Abstract: Durability of Membrane Electrode Assembly for
Proton Exchange Membrane Fuel Cells was evaluated in both steady
state and accelerated decay modes. Steady state mode was carried out
at constant current of 800mA/cm2 for 2500 hours using air as cathode
feed and pure hydrogen as anode feed. The degradation of the cell
voltage was 0.015V after such 2500 hrs operation. The degradation
rate was therefore calculated to be 6uV/hr. Continuously Vigorous
fluctuation of the cell voltage, which was switched between OCV and
0.2V, was employed for the accelerated decay mode. No obvious
change in performance of the MEA was observed after 10000 cycles
of such operation.
Abstract: This study, for its research subjects, uses patients who
had undergone total knee replacement surgery from the database of the
National Health Insurance Administration. Through the review of
literatures and the interviews with physicians, important factors are
selected after careful screening. Then using Cross Entropy Method,
Genetic Algorithm Logistic Regression, and Particle Swarm
Optimization, the weight of each factor is calculated and obtained. In
the meantime, Excel VBA and Case Based Reasoning are combined
and adopted to evaluate the system. Results show no significant
difference found through Genetic Algorithm Logistic Regression and
Particle Swarm Optimization with over 97% accuracy in both
methods. Both ROC areas are above 0.87. This study can provide
critical reference to medical personnel as clinical assessment to
effectively enhance medical care quality and efficiency, prevent
unnecessary waste, and provide practical advantages to resource
allocation to medical institutes.
Abstract: Due to today’s globalization as well as outsourcing
practices of the companies, the Supply Chain (SC) performances
have become more dependent on the efficient movement of material
among places that are geographically dispersed, where there is more
chance for disruptions. One such disruption is the quality and
delivery uncertainties of outsourcing. These uncertainties could lead
the products to be unsafe and, as is the case in a number of recent
examples, companies may have to end up in recalling their products.
As a result of these problems, there is a need to develop a
methodology for selecting suppliers globally in view of risks
associated with low quality and late delivery. Accordingly, we
developed a two-stage stochastic model that captures the risks
associated with uncertainty in quality and delivery as well as a
solution procedure for the model. The stochastic model developed
simultaneously optimizes supplier selection and purchase quantities
under price discounts over a time horizon. In particular, our target is
the study of global organizations with multiple sites and multiple
overseas suppliers, where the pricing is offered in suppliers’ local
currencies. Our proposed methodology is applied to a case study for a
US automotive company having two assembly plants and four
potential global suppliers to illustrate how the proposed model works
in practice.
Abstract: In recent years a new method of combination
treatment for cancer has been developed and studied that has led to
significant advancements in the field of cancer therapy. Hyperthermia
is a traditional therapy that, along with a creation of a medically
approved level of heat with the help of an alternating magnetic AC
current, results in the destruction of cancer cells by heat. This paper
gives details regarding the production of the spherical nanocomposite
PVA/γ-Fe2O3 in order to be used for medical purposes such as tumor
treatment by hyperthermia. To reach a suitable and evenly distributed
temperature, the nanocomposite with core-shell morphology and
spherical form within a 100 to 200 nanometer size was created using
phase separation emulsion, in which the magnetic nano-particles γ-
Fe2O3 with an average particle size of 20 nano-meters and with
different percentages of 0.2, 0.4, 0.5 and 0.6 were covered by
polyvinyl alcohol. The main concern in hyperthermia and heat
treatment is achieving desirable specific absorption rate (SAR) and
one of the most critical factors in SAR is particle size. In this project
all attempts has been done to reach minimal size and consequently
maximum SAR. The morphological analysis of the spherical
structure of the nanocomposite PVA/γ-Fe2O3 was achieved by SEM
analyses and the study of the chemical bonds created was made
possible by FTIR analysis. To investigate the manner of magnetic
nanocomposite particle size distribution a DLS experiment was
conducted. Moreover, to determine the magnetic behavior of the γ-
Fe2O3 particle and the nanocomposite PVA/γ-Fe2O3 in different
concentrations a VSM test was conducted. To sum up, creating
magnetic nanocomposites with a spherical morphology that would be
employed for drug loading opens doors to new approaches in
developing nanocomposites that provide efficient heat and a
controlled release of drug simultaneously inside the magnetic field,
which are among their positive characteristics that could significantly
improve the recovery process in patients.
Abstract: In this paper, we proposed a novel SCR (Silicon Controlled
Rectifier) - based ESD (Electrostatic Discharge) protection device for I/O
and power clamp. The proposed device has a higher holding voltage
characteristic than conventional SCR. These characteristics enable to have
latch-up immunity under normal operating conditions as well as superior full
chip ESD protection. The proposed device was analyzed to figure out
electrical characteristics and tolerance robustness in term of individual
design parameters (D1, D2, D3). They are investigated by using the
Synopsys TCAD simulator. As a result of simulation, holding voltage
increased with different design parameters. The holding voltage of the
proposed device changes from 3.3V to 7.9V. Also, N-Stack structure ESD
device with the high holding voltage is proposed. In the simulation results,
2-stack has holding voltage of 6.8V and 3-stack has holding voltage of
10.5V. The simulation results show that holding voltage of stacking
structure can be larger than the operation voltage of high-voltage
application.
Abstract: Biodiesel, as an alternative renewable fuel, has been
receiving increasing attention due to the limited supply of fossil fuels
and the increasing need for energy. Microalgae are promising source
for lipids, which can be converted to biodiesel. The biodiesel
production from microalgae lipids using lipase catalyzed reaction in
supercritical CO2 medium has several advantages over conventional
production processes. However, identifying the optimum microalgae
lipid extraction and transesterification conditions is still a challenge.
In this study, the quality of biodiesel produced from lipids extracted
from Scenedesmus sp. and their enzymatic transesterification using
supercritical carbon dioxide have been investigated. At the optimum
conditions, the highest biodiesel production yield was found to be
82%. The fuel properties of the produced biodiesel, without any
separation step, at optimum reaction condition, were determined and
compared to ASTM standards. The properties were found to comply
with the limits, and showed a low glycerol content, without any
separation step.
Abstract: Adopting Most Advantageous Tender (MAT) for the
government procurement projects has become popular in Taiwan. As
time pass by, the problems of MAT has appeared gradually. People
condemn two points that are the result might be manipulated by a
single committee member’s partiality and how to make a fair decision
when the winner has two or more. Arrow’s Impossibility Theorem
proposed that the best scoring method should meet the four reasonable
criteria. According to these four criteria this paper constructed an
“Illegitimate Scores Checking Scheme” for a scoring method and used
the scheme to find out the illegitimate of the current evaluation method
of MAT. This paper also proposed a new scoring method that is called
the “Standardizing Overall Evaluated Score Method”. This method
makes each committee member’s influence tend to be identical. Thus,
the committee members can scoring freely according to their partiality
without losing the fairness. Finally, it was examined by a large-scale
simulation, and the experiment revealed that the it improved the
problem of dictatorship and perfectly avoided the situation of cyclical
majorities, simultaneously. This result verified that the Standardizing
Overall Evaluated Score Method is better than any current evaluation
method of MAT.
Abstract: This paper presents an application of a “Systematic
Soft Domain Driven Design Framework” as a soft systems approach
to domain-driven design of information systems development. The
framework use SSM as a guiding methodology within which we have
embedded a sequence of design tasks based on the UML leading to
the implementation of a software system using the Naked Objects
framework. This framework have been used in action research
projects that have involved the investigation and modelling of
business processes using object-oriented domain models and the
implementation of software systems based on those domain models.
Within this framework, Soft Systems Methodology (SSM) is used as
a guiding methodology to explore the problem situation and to
develop the domain model using UML for the given business
domain. The framework is proposed and evaluated in our previous
works, and a real case study “Information Retrieval System for
academic research” is used, in this paper, to show further practice and
evaluation of the framework in different business domain. We argue
that there are advantages from combining and using techniques from
different methodologies in this way for business domain modelling.
The framework is overviewed and justified as multimethodology
using Mingers multimethodology ideas.
Abstract: This paper proposed the comparison made between
Multi-Carrier Pulse Width Modulation, Sinusoidal Pulse Width
Modulation and Selective Harmonic Elimination Pulse Width
Modulation technique for minimization of Total Harmonic Distortion
in Cascaded H-Bridge Multi-Level Inverter. In Multicarrier Pulse
Width Modulation method by using Alternate Position of Disposition
scheme for switching pulse generation to Multi-Level Inverter.
Another carrier based approach; Sinusoidal Pulse Width Modulation
method is also implemented to define the switching pulse generation
system in the multi-level inverter. In Selective Harmonic Elimination
method using Genetic Algorithm and Particle Swarm Optimization
algorithm for define the required switching angles to eliminate low
order harmonics from the inverter output voltage waveform and
reduce the total harmonic distortion value. So, the results validate that
the Selective Harmonic Elimination Pulse Width Modulation method
does capably eliminate a great number of precise harmonics and
minimize the Total Harmonic Distortion value in output voltage
waveform in compared with Multi-Carrier Pulse Width Modulation
method, Sinusoidal Pulse Width Modulation method. In this paper,
comparison of simulation results shows that the Selective Harmonic
Elimination method can attain optimal harmonic minimization
solution better than Multi-Carrier Pulse Width Modulation method,
Sinusoidal Pulse Width Modulation method.
Abstract: In addition to environmental parameters like rain,
temperature diseases on crop is a major factor which affects
production quality & quantity of crop yield. Hence disease
management is a key issue in agriculture. For the management of
disease, it needs to be detected at early stage. So, treat it properly &
control spread of the disease. Now a day, it is possible to use the
images of diseased leaf to detect the type of disease by using image
processing techniques. This can be achieved by extracting features
from the images which can be further used with classification
algorithms or content based image retrieval systems. In this paper,
color image is used to extract the features such as mean and standard
deviation after the process of region cropping. The selected features
are taken from the cropped image with different image size samples.
Then, the extracted features are taken in to the account for
classification using Fuzzy Inference System (FIS).
Abstract: Riveting process is one of the important ways to keep
fastening the lap joints in aircraft structures. Failure of aircraft lap
joints directly depends on the stress field in the joint. An important
application of riveting process is in the construction of aircraft
fuselage structures. In this paper, a 3D finite element method is
carried out in order to optimize residual stress field in a riveted lap
joint and also to estimate its fatigue life. In continue, a number of
experiments are designed and analyzed using design of experiments
(DOE). Then, Taguchi method is used to select an optimized case
between different levels of each factor. Besides that, the factor which
affects the most on residual stress field is investigated. Such
optimized case provides the maximum residual stress field. Fatigue
life of the optimized joint is estimated by Paris-Erdogan law. Stress
intensity factors (SIFs) are calculated using both finite element
analysis and experimental formula. In addition, the effect of residual
stress field, geometry and secondary bending are considered in SIF
calculation. A good agreement is found between results of such
methods. Comparison between optimized fatigue life and fatigue life
of other joints has shown an improvement in the joint’s life.
Abstract: This paper represents the results of experimental work to investigate the suitability of a waste material (WM) for soft soil stabilisation. In addition, the effect of particle size distribution (PSD) of the waste material on its performance as a soil stabiliser was investigated. The WM used in this study is produced from the incineration processes in domestic energy power plant and it is available in two different grades of fineness (coarse waste material (CWM) and fine waste material (FWM)). An intermediate plasticity silty clayey soil with medium organic matter content has been used in this study. The suitability of the CWM and FWM to improve the physical and engineering properties of the selected soil was evaluated dependant on the results obtained from the consistency limits, compaction characteristics (optimum moisture content (OMC) and maximum dry density (MDD)); along with the unconfined compressive strength test (UCS). Different percentages of CWM were added to the soft soil (3, 6, 9, 12 and 15%) to produce various admixtures. Then the UCS test was carried out on specimens under different curing periods (zero, 7, 14, and 28 days) to find the optimum percentage of CWM. The optimum and other two percentages (either side of the optimum content) were used for FWM to evaluate the effect of the fineness of the WM on UCS of the stabilised soil. Results indicated that both types of the WM used in this study improved the physical properties of the soft soil where the index of plasticity (IP) was decreased significantly. IP was decreased from 21 to 13.64 and 13.10 with 12% of CWM and 15% of FWM respectively. The results of the unconfined compressive strength test indicated that 12% of CWM was the optimum and this percentage developed the UCS value from 202kPa to 500kPa for 28 days cured samples, which is equal, approximately 2.5 times the UCS value for untreated soil. Moreover, this percentage provided 1.4 times the value of UCS for stabilized soil-CWA by using FWM which recorded just under 700kPa after 28 days curing.
Abstract: Experimental investigations of the DC electric field effect on thermal decomposition of biomass, formation of the axial flow of volatiles (CO, H2, CxHy), mixing of volatiles with swirling airflow at low swirl intensity (S ≈ 0.2-0.35), their ignition and on formation of combustion dynamics are carried out with the aim to understand the mechanism of electric field influence on biomass gasification, combustion of volatiles and heat energy production. The DC electric field effect on combustion dynamics was studied by varying the positive bias voltage of the central electrode from 0.6 kV to 3 kV, whereas the ion current was limited to 2 mA. The results of experimental investigations confirm the field-enhanced biomass gasification with enhanced release of volatiles and the development of endothermic processes at the primary stage of thermochemical conversion of biomass determining the field-enhanced heat energy consumption with the correlating decrease of the flame temperature and heat energy production at this stage of flame formation. Further, the field-enhanced radial expansion of the flame reaction zone correlates with a more complete combustion of volatiles increasing the combustion efficiency by 3% and decreasing the mass fraction of CO, H2 and CxHy in the products, whereas by 10% increases the average volume fraction of CO2 and the heat energy production downstream the combustor increases by 5-10%
Abstract: In this study, three robust predicting methods, namely artificial neural network (ANN), adaptive neuro fuzzy inference system (ANFIS) and support vector machine (SVM) were used for computing the resonant frequency of A-shaped compact microstrip antennas (ACMAs) operating at UHF band. Firstly, the resonant frequencies of 144 ACMAs with various dimensions and electrical parameters were simulated with the help of IE3D™ based on method of moment (MoM). The ANN, ANFIS and SVM models for computing the resonant frequency were then built by considering the simulation data. 124 simulated ACMAs were utilized for training and the remaining 20 ACMAs were used for testing the ANN, ANFIS and SVM models. The performance of the ANN, ANFIS and SVM models are compared in the training and test process. The average percentage errors (APE) regarding the computed resonant frequencies for training of the ANN, ANFIS and SVM were obtained as 0.457%, 0.399% and 0.600%, respectively. The constructed models were then tested and APE values as 0.601% for ANN, 0.744% for ANFIS and 0.623% for SVM were achieved. The results obtained here show that ANN, ANFIS and SVM methods can be successfully applied to compute the resonant frequency of ACMAs, since they are useful and versatile methods that yield accurate results.
Abstract: This paper proposes a novel heuristic algorithm that aims to determine the best size and location of distributed generators in unbalanced distribution networks. The proposed heuristic algorithm can deal with the planning cases where power loss is to be optimized without violating the system practical constraints. The distributed generation units in the proposed algorithm is modeled as voltage controlled node with the flexibility to be converted to constant power factor node in case of reactive power limit violation. The proposed algorithm is implemented in MATLAB and tested on the IEEE 37 -node feeder. The results obtained show the effectiveness of the proposed algorithm.
Abstract: This paper reviews the model-based qualitative and
quantitative Operations Management research in the context of
Construction Supply Chain Management (CSCM). Construction
industry has been traditionally blamed for low productivity, cost and
time overruns, waste, high fragmentation and adversarial
relationships. The construction industry has been slower than other
industries to employ the Supply Chain Management (SCM) concept
and develop models that support the decision-making and planning.
However the last decade there is a distinct shift from a project-based
to a supply-based approach of construction management. CSCM
comes up as a new promising management tool of construction
operations and improves the performance of construction projects in
terms of cost, time and quality. Modeling the Construction Supply
Chain (CSC) offers the means to reap the benefits of SCM, make
informed decisions and gain competitive advantage. Different
modeling approaches and methodologies have been applied in the
multi-disciplinary and heterogeneous research field of CSCM. The
literature review reveals that a considerable percentage of the CSC
modeling research accommodates conceptual or process models
which present general management frameworks and do not relate to
acknowledged soft Operations Research methods. We particularly
focus on the model-based quantitative research and categorize the
CSCM models depending on their scope, objectives, modeling
approach, solution methods and software used. Although over the last
few years there has been clearly an increase of research papers on
quantitative CSC models, we identify that the relevant literature is
very fragmented with limited applications of simulation,
mathematical programming and simulation-based optimization. Most
applications are project-specific or study only parts of the supply
system. Thus, some complex interdependencies within construction
are neglected and the implementation of the integrated supply chain
management is hindered. We conclude this paper by giving future
research directions and emphasizing the need to develop optimization
models for integrated CSCM. We stress that CSC modeling needs a
multi-dimensional, system-wide and long-term perspective. Finally,
prior applications of SCM to other industries have to be taken into
account in order to model CSCs, but not without translating the
generic concepts to the context of construction industry.
Abstract: In this work, the Ictalurus punctatus species estimated
available physical habitat is compared with the estimated physical
habitat for the same but modified river reach, with the aim of creating
a linear park, along a length of 5 500 m.
To determine the effect of ecological park construction, on
physical habitat of the Lerma river stretch of study, first, the available
habitat for the Ictalurus punctatus species was estimated through the
simulation of the physical habitat, by using surveying, hydraulics,
and habitat information gotten at the river reach in its actual situation.
Second, it was estimated the available habitat for the above species,
upon the simulation of the physical habitat through the proposed
modification for the ecological park creation. Third, it is presented a
comparison between both scenarios in terms of available habitat
estimated for Ictalurus punctatus species, concluding that in cases of
adult and spawning life stages, changes in the channel to create an
ecological park would produce a considerable loss of potentially
usable habitat (PUH), while in the case of the juvenile life stage PUH
remains virtually unchanged, and in the case of life stage fry the PUH
would increase due to the presence of velocities and depths of lesser
magnitude, due to the presence of minor flow rates and lower volume
of the wet channel.
It is expected that habitat modification for linear park construction
may produce the lack of Ictalurus punktatus species conservation at
the river reach of the study.
Abstract: A pilot field study was conducted at the Jagjeetpur
Municipal Sewage treatment plant situated in the Haridwar town in
Uttarakhand state, India. The objectives of the present study were to
study the effect of treated wastewater on the production of various
paddy varieties (Sharbati, PR-114, PB-1, Menaka, PB1121 and PB
1509) and the emission of GHG gases (CO2, CH4 and N2O) as
compared to the same varieties grown in the control plots irrigated
with fresh water. Of late, the concept of water footprint assessment
has emerged, which explains enumeration of various types of water
footprints of an agricultural entity from its production to processing
stages. Paddy, the most water demanding staple crop of Uttarakhand
state, displayed a high green water footprint value of 2474.12 m3/
Ton. Most of the wastewater irrigated varieties displayed up to 6%
increase in production, except Menaka and PB-1121, which showed a
reduction in production (6% and 3% respectively), due to pest and
insect infestation. The treated wastewater was observed to be rich in
Nitrogen (55.94 mg/ml Nitrate), Phosphorus (54.24 mg/ml) and
Potassium (9.78 mg/ml), thus rejuvenating the soil quality and not
requiring any external nutritional supplements. A Percentage increase
of GHG gases of irrigation with treated municipal wastewater as
compared to control plots was observed as 0.4% - 8.6% (CH4), 1.1%
- 9.2% (CO2), and 0.07% - 5.8% (N2O). The variety, Sharbati,
displayed maximum production (5.5 ton/ha) and emerged as the most
resistant variety against pests and insects. The emission values of
CH4, CO2 and N2O were 729.31 mg/m2/d, 322.10 mg/m2/d and
400.21 mg/m2/d in water stagnant condition.
This study highlighted a successful possibility of reuse of
wastewater for non-potable purposes offering the potential for
exploiting this resource that can replace or reduce the existing use of
fresh water sources in agriculture sector.
Abstract: In this paper, the goal programming methodology for
solving multiple objective problem of the technological variants and
production plan optimization has been applied. The optimization
criteria are determined and the multiple objective linear programming
model for solving a problem of the technological variants and
production plan optimization is formed and solved. Then the obtained
results are analysed. The obtained results point out to the possibility
of efficient application of the goal programming methodology in
solving the problem of the technological variants and production plan
optimization. The paper points out on the advantages of the
application of the goal programming methodology compare to the
Surrogat Worth Trade-off method in solving this problem.
Abstract: As technology-based service industries grow
drastically worldwide; companies are recognizing the importance of
market preoccupancy and have made an effort to capture a large
market to gain the upper hand. To this end, a focus on patents can be
used to determine the properties of a technology, as well as to capture
advantages in technical skills, in comparison with the firm’s
competitors. However, technology-based services largely depend not
only on their technological value but also their economic value, due
to the recognized worth that is passed to a plurality of users. Thus, it
is important to determine whether there are any competitors in the
target areas and what services they provide in any field. Despite this
importance, little effort has been made to systematically benchmark
competitors in order to identify business opportunities. Thus, this
study aims to not only identify each position of technology-centered
service companies in complex market dynamics, but also to discover
new business opportunities. For this, we try to consider both
technology and market environments simultaneously by utilizing
patent data as a representative proxy for technology and trademark
dates as an index for a firm’s target goods and services. Theoretically,
this is one of the earliest attempts to combine patent data and
trademark data to analyze corporate strategies. In practice, the
research results are expected to be used as a decision criterion to
diagnose the economic value that companies can obtain by entering
the market, as well as the technological value to be passed onto their
customers. Thus, the proposed approach can be useful to support
effective technology and business strategies in a firm.