Abstract: It is well known that metallic particles reduce the
reliability of Gas-Insulated Substation (GIS) equipments by initiating
partial discharge (PDs) that can lead to breakdown and complete
failure of GIS. This paper investigates the characteristics of PDs
caused by metallic particle adhering to the solid spacer. The PD
detection and measurement were carried out by using IEC 60270
method with particles of different sizes and at different positions on
the spacer surface. The results show that a particle of certain size at
certain position possesses a unique PD characteristic as compared to
those caused by particles of different sizes and/or at different
positions. Therefore PD characteristics may be useful for the particle
size and position identification.
Abstract: This study employs the use of the fourth order
Numerov scheme to determine the eigenstates and eigenvalues of
particles, electrons in particular, in single and double delta function
potentials. For the single delta potential, it is found that the
eigenstates could only be attained by using specific potential depths.
The depth of the delta potential well has a value that varies depending
on the delta strength. These depths are used for each well on the
double delta function potential and the eigenvalues are determined.
There are two bound states found in the computation, one with a
symmetric eigenstate and another one which is antisymmetric.
Abstract: The Pads have unique values of thermophysical
properties (THP) having important contribution over heat transfer
into the PCB structure.
Materials with high thermal diffusivity (TD) rapidly adjust their
temperature to that of their surroundings, because the HT is quick in
compare to their volumetric heat capacity (VHC).
In the paper is presenting the diffusivity tests (ASTM E1461 flash
method) for PCBs with different core materials. In the experiments,
the multilayer structure of PCBA was taken into consideration, an
equivalent property referring to each of experimental structure be
practically measured.
Concerning to entire structure, the THP emphasize the major
contribution of substrate in establishing of reflow soldering process
(RSP) heat transfer necessities. This conclusion offer practical
solution for heat transfer time constant calculation as function of
thickness and substrate material diffusivity with an acceptable error
estimation.
Abstract: Phase error in communications systems degrades error
performance. In this paper, we present a simple approximation for the
average error probability of the binary phase shift keying (BPSK) in
the presence of phase error having a uniform distribution on arbitrary
intervals. For the simple approximation, we use symmetry and
periodicity of a sinusoidal function. Approximate result for the
average error probability is derived, and the performance is verified
through comparison with simulation result.
Abstract: The OTOP Entrepreneurship that used to create
substantial source of income for local Thai communities are now in a
stage of exigent matters that required assistances from public sectors
due to over Entrepreneurship of duplicative ideas, unable to adjust
costs and prices, lack of innovation, and inadequate of quality
control. Moreover, there is a repetitive problem of middlemen who
constantly corner the OTOP market. Local OTOP producers become
easy preys since they do not know how to add more values, how to
create and maintain their own brand name, and how to create proper
packaging and labeling. The suggested solutions to local OTOP
producers are to adopt modern management techniques, to find
knowhow to add more values to products and to unravel other
marketing problems. The objectives of this research are to study the
prevalent OTOP products management and to discover direction to
manage OTOP products to enhance the effectiveness of OTOP
Entrepreneurship in Nonthaburi Province, Thailand. There were 113
participants in this study. The research tools can be divided into two
parts: First part is done by questionnaire to find responses of the
prevalent OTOP Entrepreneurship management. Second part is the
use of focus group which is conducted to encapsulate ideas and local
wisdom. Data analysis is performed by using frequency, percentage,
mean, and standard deviation as well as the synthesis of several small
group discussions. The findings reveal that 1) Business Resources:
the quality of product is most important and the marketing of product
is least important. 2) Business Management: Leadership is most
important and raw material planning is least important. 3) Business
Readiness: Communication is most important and packaging is least
important. 4) Support from public sector: Certified from the
government is most important and source of raw material is the least
important.
Abstract: Cooling with sound is a physical phenomenon allowed by Thermo-Acoustics in which acoustic energy is transformed into a negative heat transfer, in other words: into cooling! Without needing any harmful gas, the transformation is environmentally friendly and can respond to many needs in terms of air conditioning, food refrigeration for domestic use, and cooling medical samples for example. To explore the possibilities of this cooling solution on a small scale, the TACS prototype has been designed, consisting of a low cost thermoacoustic refrigerant “pipe” able to lower the temperature by a few degrees. The obtained results are providing an interesting element for possible future of thermo-acoustic refrigeration.
Abstract: In this paper a computer system for electromagnetic
properties measurements is designed. The system employs Agilent
4294A precision impedance analyzer to measure the amplitude and
the phase of a signal applied over a tested biological tissue sample.
Measured by the developed computer system data could be used for
tissue characterization in wide frequency range from 40Hz to
110MHz. The computer system can interface with output devices
acquiring flexible testing process.
Abstract: This paper is devoted to predict laminar and turbulent
heating rates around blunt re-entry spacecraft at hypersonic
conditions. Heating calculation of a hypersonic body is normally
performed during the critical part of its flight trajectory. The
procedure is of an inverse method, where a shock wave is assumed,
and the body shape that supports this shock, as well as the flowfield
between the shock and body, are calculated. For simplicity the
normal momentum equation is replaced with a second order pressure
relation; this simplification significantly reduces computation time.
The geometries specified in this research, are parabola and ellipsoids
which may have conical after bodies. An excellent agreement is
observed between the results obtained in this paper and those
calculated by others- research. Since this method is much faster than
Navier-Stokes solutions, it can be used in preliminary design,
parametric study of hypersonic vehicles.
Abstract: Development of a Robust Supply Chain for Dynamic
Operating Environment as we move further into the twenty first
century, organisations are under increasing pressure to deliver a high
product variation at a reasonable cost without compromise in quality.
In a number of cases this will take the form of a customised or high
variety low volume manufacturing system that requires prudent
management of resources, among a number of functions, to achieve
competitive advantage. Purchasing and Supply Chain management is
one of such function and due to the substantial interaction with
external elements needs to be strategically managed. This requires a
number of primary and supporting tools that will enable the
appropriate decisions to be made rapidly. This capability is
especially vital in a dynamic environment as it provides a pivotal role
in increasing the profit margin of the product. The management of
this function can be challenging by itself and even more for Small
and Medium Enterprises (SMEs) due to the limited resources and
expertise available at their disposal.
This paper discusses the development of tools and concepts
towards effectively managing the purchasing and supply chain
function. The developed tools and concepts will provide a cost
effective way of managing this function within SMEs. The paper
further shows the use of these tools within Contechs, a manufacturer
of luxury boat interiors, and the associated benefits achieved as a
result of this implementation. Finally a generic framework towards
use in such environments is presented.
Abstract: Directive 2009/28/CE establishes, as obligatory objective, a share of renewable energies on energetic consumption of 20%, in European Union, in 2020 However, such European normative gives freedom to member states in the selection of the renewable promotion mechanism that allows them to obtain that objective. In this paper, we analyze the main characteristics of the promotion mechanisms of renewable energy used in the countries that shape the Electricity Iberian Market (Spain and Portugal) and the results in employment. The importance of these countries is given by the great increasing of the renewable energies which suppose a share higher than 30% of the overall generation in 2010. Therefore, this research paper can serve as the basis for the learning of other countries with regard to the main advantages that entail the use of a feed-in tariff system.
Abstract: In this paper, a novel road extraction method using Stationary Wavelet Transform is proposed. To detect road features from color aerial satellite imagery, Mexican hat Wavelet filters are used by applying the Stationary Wavelet Transform in a multiresolution, multi-scale, sense and forming the products of Wavelet coefficients at a different scales to locate and identify road features at a few scales. In addition, the shifting of road features locations is considered through multiple scales for robust road extraction in the asymmetry road feature profiles. From the experimental results, the proposed method leads to a useful technique to form the basis of road feature extraction. Also, the method is general and can be applied to other features in imagery.
Abstract: This paper describes a computer model of Quantum Field Theory (QFT), referred to in this paper as QTModel. After specifying the initial configuration for a QFT process (e.g. scattering) the model generates the possible applicable processes in terms of Feynman diagrams, the equations for the scattering matrix, and evaluates probability amplitudes for the scattering matrix and cross sections. The computations of probability amplitudes are performed numerically. The equations generated by QTModel are provided for demonstration purposes only. They are not directly used as the base for the computations of probability amplitudes. The computer model supports two modes for the computation of the probability amplitudes: (1) computation according to standard QFT, and (2) computation according to a proposed functional interpretation of quantum theory.
Abstract: This paper proposes and implements an core transform architecture, which is one of the major processes in HEVC video compression standard. The proposed core transform architecture is implemented with only adders and shifters instead of area-consuming multipliers. Shifters in the proposed core transform architecture are implemented in wires and multiplexers, which significantly reduces chip area. Also, it can process from 4×4 to 16×16 blocks with common hardware by reusing processing elements. Designed core transform architecture in 0.13um technology can process a 16×16 block with 2-D transform in 130 cycles, and its gate count is 101,015 gates.
Abstract: There are several ways of improving the performance of a vapor compression refrigeration cycle. Use of an ejector as expansion device is one of the alternative ways. The present paper aims at evaluate the performance improvement of a vapor compression refrigeration cycle under a wide range of operating conditions. A numerical model is developed and a parametric study of important parameters such as condensation (30-50°C) and evaporation temperatures (-20-5°C), nozzle and diffuser efficiencies (0.75-0.95), subcooling and superheating degrees (0-15K) are investigated. The model verification gives a good agreement with the literature data. The simulation results revealed that condensation temperature has the highest effect (129%) on the performance improvement ratio while superheating has the lowest one (6.2%). Among ejector efficiencies, the diffuser efficiency has a significant effect on the COP of ejector expansion refrigeration cycle. The COP improvement percentage decreases from 10.9% to 4.6% as subcooling degrees increases by 15K.
Abstract: Orthogonal Frequency Division Multiplexing (OFDM) is one of the techniques for high speed data rate communication with main consideration for 4G and 5G systems. In OFDM, there are several mapping schemes which provide a way of parallel transmission. In this paper, comparisons of mapping schemes used by some standards have been made and also has been discussed about the performance of the non-conventional modulation technique. The Comparisons of Bit Error Rate (BER) performances for conventional and non-conventional modulation schemes have been done using MATLAB software. Mentioned schemes used in OFDM system can be selected on the basis of the requirement of power or spectrum efficiency and BER analysis.
Abstract: Ant colony optimization is an ant algorithm framework that took inspiration from foraging behavior of ant colonies. Indeed, ACO algorithms use a chemical communication, represented by pheromone trails, to build good solutions. However, ants involve different communication channels to interact. Thus, this paper introduces the acoustic communication between ants while they are foraging. This process allows fine and local exploration of search space and permits optimal solution to be improved.
Abstract: The aim of the current work is to present a comparison among three popular optimization methods in the inverse elastostatics problem (IESP) of flaw detection within a solid. In more details, the performance of a simulated annealing, a Hooke & Jeeves and a sequential quadratic programming algorithm was studied in the test case of one circular flaw in a plate solved by both the boundary element (BEM) and the finite element method (FEM). The proposed optimization methods use a cost function that utilizes the displacements of the static response. The methods were ranked according to the required number of iterations to converge and to their ability to locate the global optimum. Hence, a clear impression regarding the performance of the aforementioned algorithms in flaw identification problems was obtained. Furthermore, the coupling of BEM or FEM with these optimization methods was investigated in order to track differences in their performance.
Abstract: The industrial process of the sugar cane crystallization produces a residual that still contains a lot of soluble sucrose and the objective of the factory is to improve its extraction. Therefore, there are substantial losses justifying the search for the optimization of the process. Crystallization process studied on the industrial site is based on the “three massecuites process". The third step of this process constitutes the final stage of exhaustion of the sucrose dissolved in the mother liquor. During the process of the third step of crystallization (Ccrystallization), the phase that is studied and whose control is to be improved, is the growing phase (crystal growth phase). The study of this process on the industrial site is a problem in its own. A control scheme is proposed to improve the standard PID control law used in the factory. An auto-tuning PID controller based on instantaneous linearization of a neural network is then proposed.
Abstract: This paper presents a wavelet transform and Support
Vector Machine (SVM) based algorithm for estimating fault location
on transmission lines. The Discrete wavelet transform (DWT) is used
for data pre-processing and this data are used for training and testing
SVM. Five types of mother wavelet are used for signal processing to
identify a suitable wavelet family that is more appropriate for use in
estimating fault location. The results demonstrated the ability of SVM
to generalize the situation from the provided patterns and to
accurately estimate the location of faults with varying fault resistance.
Abstract: Modeling of complex dynamic systems, which are
very complicated to establish mathematical models, requires new and
modern methodologies that will exploit the existing expert
knowledge, human experience and historical data. Fuzzy cognitive
maps are very suitable, simple, and powerful tools for simulation and
analysis of these kinds of dynamic systems. However, human experts
are subjective and can handle only relatively simple fuzzy cognitive
maps; therefore, there is a need of developing new approaches for an
automated generation of fuzzy cognitive maps using historical data.
In this study, a new learning algorithm, which is called Big Bang-Big
Crunch, is proposed for the first time in literature for an automated
generation of fuzzy cognitive maps from data. Two real-world
examples; namely a process control system and radiation therapy
process, and one synthetic model are used to emphasize the
effectiveness and usefulness of the proposed methodology.