Abstract: Friction-stir welding has received a huge interest in the last few years. The many advantages of this promising process have led researchers to present different theoretical and experimental explanation of the process. The way to quantitatively and qualitatively control the different parameters of the friction-stir welding process has not been paved. In this study, a refined energybased model that estimates the energy generated due to friction and plastic deformation is presented. The effect of the plastic deformation at low energy levels is significant and hence a scale factor is introduced to control its effect. The predicted heat energy and the obtained maximum temperature using our model are compared to the theoretical and experimental results available in the literature and a good agreement is obtained. The model is applied to AA6000 and AA7000 series.
Abstract: Managers as the key employees have a very important
role in maintaining the workforce performance which is critical to the
construction companies- success in the future. If motivated
employees start with motivated managers probably it would seem
plausible if the de-motivated ones start with de-motivated managers.
This study aims to analyze the importance of motivated managers to
their successes and construction companies- successes. In this study,
a quantitative method was used and the study area was in Medan,
North Sumatera. Questionnaire survey was distributed directly to
construction companies in Medan which are listed in the
Construction Services Development Board. A total of 60 managers
responded and the completed questionnaires were analyzed using the
descriptive analysis. The results indicated that the respondents
acknowledge the importance of motivation among themselves to the
projects and construction companies- success, implying that it is vital
to maintain the motivation and good performance of the workforce.
Abstract: Without uncertainty by applying external loads on
beams, bending is created. The created bending in I-beams, puts one
of the flanges in tension and the other one in compression. With increasing of bending, compression flange buckled and beam in out
of its plane direction twisted, this twisting well-known as Lateral Torsional Buckling. Providing bending moment varieties along the
beam, the critical moment is greater than the case its under pure bending. In other words, the value of bending gradient coefficient is
always greater than unite. In this article by the use of " ANSYS 10.0" software near 80 3-D finite element models developed for the
propose of analyzing beams` lateral torsional buckling and surveying influence of slenderness on beams' bending gradient coefficient.
Results show that, presented Cb coefficient via AISC is not correct for some of beams and value of this coefficient is smaller than what proposed by AISC. Therefore instead of using a constant Cb for each
case of loading , a function with two criterion for calculation of Cb coefficient for some cases is proposed.
Abstract: Starting with an analysis of the financial and
operational indicators that can be found in the specialised literature,
this study aims to contribute to improvements in the performance
measurement systems used when the unit of analysis is the
manufacturing plant. For this a search was done in the highest impact
Journals of Production and Operations Management and
Management Accounting , with the aim of determining the financial
and operational indicators used to evaluate performance when
Advanced Production Practices have been implemented, more
specifically when the practices implemented are Total Quality
Management, JIT/Lean Manufacturing and Total Productive
Maintenance. This has enabled us to obtain a classification of the two
types of indicators based on how much each is used. For the financial
indicators we have also prepared a proposal that can be adapted to
manufacturing plants- accounting features. In the near future we will
propose a model that links practices implementation with financial
and operational indicators and these two last with each other. We aim
to will test this model empirically with the data obtained in the High
Performance Manufacturing Project.
Abstract: This paper is concerned with propagation of thermoelastic longitudinal vibrations of an infinite circular cylinder, in the context of the linear theory of generalized thermoelasticity with two relaxation time parameters (Green and Lindsay theory). Three displacement potential functions are introduced to uncouple the equations of motion. The frequency equation, by using the traction free boundary conditions, is given in the form of a determinant involving Bessel functions. The roots of the frequency equation give the value of the characteristic circular frequency as function of the wave number. These roots, which correspond to various modes, are numerically computed and presented graphically for different values of the thermal relaxation times. It is found that the influences of the thermal relaxation times on the amplitudes of the elastic and thermal waves are remarkable. Also, it is shown in this study that the propagation of thermoelastic longitudinal vibrations based on the generalized thermoelasticity can differ significantly compared with the results under the classical formulation. A comparison of the results for the case with no thermal effects shows well agreement with some of the corresponding earlier results.
Abstract: Social cognitive theory explains the power to inaugurate change is determined by the mutual influence of personal proclivity and social factors which will shape ones- motivations and expectations. In construction industry, green concept offers an opportunity to leave a lighter footprint on the environment. This opportunity, however, has not been fully grasped by many countries. As such, venturing into green construction for many practitioners would be their maiden experience. Decision to venture into new practice such as green construction will be influenced by certain drivers. This paper explores these drivers which is further expanded into motivational factors and later becomes the platform upon which expectation for green construction stands. This theoretical concept of motivation and expectations, which is adapted from social cognitive theory, focus on developers- view because of their crucial role in green application. This conceptual framework, which serves as the basis for further research, will benefit the industry as it elucidate cognitive angles to attract more new entrants to green business.
Abstract: DG application has received increasing attention during
recent years. The impact of DG on various aspects of distribution system
operation, such as reliability and energy loss, depend highly on DG
location in distribution feeder. Optimal DG placement is an important
subject which has not been fully discussed yet.
This paper presents an optimization method to determine optimal DG
placement, based on a cost/worth analysis approach. This method
considers technical and economical factors such as energy loss, load point
reliability indices and DG costs, and particularly, portability of DG. The
proposed method is applied to a test system and the impacts of different
parameters such as load growth rate and load forecast uncertainty (LFU)
on optimum DG location are studied.
Abstract: To model the human visual system (HVS) in the region of interest, we propose a new objective metric evaluation adapted to wavelet foveation-based image compression quality measurement, which exploits a foveation setup filter implementation technique in the DWT domain, based especially on the point and region of fixation of the human eye. This model is then used to predict the visible divergences between an original and compressed image with respect to this region field and yields an adapted and local measure error by removing all peripheral errors. The technique, which we call foveation wavelet visible difference prediction (FWVDP), is demonstrated on a number of noisy images all of which have the same local peak signal to noise ratio (PSNR), but visibly different errors. We show that the FWVDP reliably predicts the fixation areas of interest where error is masked, due to high image contrast, and the areas where the error is visible, due to low image contrast. The paper also suggests ways in which the FWVDP can be used to determine a visually optimal quantization strategy for foveation-based wavelet coefficients and to produce a quantitative local measure of image quality.
Abstract: Automated storage and retrieval systems (AS/RS)
become frequently used systems in warehouses. There has been a
transition from human based forklift applications to fast and safe
AS/RS applications in firm-s warehouse systems. In this study, basic
components and automation systems of the AS/RS are examined.
Proposed system's automation components and their tasks in the
system control algorithm were stated. According to this control
algorithm the control system structure was obtained.
Abstract: The present work was conducted for the synthesis of
nano size zerovalent iron (nZVI) and hexavalent chromium (Cr(VI))
removal as a highly toxic pollutant by using this nanoparticles. Batch
experiments were performed to investigate the effects of Cr(VI),
nZVI concentration, pH of solution and contact time variation on
the removal efficiency of Cr(VI). nZVI was synthesized by
reduction of ferric chloride using sodium borohydrid. SEM and
XRD examinations applied for determination of particle size and
characterization of produced nanoparticles. The results showed that
the removal efficiency decreased with Cr(VI) concentration and pH
of solution and increased with adsorbent dosage and contact time.
The Langmuir and Freundlich isotherm models were used for the
adsorption equilibrium data and the Langmuir isotherm model was
well fitted. Nanoparticle ZVI presented an outstanding ability to
remove Cr(VI) due to high surface area, low particle size and high
inherent activity.
Abstract: One of the basic concepts in marketing is the concept
of meeting customers- needs. Since customer satisfaction is essential
for lasting survival and development of a business, screening and
observing customer satisfaction and recognizing its underlying
factors must be one of the key activities of every business.
The purpose of this study is to recognize the drivers that effect
customer satisfaction in a business-to-business situation in order to
improve marketing activities. We conducted a survey in which 93
business customers of a manufacturer of Diesel Generator in Iran
participated and they talked about their ideas and satisfaction of
supplier-s services related to its products. We developed the measures
for drivers of satisfaction first by as investigative research (by means
of feedback from executives and customers of sponsoring firm). Then
based on these measures, we created a mail survey, and asked the
respondents to explain their opinion about the sponsoring firm which
was a supplier of diesel generator and similar products. Furthermore,
the survey required the participants to mention their functional areas
and their company features.
In Conclusion we found that there are three drivers for customer
satisfaction, which are reliability, information about product, and
commercial features. Buyers/users from different functional areas
attribute different degree of importance to the last two drivers. For
instance, people from buying and management areas believe that
commercial features are more important than information about
products. But people in engineering, maintenance and production
areas believe that having information about products is more
important than commercial aspects. Marketing experts should
consider the attribute of customers regarding information about the
product and commercial features to improve market share.
Abstract: We present a non standard Euclidean vehicle
routing problem adding a level of clustering, and we revisit the use
of self-organizing maps as a tool which naturally handles such
problems. We present how they can be used as a main operator
into an evolutionary algorithm to address two conflicting
objectives of route length and distance from customers to bus stops
minimization and to deal with capacity constraints. We apply the
approach to a real-life case of combined clustering and vehicle
routing for the transportation of the 780 employees of an
enterprise. Basing upon a geographic information system we
discuss the influence of road infrastructures on the solutions
generated.
Abstract: Saffron (Crocus sativus) is cultivated as spices,
medicinal and aromatic plant species. At autumn season, heavy
rainfall can cause flooding stress and inhibits growth of saffron. Thus
this research was conducted to study the effect of silver ion (as an
ethylene inhibitor) on growth of saffron under flooding conditions.
The corms of saffron were soaked with one concentration of nano
silver (0, 40, 80 or 120 ppm) and then planting under flooding stress
or non flooding stress conditions. Results showed that number of
roots, root length, root fresh and dry weight, leaves fresh and dry
weight were reduced by 10 day flooding stress. Soaking saffron
corms with 40 or 80 ppm concentration of nano silver rewarded the
effect of flooding stress on the root number, by increasing it.
Furthermore, 40 ppm of nano silver increased root length in stress.
Nano silver 80 ppm in flooding stress, increased leaves dry weight.
Abstract: Various methods of geofield parameters restoration (by algebraic polynoms; filters; rational fractions; interpolation splines; geostatistical methods – kriging; search methods of nearest points – inverse distance, minimum curvature, local – polynomial interpolation; neural networks) have been analyzed and some possible mistakes arising during geofield surface modeling have been presented.
Abstract: In this paper, the steady-state temperature of a sample 500 KW two rotor one stator Non-slotted axial flux permanent magnet motor is calculated using the finite element simulator software package. Due to the high temperature in various parts of the machine, especially at stator winding, a cooling system is designed for the motor and the temperature is recalculated. The results show that the temperature obtained for the parts is within the permissible range.
Abstract: Following the laser ablation studies leading to a
theory of nuclei confinement by a Debye layer mechanism, we
present here numerical evaluations for the known stable nuclei where
the Coulomb repulsion is included as a rather minor component
especially for lager nuclei. In this research paper the required
physical conditions for the formation and stability of nuclei
particularly endothermic nuclei with mass number greater than to
which is an open astrophysical question have been investigated.
Using the Debye layer mechanism, nuclear surface energy, Fermi
energy and coulomb repulsion energy it is possible to find conditions
under which the process of nucleation is permitted in early universe.
Our numerical calculations indicate that about 200 second after the
big bang at temperature of about 100 KeV and subrelativistic region
with nucleon density nearly equal to normal nuclear density namely,
10cm all endothermic and exothermic nuclei have been
formed.
Abstract: In this paper, the 1-D conduction-radiation problem is solved by the lattice Boltzmann method. The effects of various parameters such as the scattering albedo, the conduction–radiation parameter and the wall emissivity are studied. In order to check on the accuracy of the numerical technique employed for the solution of the considered problem, the present numerical code was validated with the published study. The found results are in good agreement with those published
Abstract: Safety Health and Environment Code of Practice (SHE
COP) was developed to help road transportation operators to manage
its operation in a systematic and safe manner. A study was conducted
to determine the effectiveness of SHE COP implementation during
non-OPS period. The objective of the study is to evaluate the
implementations of SHE COP among bus operators during wee hour
operations. The data was collected by completing a set of checklist
after observing the activities during pre departure, during the trip, and
upon arrival. The results show that there are seven widely practiced
SHE COP elements. 22% of the buses have average speed exceeding
the maximum permissible speed on the highways (90 km/h), with
13% of the buses were travelling at the speed of more than 100 km/h.
The statistical analysis shows that there is only one significant
association which relates speeding with prior presence of
enforcement officers.
Abstract: Dried soy protein hydrolysate powder was added to
the burger in order to enhance the oxidative stability as well as
decreases the microbial spoilage. The soybean bioactive compounds
(soy protein hydrolysate) as antioxidant and antimicrobial were added
at level of 1, 2 and 3 %.Chemical analysis and physical properties
were affected by protein hydrolysate addition. The TBA values were
significantly affected (P < 0.05) by the storage period and the level of
soy protein hydrolysate. All the tested soybean protein hydrolysate
additives showed strong antioxidant properties. Samples of soybean
protein hydrolysate showed the lowest (P < 0.05) TBA values at each
time of storage.
The counts of all determined microbiological indicators were
significantly (P < 0.05) affected by the addition of the soybean
protein hydrolysate. Decreasing trends of different extent were also
observed in samples of the treatments for total viable counts,
Coliform, Staphylococcus aureus, yeast and molds. Storage period
was being significantly (P < 0.05) affected on microbial counts in all
samples Staphylococcus aureus were the most sensitive microbe
followed by Coliform group of the sample containing protein
hydrolysate, while molds and yeast count showed a decreasing trend
but not significant (P < 0.05) until the end of the storage period
compared with control sample. Sensory attributes were also
performed, added protein hydrolysate exhibits beany flavor which
was clear about samples of 3% protein hydrolysate.
Abstract: In this paper, the torsion capacity of ultimate point on rectangular beams with spiral reinforcements in the torsion direction and its anti-direction are investigated. Therefore, models of above-mentioned beams have been numerically analyzed under various loads using ANSYS software. It was observed that, spirallyreinforced prismatic beam and beam with spiral links, show lower torsion capacity than beam with normal links also in anti-direction. The result is that the concrete regulations are violated in this case.