Abstract: The present study conducted experimental investigation on combustion and emission characteristics of compression ignition engine using diesel as pilot fuel and methane, hydrogen and methane/hydrogen mixture as gaseous fuels at 1800 rev min-1. The effect of gaseous fuel on peak cylinder pressure and heat release is modest at low to medium loads. At high load, the high combustion temperature and high quantity of pilot fuel contribute to better combustion efficiency for all kinds of gaseous fuels and increases the peak cylinder pressure. Enrichment of hydrogen in methane gradually increases the peak cylinder pressure. The brake thermal efficiency increases with higher hydrogen fraction at lower loads. Hydrogen addition in methane contributed to a proportional reduction of CO/CO2/HC emission without penalty of NOx. For particulate emission, methane and hydrogen, could both suppress the particle emission. 30% hydrogen fraction in methane is observed to be best in reducing the particulate emission.
Abstract: Thailand is the agriculture country as the weather and geography are suitable for agriculture environment. In 2011, the quantity of exported fresh vegetable was 126,069 tons which valued 117.1 million US dollars. Although the fresh vegetable has a high potential in exporting, there also have a lack of knowledge such as chemical usage, land usage, marketing and also the transportation and logistics. Nakorn Pathom province is the area which the farmer and manufacturer of fresh vegetable located. The objectives of this study are to study the basic information of the local fresh vegetable farmers in Nakorn Pathom province, to study the factor which effects the management of the fresh vegetable supply chain in Nakorn Pathom province and to study the problems and obstacle of the fresh vegetable supply chain in Nakorn Pathom province. This study is limited to the flow of the Nakorn Pathom province fresh vegetable from the farmers to the country which import the vegetable from Thailand. The populations of this study are 100 local farmers in Nakorn Pathom province. The result of this study shows that the key process of the fresh vegetable supply chain is in the supply sourcing process and manufacturing process.
Abstract: In this study, we used a two-stage process and
potassium hydroxide (KOH) to transform waste biomass (rice straw)
into activated carbon and then evaluated the adsorption capacity of the
waste for removing carbofuran from an aqueous solution. Activated
carbon was fast and effective for the removal of carbofuran because of
its high surface area. The native and carbofuran-loaded adsorbents
were characterized by elemental analysis. Different adsorption
parameters, such as the initial carbofuran concentration, contact time,
temperature and pH for carbofuran adsorption, were studied using a
batch system. This study demonstrates that rice straw can be very
effective in the adsorption of carbofuran from bodies of water.
Abstract: Biochemical Oxygen Demand (BOD) is a measure of
the oxygen used in bacteria mediated oxidation of organic substances
in water and wastewater. Theoretically an infinite time is required for
complete biochemical oxidation of organic matter, but the
measurement is made over 5-days at 20 0C or 3-days at 27 0C test
period with or without dilution. Researchers have worked to further
reduce the time of measurement.
The objective of this paper is to review advancement made in
BOD measurement primarily to minimize the time and negate the
measurement difficulties. Survey of literature review in four such
techniques namely BOD-BARTTM, Biosensors, Ferricyanidemediated
approach, luminous bacterial immobilized chip method.
Basic principle, method of determination, data validation and their
advantage and disadvantages have been incorporated of each of the
methods.
In the BOD-BARTTM method the time lag is calculated for the
system to change from oxidative to reductive state. BIOSENSORS
are the biological sensing element with a transducer which produces
a signal proportional to the analyte concentration. Microbial species
has its metabolic deficiencies. Co-immobilization of bacteria using
sol-gel biosensor increases the range of substrate. In ferricyanidemediated
approach, ferricyanide has been used as e-acceptor instead
of oxygen. In Luminous bacterial cells-immobilized chip method,
bacterial bioluminescence which is caused by lux genes was
observed. Physiological responses is measured and correlated to
BOD due to reduction or emission.
There is a scope to further probe into the rapid estimation of BOD.
Abstract: An adaptive Helmholtz resonator was designed and
adapted to hydraulics. The resonator was controlled by open- and
closed-loop controls so that 20 dB attenuation of the peak-to-peak
value of the pulsating pressure was maintained. The closed-loop
control was noted to be better, albeit it was slower because of its low
pressure and temperature variation, which caused variation in the
effective bulk modulus of the hydraulic system. Low-pressure
hydraulics contains air, which affects the stiffness of the hydraulics,
and temperature variation changes the viscosity of the oil. Thus, an
open-loop control loses its efficiency if a condition such as
temperature or the amount of air changes after calibration. The
instability of the low-pressure hydraulic system reduced the
operational frequency range of the Helmholtz resonator when
compared with the results of an analytical model.
Different dampers for hydraulics are presented. Then analytical
models of a hydraulic pipe and a hydraulic pipe with a Helmholtz
resonator are presented. The analytical models are based on the wave
equation of sound pressure. Finally, control methods and the results
of experiments are presented.
Abstract: In this paper, a new reverse converter for the moduli set {2n, 2n–1, 2n–1–1} is presented. We improved a previously introduced conversion algorithm for deriving an efficient hardware design for reverse converter. Hardware architecture of the proposed converter is based on carry-save adders and regular binary adders, without the requirement for modular adders. The presented design is faster than the latest introduced reverse converter for moduli set {2n, 2n–1, 2n–1–1}. Also, it has better performance than the reverse converters for the recently introduced moduli set {2n+1–1, 2n, 2n–1}
Abstract: As the demand for higher capacity in a cellular environment increases, the cell size decreases. This fact makes the role of suitable handoff algorithms to reduce both number of handoffs and handoff delay more important. In this paper we show that applying the grey prediction technique for handoff leads to considerable decrease in handoff delay with using a small number of handoffs, compared with traditional hystersis based handoff algorithms.
Abstract: Hepatocellular carcinoma, also called hepatoma, most
commonly appears in a patient with chronic viral hepatitis. In
patients with a higher suspicion of HCC, such as small or subtle
rising of serum enzymes levels, the best method of diagnosis
involves a CT scan of the abdomen, but only at high cost. The aim of
this study was to increase the ability of the physician to early detect
HCC, using a probabilistic neural network-based approach, in order
to save time and hospital resources.
Abstract: Web 2.0 (social networking, blogging and online
forums) can serve as a data source for social science research because
it contains vast amount of information from many different users.
The volume of that information has been growing at a very high rate
and becoming a network of heterogeneous data; this makes things
difficult to find and is therefore not almost useful. We have proposed
a novel theoretical model for gathering and processing data from
Web 2.0, which would reflect semantic content of web pages in
better way. This article deals with the analysis part of the model and
its usage for content analysis of blogs. The introductory part of the
article describes methodology for the gathering and processing data
from blogs. The next part of the article is focused on the evaluation
and content analysis of blogs, which write about specific trend.
Abstract: This current research focused on development of degradable starch based packaging film with enhanced mechanical properties. A series of low density polyethylene (LDPE)/tapioca starch compounds with various tapioca starch contents were prepared by twin screw extrusion with the addition of maleic anhydride grafted polyethylene as compatibilizer. Palm cooking oil was used as processing aid to ease the blown film process, thus, degradable film can be processed via conventional blown film machine. Studies on their characteristics, mechanical properties and biodegradation were carried out by Fourier Transform Infrared (FTIR) spectroscopy and optical properties, tensile test and exposure to fungi environment respectively. The presence of high starch contents had an adverse effect on the tensile properties of LDPE/tapioca starch blends. However, the addition of compatibilizer to the blends improved the interfacial adhesion between the two materials, hence, improved the tensile properties of the films. High content of starch amount also was found to increase the rate of biodegradability of LDPE/tapioca starch films. It can be proved by exposure of the film to fungi environment. A growth of microbes colony can be seen on the surface of LDPE/tapioca starch film indicates that the granular starch present on the surface of the polymer film is attacked by microorganisms, until most of it is assimilated as a carbon source.
Abstract: The classic problem of recovering arbitrary values of
a band-limited signal from its samples has an added complication
in software radio applications; namely, the resampling calculations
inevitably fold aliases of the analog signal back into the original
bandwidth. The phenomenon is quantified by the spur-free dynamic
range. We demonstrate how a novel application of the Remez (Parks-
McClellan) algorithm permits optimal signal recovery and SFDR, far
surpassing state-of-the-art resamplers.
Abstract: Carbon nanotubes (CNTs) are attractive because of
their excellent chemical durability mechanical strength and electrical
properties. Therefore there is interest in CNTs for not only electrical
and mechanical application, but also biological and medical
application.
In this study, the dispersion power of surfactant-treated multiwalled
carbon nanotubes (MWCNTs) and their effect on the antibacterial
activity were examined. Surfactant was used sodium
dodecyl-benzenesulfonate (SDBS). UV-vis absorbance and
transmission electron microscopy(TEM) were used to characterize the
dispersion of MWCNTs in the aqueous phase, showing that the
surfactant molecules had been adsorbed onto the MWCNTs surface.
The surfactant-treated MWCNTs exhibited antimicrobial activities
to streptococcus mutans. The optical density growth curves and viable
cell number determined by the plating method suggested that the
antimicrobial activity of surfactant-treated MWCNTs was both
concentration and treatment time-dependent.
Abstract: An efficient parallel form in digital signal processor can improve the algorithm performance. The butterfly structure is an important role in fast Fourier transform (FFT), because its symmetry form is suitable for hardware implementation. Although it can perform a symmetric structure, the performance will be reduced under the data-dependent flow characteristic. Even though recent research which call as novel memory reference reduction methods (NMRRM) for FFT focus on reduce memory reference in twiddle factor, the data-dependent property still exists. In this paper, we propose a parallel-computing approach for FFT implementation on digital signal processor (DSP) which is based on data-independent property and still hold the property of low-memory reference. The proposed method combines final two steps in NMRRM FFT to perform a novel data-independent structure, besides it is very suitable for multi-operation-unit digital signal processor and dual-core system. We have applied the proposed method of radix-2 FFT algorithm in low memory reference on TI TMSC320C64x DSP. Experimental results show the method can reduce 33.8% clock cycles comparing with the NMRRM FFT implementation and keep the low-memory reference property.
Abstract: Electrical resistivity is a fundamental parameter of metals or electrical conductors. Since resistivity is a function of temperature, in order to completely understand the behavior of metals, a temperature dependent theoretical model is needed. A model based on physics principles has recently been developed to obtain an equation that relates electrical resistivity to temperature. This equation is dependent upon a parameter associated with the electron travel time before being scattered, and a parameter that relates the energy of the atoms and their separation distance. Analysis of the energy parameter reveals that the equation is optimized if the proportionality term in the equation is not constant but varies over the temperature range. Additional analysis reveals that the theoretical equation can be used to determine the mean free path of conduction electrons, the number of defects in the atomic lattice, and the ‘equivalent’ charge associated with the metallic bonding of the atoms. All of this analysis provides validation for the theoretical model and provides insight into the behavior of metals where performance is affected by temperatures (e.g., integrated circuits and temperature sensors).
Abstract: To simulate heating systems in buildings, a research oriented computer code has been developed in Sharif University of Technology in Iran where the climate, existing heating equipment in buildings, consumer behavior and their interactions are considered for simulating energy consumption in conventional systems such as heaters, radiators and fan-coils. In order to validate the computer code, the available data of five buildings was used and the computed consumed energy was compared with the estimated energy extracted from monthly bills. The initial heating system was replaced by the alternative system and the effect of this change was observed on the energy consumption. As a result, the effect of changing heating equipment on energy consumption was investigated in different climates. Changing heater to radiator renders energy conservation up to 50% in all climates and changing radiator to fan-coil decreases energy consumption in climates with cold and dry winter.
Abstract: This paper presents the design and implementation of a fully integrated transimpedance amplifier (TIA) as the analog frontend receiver for Capacitive Micromachined Ultrasound Transducers (CMUTs) for ultrasound biomicroscope imaging application. The amplifier is designed to amplify the received signals from 17.5MHz to 52.5MHz with a center frequency of 35MHz. The TIA was fabricated in GF 0.18μm 1P6M 30V high voltage process. The measurement results show that the designed amplifier can reach a transimpedance gain of 61.08dBΩ and operating frequency from 17.5MHz to 100MHz with 1VP-P output voltage under 6V power supply.
Abstract: Sorghum flour was supplemented with 15 and 30%
chickpea flour. Sorghum flour and the supplement were fermented at
35 oC for 0, 8, 16, and 24 h. Changes in pH, titrable acidity, total
soluble solids, protein content, in vitro protein digestibility and
amino acid composition were investigated during fermentation and/or
after supplementation of sorghum flour with chickpea. The pH of the
fermenting material decreased sharply with a concomitant increase in
the titrable acidity. The total soluble solids remained unchanged with
progressive fermentation time. The protein content of sorghum
cultivar was found to be 9.27 and that of chickpea was 22.47%. The
protein content of sorghum cultivar after supplementation with15 and
30% chickpea was significantly (P ≤ 0.05) increased to 11.78 and
14.55%, respectively. The protein digestibility also increased after
fermentation from 13.35 to 30.59 and 40.56% for the supplements,
respectively. Further increment in protein content and digestibility
was observed when supplemented and unsupplemented samples were
fermented for different periods of time. Cooking of fermented
samples was found to increase the protein content slightly and
decreased digestibility for both supplements. Amino acid content of
fermented and fermented and cooked supplements was determined.
Supplementation was found to increase the lysine and therionine
content. Cooking following fermentation decreased lysine,
isoleucine, valine and sulfur containg amino acids.
Abstract: User interaction components of Augmented Reality (AR) systems have to be tested with users in order to find and fix usability problems as early as possible. In this paper we will report on a user-centered design approach for AR systems following the experience acquired during the design and evaluation of a software prototype for an AR-based educational platform. In this respect we will focus on the re-design of the user task based on the results from a formative usability evaluation. The basic idea of our approach is to describe task scenarios in a tabular format, to develop a task model in a task modeling environment and then to simulate the execution.
Abstract: The experiment was performed to evaluate the effect
of GA3, 2,4-D on fruit growth and fruit quality of wax apple. The
experiment consisted of Red A, Monulla, Atu, Red B cultivars. GA3
and 2,4-D were applied at the small bud and petal fall stage.
Physiological, biochemical characters of fruit were recoded. The
result showed application of GA3, 2,4-D greatly response in
increasing fruit set for all treatment as compared to control. Fruit
weight, fruit size were increased at 10 ppm 2,4-D in ‘Red A’, ‘Red
B’, however it was also enhancing at 10 ppm GA3 in ‘Monulla’,
‘Atu’. For ‘Monulla’, ‘Atu’ fruit crack reduced by 10 ppm 2,4-D
application, but ‘Red B’, ‘Red A’ gave least fruit crack at 10 and 30
ppm GA3, respectively. ‘Monulla’, ‘Atu’ and ‘Red B’ resulted in
response well to 10 ppm GA3 on improving TSS, whereas
application of 30 ppm GA3 greatly enhancing TSS in ‘Red A’. For
‘Atu’ titratable acidity markedly reduced by 10 ppm GA3
application, but spraying with 30 ppm GA3 greatly response in
reducing titratable acidity in ‘Red A’, ‘Red B’ and ‘Monulla’. It was
concluded that GA3, 2,4-D can be an effective tool to enhancing fruit
set, fruit growth as well as improving fruit quality of wax apple.
Abstract: Pressure driven microscale gas flow-separation has
been investigated by solving the compressible Navier-Stokes (NS)
system of equations. A two dimensional explicit finite volume (FV)
compressible flow solver has been developed using modified
advection upwind splitting methods (AUSM+) with no-slip/first
order Maxwell-s velocity slip conditions to predict the flowseparation
behavior in microdimensions. The effects of scale-factor
of the flow geometry and gas species on the microscale gas flowseparation
have been studied in this work. The intensity of flowseparation
gets reduced with the decrease in scale of the flow
geometry. In reduced dimension, flow-separation may not at all be
present under similar flow conditions compared to the larger flow
geometry. The flow-separation patterns greatly depend on the
properties of the medium under similar flow conditions.