysis and help any specific contractor to decide on his bid price
with associated certainty level in a scientific method.
Abstract: Compost manufacturing plants are one of units where
wastewater is produced in significantly large amounts. Wastewater
produced in these plants contains high amounts of substrate (organic
loads) and is classified as stringent waste which creates significant
pollution when discharged into the environment without treatment. A
compost production plant in the one of the Iran-s province treating
200 tons/day of waste is one of the most important environmental
pollutant operations in this zone. The main objectives of this paper
are to investigate the compost wastewater treatability in hybrid
anaerobic reactors with an upflow-downflow arrangement, to
determine the kinetic constants, and eventually to obtain an
appropriate mathematical model. After starting the hybrid anaerobic
reactor of the compost production plant, the average COD removal
rate efficiency was 95%.