Abstract: A solar refrigeration system based on the adsorptiondesorption
phenomena is designed and analyzed. An annular tubular
generator filled with silica gel adsorbent and with a perforated inner
cylinder is integrated within a flat solar collector. The working fluid
in the refrigeration cycle is water. The thermodynamic analysis and
because of the temperature level that could be attained with a flat
solar collector it is required that the system operates under vacuum
conditions. In order to enhance the performance of the system and to
get uniform temperature in the silica gel and higher desorbed mass,
an apparatus for rotation of the generator is incorporated in the
system. Testing is carried out and measurements are taken on the
designed installation. The effect of rotation is checked on the
temperature distribution and on the performance of this machine and
compared to the flat solar collector with fixed generator.
Abstract: Star graphs are Cayley graphs of symmetric groups of permutations, with transpositions as the generating sets. A star graph is a preferred interconnection network topology to a hypercube for its ability to connect a greater number of nodes with lower degree. However, an attractive property of the hypercube is that it has a Hamiltonian decomposition, i.e. its edges can be partitioned into disjoint Hamiltonian cycles, and therefore a simple routing can be found in the case of an edge failure. The existence of Hamiltonian cycles in Cayley graphs has been known for some time. So far, there are no published results on the much stronger condition of the existence of Hamiltonian decompositions. In this paper, we give a construction of a Hamiltonian decomposition of the star graph 5-star of degree 4, by defining an automorphism for 5-star and a Hamiltonian cycle which is edge-disjoint with its image under the automorphism.
Abstract: Faults in a network may take various forms such as hardware/software errors, vertex/edge faults, etc. Folded hypercube is a well-known variation of the hypercube structure and can be constructed from a hypercube by adding a link to every pair of nodes with complementary addresses. Let FFv (respectively, FFe) be the set of faulty nodes (respectively, faulty links) in an n-dimensional folded hypercube FQn. Hsieh et al. have shown that FQn - FFv - FFe for n ≥ 3 contains a fault-free cycle of length at least 2n -2|FFv|, under the constraints that (1) |FFv| + |FFe| ≤ 2n - 4 and (2) every node in FQn is incident to at least two fault-free links. In this paper, we further consider the constraints |FFv| + |FFe| ≤ 2n - 3. We prove that FQn - FFv - FFe for n ≥ 5 still has a fault-free cycle of length at least 2n - 2|FFv|, under the constraints : (1) |FFv| + |FFe| ≤ 2n - 3, (2) |FFe| ≥ n + 2, and (3) every vertex is still incident with at least two links.
Abstract: The performance of a sucrose-based H2 production in
a completely stirred tank reactor (CSTR) was modeled by neural
network back-propagation (BP) algorithm. The H2 production was
monitored over a period of 450 days at 35±1 ºC. The proposed model
predicts H2 production rates based on hydraulic retention time
(HRT), recycle ratio, sucrose concentration and degradation, biomass
concentrations, pH, alkalinity, oxidation-reduction potential (ORP),
acids and alcohols concentrations. Artificial neural networks (ANNs)
have an ability to capture non-linear information very efficiently. In
this study, a predictive controller was proposed for management and
operation of large scale H2-fermenting systems. The relevant control
strategies can be activated by this method. BP based ANNs modeling
results was very successful and an excellent match was obtained
between the measured and the predicted rates. The efficient H2
production and system control can be provided by predictive control
method combined with the robust BP based ANN modeling tool.
Abstract: This research studied recycled wastes by Recyclable Material Bank project of 17 universities of Thailand for evaluation of reducing greenhouse gasses emission compared with landfilling activity during January 2011 to December 2011. The results showed that the projects collected total amount of recyclable wastes about 1,626.917 metric ton. The office paper has the largest amount among these recycled wastes (55.61 % of total recycled wastes). Groups of recycled waste can be prioritized from high to low according to their amount as paper, plastic, glass, mixed recyclables and metal, respectively. The project reduced greenhouse gasses emission equivalent to about 5,263.481 metric ton of carbon dioxide. The most significant recycled waste that affects the reduction of greenhouse gasses emission is office paper which is 73.45% of total reduced greenhouse gasses emission. According to amount of reduced greenhouse gasses emission, groups of recycled waste can be prioritized from high to low significances as paper, plastic, metal, mixed recyclables and glass, respectively.
Abstract: The paper deals with the kinematics and automated
calculation of intermittent mechanisms with radial cams. Currently,
electronic cams are increasingly applied in the drives of working link
mechanisms. Despite a huge advantage of electronic cams in their reprogrammability
or instantaneous change of displacement diagrams,
conventional cam mechanisms have an irreplaceable role in
production and handling machines. With high frequency of working
cycle periods, the dynamic load of the proper servomotor rotor
increases and efficiency of electronic cams strongly decreases.
Though conventional intermittent mechanisms with radial cams are
representatives of fixed automation, they have distinct advantages in
their high speed (high dynamics), positional accuracy and relatively
easy manufacture. We try to remove the disadvantage of firm
displacement diagram by reducing costs for simple design and
automated calculation that leads reliably to high-quality and
inexpensive manufacture.
Abstract: A Negotiation Support is required on a value-based decision to enable each stakeholder to evaluate and rank the solution alternatives before engaging into negotiation with the other stakeholders. This study demonstrates a process of negotiation support model for selection of a building system from value-based design perspective. The perspective is based on comparison of function and cost of a building system. Multi criteria decision techniques were applied to determine the relative value of the alternative solutions for performing the function. A satisfying option game theory are applied to the criteria of value-based decision which are LCC (life cycle cost) and function based FAST. The results demonstrate a negotiation process to select priorities of a building system. The support model can be extended to an automated negotiation by combining value based decision method, group decision and negotiation support.
Abstract: An acyclic coloring of a graph G is a coloring of its
vertices such that:(i) no two neighbors in G are assigned the same
color and (ii) no bicolored cycle can exist in G. The acyclic chromatic
number of G is the least number of colors necessary to acyclically
color G. Recently it has been proved that any graph of maximum
degree 5 has an acyclic chromatic number at most 8. In this paper
we present another proof for this result.
Abstract: The mechanical properties of blends consisting of
plasticized poly(vinyl butyral) (PVB) and plasticized poly(vinyl
chloride) (PVC) are studied, in order to evaluate the possibility of
using recycled PVB waste derived from windshields. PVC was
plasticized with 38% of diisononyl phthalate (DINP), while PVB was
plasticized with 28% of triethylene glycol, bis(2-ethylhexanoate)
(3GO). The optimal process conditions for the PVB/PVC blend in 1:1
ratio were determined. Entropy was used in order to theoretically
predict the blends miscibility. The PVB content of each blend
composition used was ranging from zero to 100%. Tensile strength
and strain were tested. In addition, a comparison between recycled
and original PVB, used as constituents of the blend, was performed.
Abstract: This presentation reviews recent advances in superalloys and thermal barrier coating (TBC) for application in hot sections of energy-efficient gas-turbine engines. It has been reviewed that in the modern combined-cycle gas turbines (CCGT) applying single-crystal energy materials (SC superalloys) and thermal barrier coatings (TBC), and – in one design – closed-loop steam cooling, thermal efficiency can reach more than 60%. These technological advancements contribute to profitable and clean power generation with reduced emission. Alternatively, the use of advanced superalloys (e.g. GTD-111 superalloy, Allvac 718Plus superalloy) and advanced thermal barrier coatings (TBC) in modern gas-turbines has been shown to yield higher energy-efficiency in power generation.
Abstract: A new chelating resin is prepared by coupling
Amberlite XAD-4 with 1-amino-2-naphthole through an azo spacer.
The resulting sorbent has been characterized by FT-IR, elemental
analysis and thermogravimetric analysis (TGA) and studied for
preconcentrating of Cu (II) using flame atomic absorption
spectrometry (FAAS) for metal monitoring. The optimum pH value
for sorption of the copper ions was 6.5. The resin was subjected to
evaluation through batch binding of mentioned metal ion.
Quantitative desorption occurs instantaneously with 0.5 M HNO3.
The sorption capacity was found 4.8 mmol.g-1 of resin for Cu (II) in
the aqueous solution. The chelating resin can be reused for 10 cycles
of sorption-desorption without any significant change in sorption
capacity. A recovery of 99% was obtained the metal ions with 0.5 M
HNO3 as eluting agent. The method was applied for metal ions
determination from industrial waste water sample.
Abstract: The purpose of this paper is to investigate the
durability of cement mortar in presence of Rice Husk Ash (RHA).
The strength and durability of mortar with different replacement
level (0%, 10%, 15%, 20%, 25% and 30%) of Ordinary Portland
Cement (OPC) by RHA is investigated here. RHA was
manufactured from an uncontrolled burning process. Test samples
were prepared with river sand of FM 2.73. Samples were kept in
controlled environment up to test time. The results show that
addition of RHA was shown better results for 20% replacement
level than OPC at 90 days. In durability test all samples passed for
20 cycles except 25% and 30% replacement level.
Abstract: Age and sex are biological terms that are socioculturally
constructed for marriage and marital sexual behavior in
every society. Marriage is a universal norm that makes legitimate
sexual behavior between a man and a woman in marital life cycle to
gain bio-social purposes. Cross-cultural studies reveal that marital
sexual frequency as a part of marital sexual behavior not only varies
within the couple-s life cycle, but also varies between and among
couples in diverse cultures. The purpose of the study was to compare
marital sexual frequency in association with age status and length of
marital relationship between Muslim and Santal couples in rural
Bangladesh. For this we assumed that (1) Santal culture compared to
Muslim culture preferred earlier age at marriage for meeting marital
sexual purposes in rural Bangladesh; (2) Marital duration among the
Muslim couples was higher than that among the Santal couples; (3)
Sexual frequency among the younger couples in both the ethnic
communities was higher than the older couples; (4) Sexual frequency
across the Muslim couples- marital life cycle was higher than that the
Santal couples- marital life cycle. In so doing, 288 active couples
(145 for Muslim and 143 for Santal) selected by cluster random
sampling were interviewed with questionnaire method. The findings
of Independent Samples T Test on age at marriage, current age,
marital duration and sexual frequency independently reveal that there
were significant differences in sexual frequency not only across the
couples- life cycle but also vary between the Muslim and Santal
couples in relation to marital duration. The results of Pearson-s Inter-
Correlation Coefficients reveal that although age at marriage, current
age and marital duration for husband and wife were significantly
positive correlated with each other between the communities, there
were significantly negative correlation between the age at marriage,
current age, marital duration and sexual frequency among the
selected couples between the communities.
Abstract: Existing work in temporal logic on representing the
execution of infinitely many transactions, uses linear-time temporal
logic (LTL) and only models two-step transactions. In this paper,
we use the comparatively efficient branching-time computational tree
logic CTL and extend the transaction model to a class of multistep
transactions, by introducing distinguished propositional variables
to represent the read and write steps of n multi-step transactions
accessing m data items infinitely many times. We prove that the
well known correspondence between acyclicity of conflict graphs
and serializability for finite schedules, extends to infinite schedules.
Furthermore, in the case of transactions accessing the same set of
data items in (possibly) different orders, serializability corresponds
to the absence of cycles of length two. This result is used to give an
efficient encoding of the serializability condition into CTL.
Abstract: A numerical analysis of wave and hydrodynamic models
is used to investigate the influence of WAve and Storm Surge
(WASS) in the regional and coastal zones. The numerical analyzed
system consists of the WAve Model Cycle 4 (WAMC4) and the
Princeton Ocean Model (POM) which used to solve the energy
balance and primitive equations respectively. The results of both
models presented the incorporated surface wave in the regional
zone affected the coastal storm surge zone. Specifically, the results
indicated that the WASS generally under the approximation is not
only the peak surge but also the coastal water level drop which
can also cause substantial impact on the coastal environment. The
wave–induced surface stress affected the storm surge can significantly
improve storm surge prediction. Finally, the calibration of wave
module according to the minimum error of the significant wave height
(Hs) is not necessarily result in the optimum wave module in the
WASS analyzed system for the WASS prediction.
Abstract: Plastic waste is a big issue in Thailand, but the amount of recycled plastic in Thailand is still low due to the high investment and operating cost. Hence, the rest of plastic waste are burnt to destroy or sent to the landfills. In order to be financial viable, an effective reverse logistics infrastructure is required to support the product recovery activities. However, there is a conflict between reducing the cost and raising environmental protection level. The purpose of this study is to build a goal programming (GP) so that it can be used to help analyze the proper planning of the Thailand-s plastic recycling system that involves multiple objectives. This study considers three objectives; reducing total cost, increasing the amount of plastic recovery, and raising the desired plastic materials in recycling process. The results from two priority structures show that it is necessary to raise the total cost budget in order to achieve targets on amount of recycled plastic and desired plastic materials.
Abstract: The turbulent mixing of coolant streams of different
temperature and density can cause severe temperature fluctuations in
piping systems in nuclear reactors. In certain periodic contraction
cycles these conditions lead to thermal fatigue. The resulting aging
effect prompts investigation in how the mixing of flows over a sharp
temperature/density interface evolves. To study the fundamental
turbulent mixing phenomena in the presence of density gradients,
isokinetic (shear-free) mixing experiments are performed in a square
channel with Reynolds numbers ranging from 2-500 to 60-000.
Sucrose is used to create the density difference. A Wire Mesh Sensor
(WMS) is used to determine the concentration map of the flow in the
cross section. The mean interface width as a function of velocity,
density difference and distance from the mixing point are analyzed
based on traditional methods chosen for the purposes of
atmospheric/oceanic stratification analyses. A definition of the
mixing layer thickness more appropriate to thermal fatigue and based
on mixedness is devised. This definition shows that the thermal
fatigue risk assessed using simple mixing layer growth can be
misleading and why an approach that separates the effects of large
scale (turbulent) and small scale (molecular) mixing is necessary.
Abstract: In the current research, neuro-fuzzy model and regression model was developed to predict Material Removal Rate in Electrical Discharge Machining process for AISI D2 tool steel with copper electrode. Extensive experiments were conducted with various levels of discharge current, pulse duration and duty cycle. The experimental data are split into two sets, one for training and the other for validation of the model. The training data were used to develop the above models and the test data, which was not used earlier to develop these models were used for validation the models. Subsequently, the models are compared. It was found that the predicted and experimental results were in good agreement and the coefficients of correlation were found to be 0.999 and 0.974 for neuro fuzzy and regression model respectively
Abstract: Influence of octane and benzene on plant cell
ultrastructure and enzymes of basic metabolism, such as nitrogen
assimilation and energy generation have been studied. Different
plants: perennial ryegrass (Lolium perenne) and alfalfa (Medicago
sativa); crops- maize (Zea mays L.) and bean (Phaseolus vulgaris);
shrubs – privet (Ligustrum sempervirens) and trifoliate orange
(Poncirus trifoliate); trees - poplar (Populus deltoides) and white
mulberry (Morus alba L.) were exposed to hydrocarbons of different
concentrations (1, 10 and 100 mM). Destructive changes in bean and
maize leaves cells ultrastructure under the influence of benzene
vapour were revealed at the level of photosynthetic and energy
generation subcellular organells. Different deviations at the level of
subcellular organelles structure and distribution were observed in
alfalfa and ryegrass root cells under the influence of benzene and
octane, absorbed through roots. The level of destructive changes is
concentration dependent. Benzene at low 1 and 10 mM concentration
caused the increase in glutamate dehydrogenase (GDH) activity in
maize roots and leaves and in poplar and mulberry shoots, though to
higher extent in case of lower, 1mM concentration. The induction
was more intensive in plant roots. The highest tested 100mM
concentration of benzene was inhibitory to the enzyme in all plants.
Octane caused induction of GDH in all grassy plants at all tested
concentrations; however the rate of induction decreased parallel to
increase of the hydrocarbon concentration. Octane at concentration 1
mM caused induction of GDH in privet, trifoliate and white mulberry
shoots. The highest, 100mM octane was characterized by inhibitory
effect to GDH activity in all plants. Octane had inductive effect on
malate dehydrogenase in almost all plants and tested concentrations,
indicating the intensification of Trycarboxylic Acid Cycle.
The data could be suggested for elaboration of criteria for plant
selection for phytoremediation of oil hydrocarbons contaminated
soils.
Abstract: This paper presents the experimental results of silicone rubber polymer insulators for 22 kV systems under salt water dip wheel test based on IEC 62217. Straight shed silicone rubber polymer insulators having leakage distance 685 mm were tested continuously 30,000 cycles. One test cycle includes 4 positions, energized, de-energized, salt water dip and deenergized, respectively. For one test cycle, each test specimen remains stationary for about 40 second in each position and takes 8 second for rotate to next position. By visual observation, sever surface erosion was observed on the trunk near the energized end of tested specimen. Puncture was observed on the upper shed near the energized end. In addition, decreasing in hydrophobicity and increasing in hardness were measured on tested specimen comparing with new specimen. Furthermore, chemical analysis by ATR-FTIR was conducted in order to elucidate the chemical change of tested specimens comparing with new specimen.