Abstract: Firstly, research and development on RFID focuses on
manufacturing and retail sectors, because it can improve supply chain
efficiency. But, now a variety of field is considered the next research
area for Radio Frequency Identification (RFID). Although RFID is
infancy, RFID technology has great potential in power industry to
significantly reduce cost, and improve quality of power supply. To
complement the limitation of RFID, we adopt the WSN (Wireless
Sensor Network) technology. However, relevant experience is limited,
the challenge will be to derive requirement from business practice and
to determine whether it is possible or not. To explore this issue, we
conduct a case study on implementing power facility management
system using RFID/WSN in Korea Electric Power Corporation
(KEPCO). In this paper we describe requirement from power industry.
And we introduce design and implementation of the test bed.
Abstract: This paper presents a heuristic approach to solve the Generalized Assignment Problem (GAP) which is NP-hard. It is worth mentioning that many researches used to develop algorithms for identifying the redundant constraints and variables in linear programming model. Some of the algorithms are presented using intercept matrix of the constraints to identify redundant constraints and variables prior to the start of the solution process. Here a new heuristic approach based on the dominance property of the intercept matrix to find optimal or near optimal solution of the GAP is proposed. In this heuristic, redundant variables of the GAP are identified by applying the dominance property of the intercept matrix repeatedly. This heuristic approach is tested for 90 benchmark problems of sizes upto 4000, taken from OR-library and the results are compared with optimum solutions. Computational complexity is proved to be O(mn2) of solving GAP using this approach. The performance of our heuristic is compared with the best state-ofthe- art heuristic algorithms with respect to both the quality of the solutions. The encouraging results especially for relatively large size test problems indicate that this heuristic approach can successfully be used for finding good solutions for highly constrained NP-hard problems.
Abstract: A horizontal anaerobic digester was developed and
tested in pilot scale for Korean food waste with high water contents
(>80%). The hydrogen sulfide in the biogas was removed by a
biological desulfurization equipment integrated in the horizontal
digester. A mixer of the horizontal digester was designed to easily
remove the sediment in the bottom and scum layers on surface in the
digester. Experimental result for 120 days of operation of the pilot
plant showed a high removal efficiency of 81.2% for organic
substance and high stability during the whole operation period were
acquired. Also food waste was treated at high organic loading rates
over 4 kg•VS/m3∙day and a methane gas production rate of 0.62
m3/kg•VSremoved was accomplished.
The biological desulfurization equipment inside the horizontal
digester was proven to be an economic and effective method to reduce
the biogas desulfurization cost by removing hydrogen sulfide more
than 90% without external desulfurization equipments.
Abstract: In this study, a new procedure for inspecting damages on LNG storage tanks was proposed with the use of structural diagnostic techniques: i.e., nondestructive inspection techniques such as macrography, the hammer sounding test, the Schmidt hammer test, and the ultrasonic pulse velocity test, and destructive inspection techniques such as the compressive strength test, the chloride penetration test, and the carbonation test. From the analysis of all the test results, it was concluded that the LNG storage tank cover was in good condition. Such results were also compared with the Korean concrete standard specifications and design values. In addition, the remaining life of the LNG storage tank was estimated by using existing models. Based on the results, an LNG storage tank cover performance evaluation procedure was suggested.
Abstract: In this paper, design, fabrication and coupled
multifield analysis of hollow out-of-plane silicon microneedle array
with piezoelectrically actuated microfluidic device for transdermal
drug delivery (TDD) applications is presented. The fabrication
process of silicon microneedle array is first done by series of
combined isotropic and anisotropic etching processes using
inductively coupled plasma (ICP) etching technology. Then coupled
multifield analysis of MEMS based piezoelectrically actuated device
with integrated 2×2 silicon microneedle array is presented. To predict
the stress distribution and model fluid flow in coupled field analysis,
finite element (FE) and computational fluid dynamic (CFD) analysis
using ANSYS rather than analytical systems has been performed.
Static analysis and transient CFD analysis were performed to predict
the fluid flow through the microneedle array. The inlet pressure from
10 kPa to 150 kPa was considered for static CFD analysis. In the
lumen region fluid flow rate 3.2946 μL/min is obtained at 150 V for
2×2 microneedle array. In the present study the authors have
performed simulation of structural, piezoelectric and CFD analysis
on three dimensional model of the piezoelectrically actuated
mcirofluidic device integrated with 2×2 microneedle array.
Abstract: Wide applicability of concurrent programming
practices in developing various software applications leads to
different concurrency errors amongst which data race is the most
important. Java provides greatest support for concurrent
programming by introducing various concurrency packages. Aspect
oriented programming (AOP) is modern programming paradigm
facilitating the runtime interception of events of interest and can be
effectively used to handle the concurrency problems. AspectJ being
an aspect oriented extension to java facilitates the application of
concepts of AOP for data race detection. Volatile variables are
usually considered thread safe, but they can become the possible
candidates of data races if non-atomic operations are performed
concurrently upon them. Various data race detection algorithms have
been proposed in the past but this issue of volatility and atomicity is
still unaddressed. The aim of this research is to propose some
suggestions for incorporating certain conditions for data race
detection in java programs at the volatile fields by taking into account
support for atomicity in java concurrency packages and making use
of pointcuts. Two simple test programs will demonstrate the results
of research. The results are verified on two different Java
Development Kits (JDKs) for the purpose of comparison.
Abstract: The aerodynamic performances of vertical axis wind
turbines are highly affected by tip vortexes. In the present
work, different tip devices are considered and simulated against
a baseline rotor configuration, with the aim of identifying the
best tip architecture. Three different configurations are tested:
winglets, an elliptic termination and an aerodynamic bulkhead.
A comparative analysis on the most promising architectures is
conducted, focusing also on blade torque evolution during a full
revolution of the rotor blade. The most promising technology is
concluded to be a well designed winglet.
Abstract: Fuzzy sets theory affirmed that the linguistic value for
every contraries relation is complementary. It was stressed in the
intuitionistic fuzzy sets (IFS) that the conditions for contraries
relations, which are the fuzzy values, cannot be greater than one.
However, complementary in two contradict phenomena are not
always true. This paper proposes a new idea condition for conflicting
bifuzzy sets by relaxing the condition of intuitionistic fuzzy sets.
Here, we will critically forward examples using triangular fuzzy
number in formulating a new condition for conflicting bifuzzy sets
(CBFS). Evaluation of positive and negative in conflicting
phenomena were calculated concurrently by relaxing the condition in
IFS. The hypothetical illustration showed the applicability of the new
condition in CBFS for solving non-complement contraries
intuitionistic evaluation. This approach can be applied to any
decision making where conflicting is very much exist.
Abstract: According to development of communications and
web-based technologies in recent years, e-Learning has became very
important for everyone and is seen as one of most dynamic teaching
methods.
Grid computing is a pattern for increasing of computing power
and storage capacity of a system and is based on hardware and
software resources in a network with common purpose. In this article
we study grid architecture and describe its different layers. In this
way, we will analyze grid layered architecture. Then we will
introduce a new suitable architecture for e-Learning which is based
on grid network, and for this reason we call it Grid Learning
Architecture. Various sections and layers of suggested architecture
will be analyzed; especially grid middleware layer that has key role.
This layer is heart of grid learning architecture and, in fact,
regardless of this layer, e-Learning based on grid architecture will
not be feasible.
Abstract: In this paper a study on the vibration of thin
cylindrical shells with ring supports and made of functionally graded
materials (FGMs) composed of stainless steel and nickel is presented.
Material properties vary along the thickness direction of the shell
according to volume fraction power law. The cylindrical shells have
ring supports which are arbitrarily placed along the shell and impose
zero lateral deflections. The study is carried out based on third order
shear deformation shell theory (T.S.D.T). The analysis is carried out
using Hamilton-s principle. The governing equations of motion of
FGM cylindrical shells are derived based on shear deformation
theory. Results are presented on the frequency characteristics,
influence of ring support position and the influence of boundary
conditions. The present analysis is validated by comparing results
with those available in the literature.
Abstract: Frequent machine breakdowns, low plant availability and increased overtime are a great threat to a manufacturing plant as they increase operating costs of an industry. The main aim of this study was to improve Overall Equipment Effectiveness (OEE) at a manufacturing company through the implementation of innovative maintenance strategies. A case study approach was used. The paper focuses on improving the maintenance in a manufacturing set up using an innovative maintenance regime mix to improve overall equipment effectiveness. Interviews, reviewing documentation and historical records, direct and participatory observation were used as data collection methods during the research. Usually production is based on the total kilowatt of motors produced per day. The target kilowatt at 91% availability is 75 Kilowatts a day. Reduced demand and lack of raw materials particularly imported items are adversely affecting the manufacturing operations. The company had to reset its targets from the usual figure of 250 Kilowatt per day to mere 75 per day due to lower availability of machines as result of breakdowns as well as lack of raw materials. The price reductions and uncertainties as well as general machine breakdowns further lowered production. Some recommendations were given. For instance, employee empowerment in the company will enhance responsibility and authority to improve and totally eliminate the six big losses. If the maintenance department is to realise its proper function in a progressive, innovative industrial society, then its personnel must be continuously trained to meet current needs as well as future requirements. To make the maintenance planning system effective, it is essential to keep track of all the corrective maintenance jobs and preventive maintenance inspections. For large processing plants these cannot be handled manually. It was therefore recommended that the company implement (Computerised Maintenance Management System) CMMS.
Abstract: Our objective in this paper is to propose an approach
capable of clustering web messages. The clustering is carried out by
assigning, with a certain probability, texts written by the same web
user to the same cluster based on Stylometric features and using
fuzzy clustering algorithms. Focus in the present work is on
comparing the most popular algorithms in fuzzy clustering theory
namely, Fuzzy C-means, Possibilistic C-means and Fuzzy
Possibilistic C-Means.
Abstract: In this paper we study some numerical methods to solve a model one-dimensional convection–diffusion equation. The semi-discretisation of the space variable results into a system of ordinary differential equations and the solution of the latter involves the evaluation of a matrix exponent. Since the calculation of this term is computationally expensive, we study some methods based on Krylov subspace and on Restrictive Taylor series approximation respectively. We also consider the Chebyshev Pseudospectral collocation method to do the spatial discretisation and we present the numerical solution obtained by these methods.
Abstract: Optimal cultural site selection is one of the ways that
can lead to the promotion of citizenship culture in addition to
ensuring the health and leisure of city residents. This study examines
the social and cultural needs of the community and optimal cultural
site allocation and after identifying the problems and shortcomings,
provides a suitable model for finding the best location for these
centers where there is the greatest impact on the promotion of
citizenship culture. On the other hand, non-scientific methods cause
irreversible impacts to the urban environment and citizens. But
modern efficient methods can reduce these impacts. One of these
methods is using geographical information systems (GIS). In this
study, Analytical Hierarchy Process (AHP) method was used to
locate the optimal cultural site. In AHP, three principles
(decomposition), (comparative analysis), and (combining
preferences) are used. The objectives of this research include
providing optimal contexts for passing time and performing cultural
activities by Shiraz residents and also proposing construction of some
cultural sites in different areas of the city. The results of this study
show the correct positioning of cultural sites based on social needs of
citizens. Thus, considering the population parameters and radii
access, GIS and AHP model for locating cultural centers can meet
social needs of citizens.
Abstract: Indices summarizing community structure are used to
evaluate fundamental community ecology, species interaction,
biogeographical factors, and environmental stress. Some of these
indices are insensitive to gross community changes induced by
contaminants of pollution. Diversity indices and similarity indices are
reviewed considering their ecological application, both theoretical
and practical. For some useful indices, empirical equations are given
to calculate the expected maximum value of the indices to which the
observed values can be related at any combination of sample sizes at
the experimental sites. This paper examines the effects of sample size
and diversity on the expected values of diversity indices and
similarity indices, using various formulae. It has been shown that all
indices are strongly affected by sample size and diversity. In some
indices, this influence is greater than the others and an attempt has
been made to deal with these influences.
Abstract: Web services provide significant new benefits for SOAbased
applications, but they also expose significant new security
risks. There are huge number of WS security standards and
processes. At present, there is still a lack of a comprehensive
approach which offers a methodical development in the construction
of secure WS-based SOA. Thus, the main objective of this paper is
to address this needs, presenting a comprehensive method for Web
Services Security guaranty in SOA. The proposed method defines
three stages, Initial Security Analysis, Architectural Security
Guaranty and WS Security Standards Identification. These facilitate,
respectively, the definition and analysis of WS-specific security
requirements, the development of a WS-based security architecture
and the identification of the related WS security standards that the
security architecture must articulate in order to implement the
security services.
Abstract: The quality attributes and storage life of 'Jinhwang' mango fruit can be effectively maintained with 1-methylcyclopropene (1-MCP) application and/or chitosan coating. 'Jinhwang' mango fruit was treated with 5 μl l-1 1-MCP for 12 h, dipped with 0.5 % chitosan, 5 μl l-1 1-MCP combine with 0.5 % chitosan and untreated (control) then stored at 10oC. Mango treated with 1-MCP maintained firmness, sucrose and starch content. Chitosan coating delayed firmness loss, sucrose content and the fruit decay when compare with control. Application of 1-MCP combine with chitosan also delayed firmness loss, sucrose content and starch content during storage. Furthermore, chitosan coating and combine treatment prolonged storage life of mango up to 29 days after storage while 1-MCP extended to 28 days after storage. Therefore, using all application of chitosan coating or 1-MCP combine with chitosan or 1-MCP in mango at 10oC is a feasible technology for maintains quality and prolongs storage life in order to expand marketability and export options.
Abstract: One of the potential and effective ways of
storing thermal energy in buildings is the integration of brick with phase change materials (PCMs). This paper presents a two-dimensional model for simulating and analyzing of PCM
in order to minimize energy consumption in the buildings. The numerical approach has been used with the real weather data of a selected city of Iran (Tehran). Two kinds of brick integrated PCM are investigated and compared base on
outdoor weather conditions and the amount of energy
consumption. The results show a significant reduction in
maximum entering heat flux to building about 32.8%
depending on PCM quantity. The results are analyzed by
various temperature contour plots. The contour plots
illustrated the time dependent mechanism of entering heat flux for a brick integrated with PCM. Further analysis is developed to investigate the effect of PCM location on the inlet heat flux. The results demonstrated that to achieve maximum performance of PCM it is better to locate PCM near the outdoor.
Abstract: It is well known that surface enhancements play an important role in augmenting the thermal performance of flat plate solar collector. In this paper, an attempt is made to explain in a comparative way the effect of surface geometry of solar collector having dimple geometry with that of a flat plate solar collector of the same size. A CFD analysis was carried out for the two cases, subjected to a constant heat flux of 600W/m2 and 1000W/m2. It can be inferred from the study that the absorber plate temperature shows a rise of average surface temperature of about 50C for the dimple solar collector when compared to a flat plate solar collector. Most importantly, the average exit water temperature shows a marked improvement of about 5.50C for a dimple solar collector as compared to that of a flat plate solar collector.
Abstract: Capital structure is one of the most important financial
decisions in corporate financing strategy. It involves the choice of
debt and equity level in financing a company-s operations. This study
aims to investigate whether the capital structure choice of Malaysian
electrical and electronic manufacturing companies that are listed in
the Bursa Malaysia can be explained by factors that have been found
by most studies as dominant determinants of capital structure
(company size, profitability, asset tangibility, liquidity and growth).
Using debt ratio as the proxy for capital structure and applying
pooled ordinary least square multiple regression estimation, the
results showed that on average, Malaysian electrical and electronic
manufacturing companies used less debt in funding their business
operations. The findings also showed that size and asset tangibility
has a significant positive relationship with debt level, while liquidity
has a negative significant relationship with leverage.