Abstract: A numerical solution of the initial boundary value
problem of the suspended string vibrating equation with the
particular nonlinear damping term based on the finite difference
scheme is presented in this paper. The investigation of how the
second and third power terms of the nonlinear term affect the
vibration characteristic. We compare the vibration amplitude as a
result of the third power nonlinear damping with the second power
obtained from previous report provided that the same initial shape
and initial velocities are assumed. The comparison results show that
the vibration amplitude is inversely proportional to the coefficient of
the damping term for the third power nonlinear damping case, while
the vibration amplitude is proportional to the coefficient of the
damping term in the second power nonlinear damping case.
Abstract: We proposed the use of a Toda-Rayleigh ring as a
central pattern generator (CPG) for controlling hexapodal robots. We
show that the ring composed of six Toda-Rayleigh units coupled to
the limb actuators reproduces the most common hexapodal gaits. We
provide an electrical circuit implementation of the CPG and test our
theoretical results obtaining fixed gaits. Then we propose a method
of incorporation of the actuator (motor) dynamics in the CPG. With
this approach we close the loop CPG – environment – CPG, thus
obtaining a decentralized model for the leg control that does not
require higher level intervention to the CPG during locomotion in
a nonhomogeneous environments. The gaits generated by the novel
CPG are not fixed, but adapt to the current robot bahvior.
Abstract: An HPLC-UV analytical method was developed to
determine ethylenediaminetetraacetic acid (EDTA) in dairy
wastewater and surface water. The optimizing separation was achieved
by reversed–phase ion-pair liquid chromatography on a C18 column
using methanol as mobile phase solvent, tetrabutylammonium bromide
as the ion-pair reagent in pH 3.3 formate buffer solution at a flow rate
of 0.9 mL min-1 with a UV detector at 265 nm. No interference of Ca,
Mg or NO3
- was detected. Method performance was evaluated in terms
of linearity, repeatability and reproducibility. The method detection
limit was 5 μg L-1. The contents of EDTA in dairy effluents were 72 ~
261 μg L-1 at a large dairy site. A change of EDTA concentration was
observed downstream of the dairy effluent discharge, but this was well
under the predicted no effect concentration for aquatic ecosystem.
Abstract: Network on a chip (NoC) has been proposed as a viable solution to counter the inefficiency of buses in the current VLSI on-chip interconnects. However, as the silicon chip accommodates more transistors, the probability of transient faults is increasing, making fault tolerance a key concern in scaling chips. In packet based communication on a chip, transient failures can corrupt the data packet and hence, undermine the accuracy of data communication. In this paper, we present a comparative analysis of transient fault tolerant techniques including end-to-end, node-by-node, and stochastic communication based on flooding principle.
Abstract: Ipomoea batatas (Sweetpotato) is currently ranked
sixth in the total world food production and are planted mainly for
their storage roots. The present study was undertaken to evaluate and
compare the antioxidant properties of the leaf and carotenoids extract
from the Ipomoea batatas var. Oren leaves. Total flavonoids in the
leaf extract was 144.6 ± 40.5 μg/g compared to 114.86 ± 4.35 μg/g
catechin equivalent in the carotenoids extract. Total polyphenols in
the leaf extracts (3.470 ± 0.024 GAE g/100g DW) was slightly higher
compared to carotenoids extract (2.994 ± 0.078 GAE g/100g DW).
The carotenoids extract marked a higher radical scavenging capacity
with the IC50= 491.86 μg/ml compared to leaf extract (IC50= 545.39
μg/ml). Concentration-dependent reducing activity was observed for
both extracts. Thus, the carotenoids extraction process retained most
of the antioxidant capacity from the leaves and can be made into
potential natural yellow dye with antioxidant property.
Abstract: Through the analysis of the process digital design
based on digital mockup, the fact indicates that a distributed
cooperative supporting environment is the foundation conditions to
adopt design approach based on DMU. Data access authorization is
concerned firstly because the value and sensitivity of the data for the
enterprise. The access control for administrators is often rather weak
other than business user. So authors established an enhanced system to
avoid the administrators accessing the engineering data by potential
approach and without authorization. Thus the data security is
improved.
Abstract: This paper proposes a fast tree join scheme to provide
seamless multicast handover in the mobile networks based on the Fast
Mobile IPv6 (FMIPv6). In the existing FMIPv6-based multicast
handover scheme, the bi-directional tunnelling or the remote
subscription is employed with the packet forwarding from the previous
access router (AR) to the new AR. In general, the remote subscription
approach is preferred to the bi-directional tunnelling one, since in the
remote subscription scheme we can exploit an optimized multicast
path from a multicast source to many mobile receivers. However, in
the remote subscription scheme, if the tree joining operation takes a
long time, the amount of data packets to be forwarded and buffered for
multicast handover will increase, and thus the corresponding buffer
may overflow, which results in severe packet losses. In order to reduce
these costs associated with packet forwarding and buffering, this paper
proposes the fast join to multicast tree, in which the new AR will join
the multicast tree as fast as possible, so that the new multicast data
packets can also arrive at the new AR, by which the packet forwarding
and buffering costs can be reduced. From numerical analysis, it is
shown that the proposed scheme can give better performance than the
existing FMIPv6-based multicast handover schemes in terms of the
multicast packet delivery costs.
Abstract: The purpose of this paper is applied Taguchi method on the optimization for PEMFC performance, and a representative Computational Fluid Dynamics (CFD) model is selectively performed for statistical analysis. The studied factors in this paper are pressure of fuel cell, operating temperature, the relative humidity of anode and cathode, porosity of gas diffusion electrode (GDE) and conductivity of GDE. The optimal combination for maximum power density is gained by using a three-level statistical method. The results confirmed that the robustness of the optimum design parameters influencing the performance of fuel cell are founded by pressure of fuel cell, 3atm; operating temperature, 353K; the relative humidity of anode, 50%; conductivity of GDE, 1000 S/m, but the relative humidity of cathode and porosity of GDE are pooled as error due to a small sum of squares. The present simulation results give designers the ideas ratify the effectiveness of the proposed robust design methodology for the performance of fuel cell.
Abstract: When a small H/W IP is designed, we can develop an
appropriate verification environment by observing the simulated
signal waves, or using the serial test vectors for the fixed output. In the
case of design and verification of a massive parallel processor with
multiple IPs, it-s difficult to make a verification system with existing
common verification environment, and to verify each partial IP. A
TestDrive verification environment can build easy and reliable
verification system that can produce highly intuitive results by
applying Modelsim and SystemVerilog-s DPI. It shows many
advantages, for example a high-level design of a GPGPU processor
design can be migrate to FPGA board immediately.
Abstract: Ethnicity identification of face images is of interest in
many areas of application, but existing methods are few and limited.
This paper presents a fusion scheme that uses block-based uniform
local binary patterns and Haar wavelet transform to combine local
and global features. In particular, the LL subband coefficients of the
whole face are fused with the histograms of uniform local binary
patterns from block partitions of the face. We applied the principal
component analysis on the fused features and managed to reduce the
dimensionality of the feature space from 536 down to around 15
without sacrificing too much accuracy. We have conducted a number
of preliminary experiments using a collection of 746 subject face
images. The test results show good accuracy and demonstrate the
potential of fusing global and local features. The fusion approach is
robust, making it easy to further improve the identification at both
feature and score levels.
Abstract: A SnO2/CdS/CdTe heterojunction was fabricated by
thermal evaporation technique. The fabricated cells were annealed at
573K for periods of 60, 120 and 180 minutes. The structural
properties of the solar cells have been studied by using X-ray
diffraction. Capacitance- voltage measurements were studied for the
as-prepared and annealed cells at a frequency of 102 Hz. The
capacitance- voltage measurements indicated that these cells are
abrupt. The capacitance decreases with increasing annealing time.
The zero bias depletion region width and the carrier concentration
increased with increasing annealing time. The carrier transport
mechanism for the CdS/CdTe heterojunction in dark is tunneling
recombination. The ideality factor is 1.56 and the reverse bias
saturation current is 9.6×10-10A. The energy band lineup for the n-
CdS/p-CdTe heterojunction was investigated using current - voltage
and capacitance - voltage characteristics.
Abstract: In this paper, the significant wave height at the Upper Gulf of Thailand and the changing of wave height at Bangkhuntien shoreline were simulated by using the Simulating WAves Nearshore Model (SWAN) version 40.51. The simulated results indicated that the significant wave height by SWAN model corresponded with the observed data. The results showed that the maximum significant wave height at the Bangkhuntien shoreline were 1.06-2.05 m. and the average significant wave height at the Bangkhuntien shoreline were 0.30-0.47 m. The significant wave height can be used to calculate the erosion through the Bangkhuntien shoreline. The erosion rates at the Bangkhuntien shoreline were prepared by using the aerial photo and they were about 1.80 m/yr. from 1980- 1986, 4.75 m/yr from 1987-1993, 15.28 m/yr from 1994-1996 and 10.03 m/yr from 1997-2002. The relation between the wave energy and the erosion were in good agreement. Therefore, the significant wave height was one of the major factors of the erosion at the Bangkhuntien shoreline.
Abstract: A logic model for analyzing complex systems- stability
is very useful to many areas of sciences. In the real world, we are
enlightened from some natural phenomena such as “biosphere", “food
chain", “ecological balance" etc. By research and practice, and taking
advantage of the orthogonality and symmetry defined by the theory of
multilateral matrices, we put forward a logic analysis model of
stability of complex systems with three relations, and prove it by
means of mathematics. This logic model is usually successful in
analyzing stability of a complex system. The structure of the logic
model is not only clear and simple, but also can be easily used to
research and solve many stability problems of complex systems. As an
application, some examples are given.
Abstract: This study analyzes characteristics determining
member’s willingness to invest in cooperatives using ordered logit
model. The data were collected in a field survey among 122
cooperative members in north-central China. The descriptive analysis
of survey evidence suggests that cooperatives in China generally
having poor ability to deliver the processing services related to
product package, grading, and storage, performing worse in
profitability, inability of providing returns to capital and obtaining
agricultural loan. The regression results demonstrate that members’
farm size, their satisfaction with cooperative price preferential
services, attitudes toward cooperative operational scale and
development potential have statistically significant impact on
willingness to invest.
Abstract: Pressure vessels are usually operating at temperatures
where the conditions of linear elastic fracture mechanics are no
longer met because massive plasticity precedes crack propagation. In
this work the development of a surface crack in a pressure vessel
subject to bending and tension under elastic-plastic fracture
mechanics conditions was investigated. Finite element analysis was
used to evaluate the hydrostatic stress, the J-integral and crack
growth for semi-elliptical surface-breaking cracks. The results
showed non-uniform stress triaxiality and crack driving force around
the crack front at large deformation levels. Different ductile crack
extensions were observed which emphasis the dependent of ductile
tearing on crack geometry and type of loading. In bending the crack
grew only beneath the surface, and growth was suppressed at the
deepest segment. This contrasts to tension where the crack breaks
through the thickness with uniform growth along the entire crack
front except at the free surface. Current investigations showed that
the crack growth developed under linear elastic fracture mechanics
conditions will no longer be applicable under ductile tearing
scenarios.
Abstract: In today-s competitive global business environment,
the concept of supply chain management (SCM) continues to become
increasingly market-oriented, shifting the primary driver of the value
chain from supply to demand. Recent recommendations encourage
researchers to focus investigations on the supply chain process
integration (SCPI) capabilities that integrate a focal firm with its
network of suppliers and business customers to create value for it.
However, theoretical and empirical researches pertaining to the
antecedents and consequences of a focal firm-s SCPI capabilities have
been limited and piecemeal. The purpose of this study is to investigate
the critical determinants and consequences of a focal firm-s SCPI
capabilities. We test our proposed research framework using a sample
of 139 sales managers of manufacturing industries in Taiwan, our
research findings show that (1) both perceived business customer-s
power and focal firm-s market-oriented culture positively influences a
focal firm-s SCPI capabilities, and (2) SCPI capabilities positively
influence a focal firm-s SCM performance, both operational and
strategic benefits. Implications for practitioners and researchers and
suggestions for future research are also addressed in this study.
Abstract: The study aimed to verify a hypothesis that a sense of
fulfillment in student life and perceived stress in training in the
facilities could affect vocational identity among social welfare
university students, in order to acquire implications for enhancing the
vocational consciousness. A questionnaire survey was conducted with
388 third- and fourth-year students of training course for certified
social workers in three universities in A prefecture in Japan. The
questionnaire was returned by 338 students, and 288 responses
(85.2%) were valid and used for the analysis. As a SEM result, the
hypothesized model proved to be fit to the data. Path coefficient of
sense of fulfillment of student life to vocational identity was
statistically positive. Path coefficient of training stress to vocational
identity was statistically negative.
Abstract: Dehydration of methanol to dimethyl ether (DME)
over a commercial Al2O3 catalyst was studied in an isothermal integral
fixed bed reactor. The experiments were performed on the temperature
interval 513-613 K, liquid hourly space velocity (LHSV) of 0.9-2.1h-1,
pressures between 0.1 and 1.0 MPa. The effect of different operation
conditions on the dehydration of methanol was investigated in a
laboratory scale experiment. A new intrinsic kinetics equation based
on the mechanism of Langmuir-Hinshelwood dissociation adsorption
was developed for the dehydration reaction by fitting the expressions
to the experimental data. An activation energy of 67.21 kJ/mol was
obtained for the catalyst with the best performance. Statistic test
showed that this new intrinsic kinetics equation was acceptable.
Abstract: A numerical study on the turbulent flow and heat
transfer characteristics in the rectangular channel with different types
of baffles is carried out. The inclined baffles have the width of 19.8
cm, the square diamond type hole having one side length of 2.55 cm,
and the inclination angle of 5o. Reynolds number is varied between
23,000 and 57,000. The SST turbulence model is applied in the
calculation. The validity of the numerical results is examined by the
experimental data. The numerical results of the flow field depict that
the flow patterns around the different baffle type are entirely different
and these significantly affect the local heat transfer characteristics.
The heat transfer and friction factor characteristics are significantly
affected by the perforation density of the baffle plate. It is found that
the heat transfer enhancement of baffle type II (3 hole baffle) has the
best values.
Abstract: We have fabricated a-IGZO TFT and investigated the
stability under positive DC and AC bias stress. The threshold voltage
of a-IGZO TFT shifts positively under those biases, and that reduces
on-current. For this reason, conventional shift-register circuit
employing TFTs which stressed by positive bias will be unstable, may
do not work properly. We have designed a new 6-transistor
shift-register, which has less transistors than prior circuits. The TFTs
of the proposed shift-register are not suffering from positive DC or AC
stress, mainly kept unbiased. Despite the compact design, the stable
output signal was verified through the SPICE simulation even under
RC delay of clock signal.