Abstract: Web usage mining has become a popular research
area, as a huge amount of data is available online. These data can be
used for several purposes, such as web personalization, web structure
enhancement, web navigation prediction etc. However, the raw log
files are not directly usable; they have to be preprocessed in order to
transform them into a suitable format for different data mining tasks.
One of the key issues in the preprocessing phase is to identify web
users. Identifying users based on web log files is not a
straightforward problem, thus various methods have been developed.
There are several difficulties that have to be overcome, such as client
side caching, changing and shared IP addresses and so on. This paper
presents three different methods for identifying web users. Two of
them are the most commonly used methods in web log mining
systems, whereas the third on is our novel approach that uses a
complex cookie-based method to identify web users. Furthermore we
also take steps towards identifying the individuals behind the
impersonal web users. To demonstrate the efficiency of the new
method we developed an implementation called Web Activity
Tracking (WAT) system that aims at a more precise distinction of
web users based on log data. We present some statistical analysis
created by the WAT on real data about the behavior of the Hungarian
web users and a comprehensive analysis and comparison of the three
methods
Abstract: This article illustrates a model selection management approach for virtual prototypes in interactive simulations. In those numerical simulations, the virtual prototype and its environment are modelled as a multiagent system, where every entity (prototype,human, etc.) is modelled as an agent. In particular, virtual prototyp ingagents that provide mathematical models of mechanical behaviour inform of computational methods are considered. This work argues that selection of an appropriate model in a changing environment,supported by models? characteristics, can be managed by the deter-mination a priori of specific exploitation and performance measures of virtual prototype models. As different models exist to represent a single phenomenon, it is not always possible to select the best one under all possible circumstances of the environment. Instead the most appropriate shall be selecting according to the use case. The proposed approach consists in identifying relevant metrics or indicators for each group of models (e.g. entity models, global model), formulate their qualification, analyse the performance, and apply the qualification criteria. Then, a model can be selected based on the performance prediction obtained from its qualification. The authors hope that this approach will not only help to inform engineers and researchers about another approach for selecting virtual prototype models, but also assist virtual prototype engineers in the systematic or automatic model selection.
Abstract: In this paper is study the possibility of successfully
implementing of hollow roller concept in order to minimize inertial
mass of the large bearings, with major results in diminution of the
material consumption, increasing of power efficiency (in wind power
station area), increasing of the durability and life duration of the large
bearings systems, noise reduction in working, resistance to
vibrations, an important diminution of losses by abrasion and
reduction of the working temperature. In this purpose was developed
an original solution through which are reduced mass, inertial forces
and moments of large bearings by using of hollow rollers. The
research was made by using the method of finite element analysis
applied on software type Solidworks - Nastran. Also, is study the
possibility of rapidly changing the manufacturing system of solid and
hollow cylindrical rollers.
Abstract: Periodic vortex shedding in pulsating flow inside wavy
channel and the effect it has on heat transfer are studied using the
finite volume method. A sinusoidally-varying component is superimposed
on a uniform flow inside a sinusoidal wavy channel and
the effects on the Nusselt number is analyzed. It was found that a
unique optimum value of the pulsation frequency, represented by the
Strouhal number, exists for Reynolds numbers ranging from 125 to
1000. Results suggest that the gain in heat transfer is related to the
process of vortex formation, movement about the troughs of the wavy
channel, and subsequent ejection/destruction through the converging
section. Heat transfer is the highest when the frequencies of the
pulsation and vortex formation approach being in-phase. Analysis of
Strouhal number effect on Nu over a period of pulsation substantiates
the proposed physical mechanism for enhancement. The effect of
changing the amplitude of pulsation is also presented over a period
of pulsation, showing a monotonic increase in heat transfer with
increasing amplitude. The 60% increase in Nusselt number suggests
that sinusoidal fluid pulsation can an effective method for enhancing
heat transfer in laminar, wavy-channel flows.
Abstract: When a high DC voltage is applied to a capacitor with
strongly asymmetrical electrodes, it generates a mechanical force that
affects the whole capacitor. This is caused by the motion of ions generated around the smaller of the two electrodes and their subsequent interaction with the surrounding medium. If one of the electrodes is heated, it changes the conditions around the capacitor
and influences the process of ionisation, thus changing the value of the generated force. This paper describes these changes and gives
reasons behind them. Further the experimental results are given as proof of the ionic mechanism of the phenomenon.
Abstract: In this paper, an efficient structural approach for
recognizing on-line handwritten digits is proposed. After reading
the digit from the user, the slope is estimated and normalized for
adjacent nodes. Based on the changing of signs of the slope values,
the primitives are identified and extracted. The names of these
primitives are represented by strings, and then a finite state
machine, which contains the grammars of the digits, is traced to
identify the digit. Finally, if there is any ambiguity, it will be
resolved. Experiments showed that this technique is flexible and
can achieve high recognition accuracy for the shapes of the digits
represented in this work.
Abstract: Chakri Maha Prasart Throne Hall is the important
Audience hall in Grand Palace, Bangkok, Thailand which was
established in the early reign of King Chulalongkorn (King Rama V)
in 1882. The Throne was designed with the distinguished architecture
by significant blending of Western and Thai Traditional styles under
the Thai Social changing in Colony Era and Thai traditional culture.
The western style was represented of modernization and civilization as
the other European countries. In the other hand, Thai traditional
architecture style with national emblem or Royal emblem was shown
the status and power of Thai King as the Thai believes and culture.
Abstract: This paper proposes a low-cost reconfigurable
architecture for AES algorithm. The proposed architecture separates
SubBytes and MixColumns into two parallel data path, and supports
different bit-width operation for this two data path. As a result, different number of S-box can be supported in this architecture. The
throughput and power consumption can be adjusted by changing the
number of S-box running in this design. Using the TSMC 0.18μm CMOS standard cell library, a very low-cost implementation of 7K
Gates is obtained under 182MHz frequency. The maximum throughput is 360Mbps while using 4 S-Box simultaneously, and the
minimum throughput is 114Mbps while only using 1 S-Box
Abstract: A novel typical day prediction model have been built and validated by the measured data of a grid-connected solar photovoltaic (PV) system in Macau. Unlike conventional statistical method used by previous study on PV systems which get results by averaging nearby continuous points, the present typical day statistical method obtain the value at every minute in a typical day by averaging discontinuous points at the same minute in different days. This typical day statistical method based on discontinuous point averaging makes it possible for us to obtain the Gaussian shape dynamical distributions for solar irradiance and output power in a yearly or monthly typical day. Based on the yearly typical day statistical analysis results, the maximum possible accumulated output energy in a year with on site climate conditions and the corresponding optimal PV system running time are obtained. Periodic Gaussian shape prediction models for solar irradiance, output energy and system energy efficiency have been built and their coefficients have been determined based on the yearly, maximum and minimum monthly typical day Gaussian distribution parameters, which are obtained from iterations for minimum Root Mean Squared Deviation (RMSD). With the present model, the dynamical effects due to time difference in a day are kept and the day to day uncertainty due to weather changing are smoothed but still included. The periodic Gaussian shape correlations for solar irradiance, output power and system energy efficiency have been compared favorably with data of the PV system in Macau and proved to be an improvement than previous models.
Abstract: This paper presents a novel control strategy of a threephase
four-wire Unified Power Quality (UPQC) for an improvement
in power quality. The UPQC is realized by integration of series and
shunt active power filters (APFs) sharing a common dc bus capacitor.
The shunt APF is realized using a thee-phase, four leg voltage source
inverter (VSI) and the series APF is realized using a three-phase,
three leg VSI. A control technique based on unit vector template
technique (UTT) is used to get the reference signals for series APF,
while instantaneous sequence component theory (ISCT) is used for
the control of Shunt APF. The performance of the implemented
control algorithm is evaluated in terms of power-factor correction,
load balancing, neutral source current mitigation and mitigation of
voltage and current harmonics, voltage sag and swell in a three-phase
four-wire distribution system for different combination of linear and
non-linear loads. In this proposed control scheme of UPQC, the
current/voltage control is applied over the fundamental supply
currents/voltages instead of fast changing APFs currents/voltages,
there by reducing the computational delay and the required sensors.
MATLAB/Simulink based simulations are obtained, which support
the functionality of the UPQC. MATLAB/Simulink based
simulations are obtained, which support the functionality of the
UPQC.
Abstract: As business environments are rapidly changing,
the manufacturing system must be reconfigured to adapt to
various customer needs. In order to cope with this challenge, it
is quintessential to test industrial control logic rapidly and
easily in the design time, and monitor operational behavior in
the run time of automated manufacturing system. Proposed
integrated model for virtual prototyping and operational
monitoring of industrial control logic is to improve limitations
of current ladder programming practices and general discrete
event simulation method. Each plant layout model using HMI
package and object-oriented control logic model is designed
independently and is executed simultaneously in integrated
manner to reflect design practices of automation system in the
design time. Control logic is designed and executed using UML
activity diagram without considering complicated control
behavior to deal with current trend of reconfigurable
manufacturing. After the physical installation, layout model of
virtual prototype constructed in the design time is reused for
operational monitoring of system behavior during run time.
Abstract: This paper presents a new approach for busbar protection with stable operation of current transformer during saturation, using fuzzy neuro and symmetrical components theory. This technique uses symmetrical components of current signals to learn the hidden relationship existing in the input patterns. Simulation studies are preformed and the influence of changing system parameters such as inception fault and source impedance is studied. Details of the design procedure and the results of performance studies with the proposed relay are given in the paper. An analysis of the performance of the proposed technique during ct saturation conditions is presented. The performance of the technique was investigated for a variety of operating conditions and for several busbar configurations. Data generated by EMTDC simulations of model power systems were used in the investigations. The results indicate that the proposed technique is stable during ct saturation conditions.
Abstract: Since the world printing industry has to confront
globalization with a constant change, the Thai printing industry, as a
small but increasingly significant part of the world printing industry,
cannot inevitably escape but has to encounter with the similar change
and also the need to revamp its production processes, designs and
technology to make them more appealing to both international and
domestic market. The essential question is what is the Thai
competitive edge in the printing industry in changing environment?
This research is aimed to study the Thai level of competitive edge in
terms of marketing, technology, environment friendly, and the level
of satisfaction of the process of using printing machines. To access
the extent to which is the trends in competitiveness of Thai printing
industry, both quantitative and qualitative study were conducted. The
quantitative analysis was restricted to 100 respondents. The
qualitative analysis was restricted to a focus group of 10 individuals
from various backgrounds in the Thai printing industry. The findings
from the quantitative analysis revealed that the overall mean scores
are 4.53, 4.10, and 3.50 for the competitiveness of marketing, the
competitiveness of technology, and the competitiveness of being
environment friendly respectively. However, the level of satisfaction
for the process of using machines has a mean score only 3.20. The
findings from the qualitative analysis have revealed that target
customers have increasingly reordered due to their contentment in
both low prices and the acceptable quality of the products. Moreover,
the Thai printing industry has a tendency to convert to ambient green
technology which is friendly to the environment. The Thai printing
industry is choosing to produce or substitute with products that are
less damaging to the environment. It is also found that the Thai
printing industry has been transformed into a very competitive
industry which bargaining power rests on consumers who have a
variety of choices.