Abstract: The objective of this research is to study plant layout
of iron manufacturing based on the systematic layout planning
pattern theory (SLP) for increased productivity. In this case study,
amount of equipments and tools in iron production are studied. The
detailed study of the plant layout such as operation process chart,
flow of material and activity relationship chart has been investigated.
The new plant layout has been designed and compared with the
present plant layout. The SLP method showed that new plant layout
significantly decrease the distance of material flow from billet
cutting process until keeping in ware house.
Abstract: The paper presents a detailed calculation of characteristic of five different topology permanent magnet machines for high performance traction including hybrid -electric vehicles using finite element analysis (FEA) method. These machines include V-shape single layer interior PM, W-shape single-layer interior PM, Segment interior PM and surface PM on the rotor and with distributed winding on the stator. The performance characteristics which include the back-emf voltage and its harmonic, magnet mass, iron loss and ripple torque are compared and analyzed. One of a 7.5kW IPM prototype was tested and verified finite-element analysis results. The aim of the paper is given some guidance and reference for machine designer which are interested in IPM machine selection for high performance traction application.
Abstract: Probabilistic characteristics of seismic responses of the
Partially Restrained connection rotation (PRCR) and panel zone
deformation (PZD) installed in older steel moment frames were
investigated in accordance with statistical inference in
decision-making process. The 4, 6 and 8 story older steel moment
frames with clip angle and T-stub connections were designed and
analyzed using 2%/50yrs ground motions in four cities of the
Mid-America earthquake region. The probability density function and
cumulative distribution function of PRCR and PZD were determined
by the goodness-of-fit tests based on probabilistic parameters
measured from the results of the nonlinear time-history analyses. The
obtained probabilistic parameters and distributions can be used to find
out what performance level mainly PR connections and panel zones
satisfy and how many PR connections and panel zones experience a
serious damage under the Mid-America ground motions.
Abstract: Timing driven physical design, synthesis, and
optimization tools need efficient closed-form delay models for
estimating the delay associated with each net in an integrated circuit
(IC) design. The total number of nets in a modern IC design has
increased dramatically and exceeded millions. Therefore efficient
modeling of interconnection is needed for high speed IC-s. This
paper presents closed–form expressions for RC and RLC
interconnection trees in current mode signaling, which can be
implemented in VLSI design tool. These analytical model
expressions can be used for accurate calculation of delay after the
design clock tree has been laid out and the design is fully routed.
Evaluation of these analytical models is several orders of magnitude
faster than simulation using SPICE.
Abstract: Resistance spot welding process comprises of electric,
thermal and mechanical phenomenon, which makes this process
complex and highly non-linear and thus, it becomes difficult to model
it. In order to obtain good weld nugget during spot welding, hit and
trial welds are usually done which is very costly. Therefore the
numerical simulation research has been conducted to understand the
whole process. In this paper three different cases were analyzed by
varying the tip contact area and it was observed that, with the
variation of tip contact area the nugget formation at the faying
surface is affected. The tip contact area of the welding electrode
becomes large with long welding cycles. Therefore in order to
maintain consistency of nugget formation during the welding process,
the current compensation in control feedback is required. If the
contact area of the welding electrode tip is reduced, a large amount of
current flows through the faying surface, as a result of which
sputtering occurs.
Abstract: The aged are faced with increasing risk for falls. The
aged have the easily fragile bones than others. When falls have
occurred, it is important to detect this emergency state because such
events often lead to more serious illness or even death. A
implementation of PDA system, for detection of emergency situation,
was developed using 3-axis accelerometer in this paper as follows.
The signals were acquired from the 3-axis accelerometer, and then
transmitted to the PDA through Bluetooth module. This system can
classify the human activity, and also detect the emergency state like
falls. When the fall occurs, the system generates the alarm on the
PDA. If a subject does not respond to the alarm, the system determines
whether the current situation is an emergency state or not, and then
sends some information to the emergency center in the case of urgent
situation. Three different studies were conducted on 12 experimental
subjects, with results indicating a good accuracy. The first study was
performed to detect the posture change of human daily activity. The
second study was performed to detect the correct direction of fall. The
third study was conducted to check the classification of the daily
physical activity. Each test was lasted at least 1 min. in third study.
The output of acceleration signal was compared and evaluated by
changing a various posture after attaching a 3-axis accelerometer
module on the chest. The newly developed system has some important
features such as portability, convenience and low cost. One of the
main advantages of this system is that it is available at home
healthcare environment. Another important feature lies in low cost to
manufacture device. The implemented system can detect the fall
accurately, so will be widely used in emergency situation.
Abstract: Base on extenics theory, the statistical physical and mechanical properties from laboratory experiments are used to evaluate the bearing capacity of lateritic soil foundation. The properties include water content, bulk density, liquid limit, cohesion, and so on. The matter-element and the dependent function are defined. Then the synthesis dependent degree and the final grade index are calculated. The results show that predicted outcomes can be matched with the in-situ test data, and a evaluate grade associate with bearing capacity can be deduced. The results provide guidance to assess and determine the bearing capacity grade of lateritic soil foundation.
Abstract: We report a lithography-free approach to fabricate the
biomimetics, quasi-beehive Si nanostructures (QBSNs), on
Si-substrates. The self-assembled SiGe nanoislands via the strain
induced surface roughening (Asaro-Tiller-Grinfeld instability) during
in-situ annealing play a key role as patterned sacrifice regions for
subsequent reactive ion etching (RIE) process performed for
fabricating quasi-beehive nanostructures on Si-substrates. As the
measurements of field emission, the bare QBSNs show poor field
emission performance, resulted from the existence of the native oxide
layer which forms an insurmountable barrier for electron emission. In
order to dramatically improve the field emission characteristics, the
platinum nanopillars (Pt-NPs) were deposited on QBSNs to form
Pt-NPs/QBSNs heterostructures. The turn-on field of Pt-NPs/QBSNs
is as low as 2.29 V/μm (corresponding current density of 1 μA/cm2),
and the field enhancement factor (β-value) is significantly increased to
6067. More importantly, the uniform and continuous electrons excite
light emission, due to the surrounding filed emitters from
Pt-NPs/QBSNs, can be easily obtained. This approach does not require
an expensive photolithographic process and possesses great potential
for applications.
Abstract: The purpose of this study is to derive parameters
estimating for the Lyman–Kutcher–Burman (LKB) normal tissue
complication probability (NTCP) model using analysis of scintigraphy
assessments and quality of life (QoL) measurement questionnaires for
the parotid gland (xerostomia). In total, 31 patients with
head-and-neck (HN) cancer were enrolled. Salivary excretion factor
(SEF) and EORTC QLQ-H&N35 questionnaires datasets are used for
the NTCP modeling to describe the incidence of grade 4 xerostomia.
Assuming that n= 1, NTCP fitted parameters are given as TD50= 43.6
Gy, m= 0.18 in SEF analysis, and as TD50= 44.1 Gy, m= 0.11 in QoL
measurements, respectively. SEF and QoL datasets can validate the
Quantitative Analyses of Normal Tissue Effects in the Clinic
(QUANTEC) guidelines well, resulting in NPV-s of 100% for the both
datasets and suggests that the QUANTEC 25/20Gy gland-spared
guidelines are suitable for clinical used for the HN cohort to
effectively avoid xerostomia.
Abstract: Data of wave height and wind speed were collected
from three existing oil fields in South China Sea – offshore
Peninsular Malaysia, Sarawak and Sabah regions. Extreme values
and other significant data were employed for analysis. The data were
recorded from 1999 until 2008. The results show that offshore
structures are susceptible to unacceptable motions initiated by wind
and waves with worst structural impacts caused by extreme wave
heights. To protect offshore structures from damage, there is a need
to quantify descriptive statistics and determine spectra envelope of
wind speed and wave height, and to ascertain the frequency content
of each spectrum for offshore structures in the South China Sea
shallow waters using measured time series. The results indicate that
the process is nonstationary; it is converted to stationary process by
first differencing the time series. For descriptive statistical analysis,
both wind speed and wave height have significant influence on the
offshore structure during the northeast monsoon with high mean wind
speed of 13.5195 knots ( = 6.3566 knots) and the high mean wave
height of 2.3597 m ( = 0.8690 m). Through observation of the
spectra, there is no clear dominant peak and the peaks fluctuate
randomly. Each wind speed spectrum and wave height spectrum has
its individual identifiable pattern. The wind speed spectrum tends to
grow gradually at the lower frequency range and increasing till it
doubles at the higher frequency range with the mean peak frequency
range of 0.4104 Hz to 0.4721 Hz, while the wave height tends to
grow drastically at the low frequency range, which then fluctuates
and decreases slightly at the high frequency range with the mean
peak frequency range of 0.2911 Hz to 0.3425 Hz.
Abstract: The recent development in learning technologies leads
to emerge many learning management systems (LMS). In this study,
we concentrate on the specifications and characteristics of LMSs.
Furthermore, this paper emphasizes on the feature of e-learning
management systems. The features take on the account main
indicators to assist and evaluate the quality of e-learning systems.
The proposed indicators based of ten dimensions.
Abstract: Natural gas flow contains undesirable solid particles,
liquid condensation, and/or oil droplets and requires reliable
removing equipment to perform filtration. Recent natural gas
processing applications are demanded compactness and reliability of
process equipment. Since conventional means are sophisticated in
design, poor in efficiency, and continue lacking robust, a supersonic
nozzle has been introduced as an alternative means to meet such
demands.
A 3-D Convergent-Divergent Nozzle is simulated using
commercial Code for pressure ratio (NPR) varies from 1.2 to 2. Six
different shapes of nozzle are numerically examined to illustrate the
position of shock-wave as such spot could be considered as a
benchmark of particle separation. Rectangle, triangle, circular,
elliptical, pentagon, and hexagon nozzles are simulated using Fluent
Code with all have same cross-sectional area.
The simple one-dimensional inviscid theory does not describe the
actual features of fluid flow precisely as it ignores the impact of
nozzle configuration on the flow properties. CFD Simulation results,
however, show that nozzle geometry influences the flow structures
including location of shock wave.
The CFD analysis predicts shock appearance when p01/pa>1.2 for
almost all geometry and locates at the lower area ratio (Ae/At).
Simulation results showed that shock wave in Elliptical nozzle has
the farthest distance from the throat among the others at relatively
small NPR. As NPR increases, hexagon would be the farthest. The
numerical result is compared with available experimental data and
has shown good agreement in terms of shock location and flow
structure.
Abstract: A genetic algorithm (GA) based feature subset
selection algorithm is proposed in which the correlation structure of
the features is exploited. The subset of features is validated according
to the classification performance. Features derived from the
continuous wavelet transform are potentially strongly correlated.
GA-s that do not take the correlation structure of features into
account are inefficient. The proposed algorithm forms clusters of
correlated features and searches for a good candidate set of clusters.
Secondly a search within the clusters is performed. Different
simulations of the algorithm on a real-case data set with strong
correlations between features show the increased classification
performance. Comparison is performed with a standard GA without
use of the correlation structure.
Abstract: Intermittent aeration process can be easily applied on
the existing activated sludge system and is highly reliable against the loading changes. It can be operated in a relatively simple way as well.
Since the moving-bed biofilm reactor method processes pollutants by attaching and securing the microorganisms on the media, the process
efficiency can be higher compared to the suspended growth biological
treatment process, and can reduce the return of sludge. In this study,
the existing intermittent aeration process with alternating flow being
applied on the oxidation ditch is applied on the continuous flow stirred tank reactor with advantages from both processes, and we would like
to develop the process to significantly reduce the return of sludge in the clarifier and to secure the reliable quality of treated water by
adding the moving media. Corresponding process has the appropriate
form as an infrastructure based on u- environment in future u- City and
is expected to accelerate the implementation of u-Eco city in conjunction with city based services. The system being conducted in a
laboratory scale has been operated in HRT 8hours except for the final
clarifier and showed the removal efficiency of 97.7 %, 73.1 % and 9.4
% in organic matters, TN and TP, respectively with operating range of
4hour cycle on system SRT 10days. After adding the media, the removal efficiency of phosphorus showed a similar level compared to
that before the addition, but the removal efficiency of nitrogen was
improved by 7~10 %. In addition, the solids which were maintained in
MLSS 1200~1400 at 25 % of media packing were attached all onto the
media, which produced no sludge entering the clarifier. Therefore, the
return of sludge is not needed any longer.
Abstract: This study investigates the roles of knowledge
acquisition, absorptive capacity, and innovation capability in finance
and manufacturing industries. With 362 valid questionnaires from
manufactures and financial industries in Taiwan, we examine the
relationships between absorptive capacity, knowledge acquisition and
innovation capability using a structural equation model. The results
indicate that absorptive capacity is the mediator between knowledge
acquisition and innovation capability, and that knowledge acquisition
has a positive effect on absorptive capacity.
Abstract: In order to implement flexibility as well as survivable
capacities over passive optical network (PON), a new automatic
random fault-recovery mechanism with array-waveguide-grating
based (AWG-based) optical switch (OSW) is presented. Firstly,
wavelength-division-multiplexing and optical code-division
multiple-access (WDM/OCDMA) scheme are configured to meet the
various geographical locations requirement between optical network
unit (ONU) and optical line terminal (OLT). The AWG-base optical
switch is designed and viewed as central star-mesh topology to
prohibit/decrease the duplicated redundant elements such as fiber and
transceiver as well. Hence, by simple monitoring and routing switch
algorithm, random fault-recovery capacity is achieved over
bi-directional (up/downstream) WDM/OCDMA scheme. When error
of distribution fiber (DF) takes place or bit-error-rate (BER) is higher
than 10-9 requirement, the primary/slave AWG-based OSW are
adjusted and controlled dynamically to restore the affected ONU
groups via the other working DFs immediately.
Abstract: In this paper, linear multistep technique using power
series as the basis function is used to develop the block methods
which are suitable for generating direct solution of the special second
order ordinary differential equations of the form y′′ = f(x,y), a < = x < = b with associated initial or boundary conditions. The continuaous hybrid formulations enable us to differentiate and evaluate at some
grids and off – grid points to obtain two different three discrete
schemes, each of order (4,4,4)T, which were used in block form for
parallel or sequential solutions of the problems. The computational
burden and computer time wastage involved in the usual reduction of
second order problem into system of first order equations are avoided
by this approach. Furthermore, a stability analysis and efficiency of
the block method are tested on linear and non-linear ordinary
differential equations whose solutions are oscillatory or nearly
periodic in nature, and the results obtained compared favourably with
the exact solution.
Abstract: Participation in global trade means that Chinas vegetables and fruits industry faces international food safety standards and increased scrutiny worldwide. The objectives of this paper were to investigate how existing food safety standards and regulations in the importing countries impact the export of vegetables and fruits from China. This paper discussed the current and historical situations of Chinas vegetables and fruits export from 1996 to 2010, analyzed the Maximum Residual Limit (MRL) standards of pesticides imposed by importing countries, quantitatively estimated the impacts of food safety standards on Chinas vegetables and fruits export based on a gravity model. The results showed that although transportation distance between trade partners and tariff rates on vegetables and fruits were still the importantly resistant factors for China export, vegetables and fruits export was sensitive to the number of regulated pesticides, the strictness, and the level of food safety standards imposed by importing countries, which showed a significant trade flow effect, stricter food safety standards, increased number of regulated pesticides significantly inhibit China export of vegetables and fruits. Moreover, Chinas food safety standards also showed a significantly effect on vegetables and fruits export, which inhibited export to some extent. KeywordsFood safety standards, MRL, Vegetables, Fruits, Export.
Abstract: Using steelmaking slag as a raw material, aragonite superstructure product had been synthesized via an indirect CO2 mineral sequestration rout. It mainly involved two separate steps, in which the element of calcium is first selectively leached from steelmaking slag by a novel leaching media consisting of organic solvent Tributyl phosphate (TBP), acetic acid, and ultra-purity water, followed by enhanced carbonation in a separate step for aragonite superstructure production as well as efficiency recovery of leaching media. Based on the different leaching medium employed in the steelmaking slag leaching process, two typical products were collected from the enhanced carbonation step. The products were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM), respectively. It reveals that the needle-like aragonite crystals self-organized into aragonite superstructure particles including aragonite microspheres as well as dumbbell-like spherical particles, can be obtained from the steelmaking slag with the purity over 99%.
Abstract: This paper presents a novel approach to finding a
priori interesting regions in mammograms. In order to delineate those
regions of interest (ROI-s) in mammograms, which appear to be
prominent, a topographic representation called the iso-level contour
map consisting of iso-level contours at multiple intensity levels and
region segmentation based-thresholding have been proposed. The
simulation results indicate that the computed boundary gives the
detection rate of 99.5% accuracy.