Abstract: Low volume roads are widely used all over the world. To improve their quality the computer simulation of their behavior is proposed. The FEM model enables to determine stress and displacement conditions in the pavement and/or also in the particular material layers. Different variants of pavement layers, material used, humidity as well as loading conditions can be studied. Among others, the input information about material properties of individual layers made from recycled materials is crucial for obtaining results as exact as possible. For this purpose the cyclic-load triaxial test machine testing of cyclic-load performance of materials is a promising test method. The test is able to simulate the real traffic loading on particular materials taking into account the changes in the horizontal stress conditions produced in particular layers by crossings of vehicles. Also the test specimen can be prepared with different amount of water. Thus modulus of elasticity (Young modulus) of different materials including recycled ones can be measured under the different conditions of horizontal and vertical stresses as well as under the different humidity conditions. Using the proposed testing procedure the modulus of elasticity of recycled materials used in the newly built low volume road is obtained under different stress and humidity conditions set to standard, dry and fully saturated level. Obtained values of modulus of elasticity are used in FEA.
Abstract: Motion capture devices have been utilized in
producing several contents, such as movies and video games. However,
since motion capture devices are expensive and inconvenient to use,
motions segmented from captured data was recycled and synthesized
to utilize it in another contents, but the motions were generally
segmented by contents producers in manual. Therefore, automatic
motion segmentation is recently getting a lot of attentions. Previous
approaches are divided into on-line and off-line, where on-line
approaches segment motions based on similarities between
neighboring frames and off-line approaches segment motions by
capturing the global characteristics in feature space. In this paper, we
propose a graph-based high-level motion segmentation method. Since
high-level motions consist of several repeated frames within temporal
distances, we consider all similarities among all frames within the
temporal distance. This is achieved by constructing a graph, where
each vertex represents a frame and the edges between the frames are
weighted by their similarity. Then, normalized cuts algorithm is used
to partition the constructed graph into several sub-graphs by globally
finding minimum cuts. In the experiments, the results using the
proposed method showed better performance than PCA-based method
in on-line and GMM-based method in off-line, as the proposed method
globally segment motions from the graph constructed based
similarities between neighboring frames as well as similarities among
all frames within temporal distances.
Abstract: the effects of refining and alkaline chemicals on potential of recycling bleached chemical pulp of bagasse were investigated in this study. Recycling was done until three times. Handsheet properties such as, apparent density, light scattering coefficient, tear index, burst index, breaking length, and fold number according to TAPPI standard were measured. Water retention value also was used to considering the treatments during recycling. Refining enhanced the strength of recycled pulp by increasing fiber flexibility and swelling ability, whereas by applying chemical treatment didn't observe any improvement. The morphology of recycled fiber was considered with scanning electron microscopy (SEM).
Abstract: In industrial scale of Gas to Liquid (GTL) process in
Fischer-Tropsch (FT) synthesis, a part of reactor outlet gases such as
CO2 and CH4 as side reaction products, is usually recycled. In this
study, the influence of CO2 and CH4 on the performance and
selectivity of Co-Ru/Al2O3 catalyst is investigated by injection of
these gases (0-20 vol. % of feed) to the feed stream. The effect of
temperature and feed flow rate, are also inspected. The results show
that low amounts of CO2 in the feed stream, doesn`t change the
catalyst activity significantly but increasing the amount of CO2 (more
than 10 vol. %) cause the CO conversion to decrease and the
selectivity of heavy components to increase. Methane acts as an inert
gas and doesn`t affect the catalyst performance. Increasing feed flow
rate has negative effect on both CO conversion and heavy component
selectivity. By raising the temperature, CO conversion will increase
but there are more volatile components in the product. The effect of
CO2 on the catalyst deactivation is also investigated carefully and a
mechanism is suggested to explain the negative influence of CO2 on
catalyst deactivation.
Abstract: This research studied about green logistics and the
expected benefit that organization gotten when adapted to green
logistics also the organization concerned about the important activity
in green logistics to apply in implementation from study was found
that the benefit of green logistics that organization was gotten by
logistics management which was the increased efficiency process of
management the product from producer to customer all of reduce
production cost, increased value added save energy and prevented
environment together
From study was found that the organization had green logistics to
apply in logistics activities in supply chain since downstream till
upstream to prevent environment as follow 1). Purchasing process,
trade facilitation enhance such as linking of information technology
during business to business (B2B business). 2). Productions process
improved by business logistics improvement 3). Warehouse
management process such as recycled packaging, moving goods in to
warehouse, transportation goods and inside receiving and delivery
products plan.
Abstract: This research studied recycled waste by the Recyclable Material Bank Project of 4 universities in the central region of Thailand for the evaluation of reducing greenhouse gas emissions compared with landfilling activity during July 2012 to June 2013. The results showed that the projects collected total amount of recyclable wastes of about 911,984.80 kilograms. Office paper had the largest amount among these recycled wastes (50.68% of total recycled waste). 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 gas emissions equivalent to about 2814.969 metric tons of carbon dioxide. The most significant recycled waste that affects the reduction of greenhouse gas emissions is office paper which is 70.16% 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, metals, mixed recyclables, and glass, respectively.
Abstract: Climate change and environmental pressures are
major international issues nowadays. It is time when governments,
businesses and consumers have to respond through more
environmentally friendly and aware practices, products and policies.
This is the prime time to develop alternative sustainable construction
materials, reduce greenhouse gas emissions, save energy, look to
renewable energy sources and recycled materials, and reduce waste.
The utilization of waste materials (slag, fly ash, glass beads, plastic
and so on) in concrete manufacturing is significant due to its
engineering, financial, environmental and ecological benefits. Thus,
utilization of waste materials in concrete production is very much
helpful to reach the goal of the sustainable construction. Therefore,
this study intends to use glass beads in concrete production.
The paper reports on the performance of 9 different concrete
mixes containing different ratios of glass crushed to 5 mm - 20 mm
maximum size and glass marble of 20 mm size as coarse aggregate.
Ordinary Portland cement type 1 and fine sand less than 0.5 mm were
used to produce standard concrete cylinders. Compressive strength
tests were carried out on concrete specimens at various ages. Test
results indicated that the mix having the balanced ratio of glass beads
and round marbles possess maximum compressive strength which is
3889 psi, as glass beads perform better in bond formation but have
lower strength, on the other hand marbles are strong in themselves
but not good in bonding. These mixes were prepared following a
specific W/C and aggregate ratio; more strength can be expected to
achieve from different W/C, aggregate ratios, adding admixtures like
strength increasing agents, ASR inhibitor agents etc.
Abstract: In this study two series of self compacting concrete
mixtures were prepared with 100% coarse recycled concrete
aggregates and different percentages of 0%, 20%, 40%, 60%, 80%
and 100% fine recycled concrete aggregates. In series I and II the
water to binder ratios were 0.50 and 0.45, respectively. The cement
content was kept 350
3 m
kg for those mixtures that don't have any
Nano-Silica. To improve the compressive strength of samples, Nano-
Silica replaced with 10% of cement weight in concrete mixtures. By
doing the tests, the results showed that, adding Nano-silica to the
samples with less percentage of fine recycled concrete aggregates,
lead to more increase on the compressive strength.
Abstract: This paper presented a novel combined cycle of air separation and natural gas liquefaction. The idea is that natural gas can be liquefied, meanwhile gaseous or liquid nitrogen and oxygen are produced in one combined cryogenic system. Cycle simulation and exergy analysis were performed to evaluate the process and thereby reveal the influence of the crucial parameter, i.e., flow rate ratio through two stages expanders β on heat transfer temperature difference, its distribution and consequent exergy loss. Composite curves for the combined hot streams (feeding natural gas and recycled nitrogen) and the cold stream showed the degree of optimization available in this process if appropriate β was designed. The results indicated that increasing β reduces temperature difference and exergy loss in heat exchange process. However, the maximum limit value of β should be confined in terms of minimum temperature difference proposed in heat exchanger design standard and heat exchanger size. The optimal βopt under different operation conditions corresponding to the required minimum temperature differences was investigated.
Abstract: There has been a growing interest in utilizing surfactants in remediation processes to separate the hydrophobic volatile organic compounds (HVOCs) from aqueous solution. One attractive process is cloud point extraction (CPE), which utilizes nonionic surfactants as a separating agent. Since the surfactant cost is a key determination of the economic viability of the process, it is important that the surfactants are recycled and reused. This work aims to study the performance of the co-current vacuum stripping using a packed column for HVOCs removal from contaminated surfactant solution. Six types HVOCs are selected as contaminants. The studied surfactant is the branched secondary alcohol ethoxylates (AEs), Tergitol TMN-6 (C14H30O2). The volatility and the solubility of HVOCs in surfactant system are determined in terms of an apparent Henry’s law constant and a solubilization constant, respectively. Moreover, the HVOCs removal efficiency of vacuum stripping column is assessed in terms of percentage of HVOCs removal and the overall liquid phase volumetric mass transfer coefficient. The apparent Henry’s law constant of benzenz , toluene, and ethyl benzene were 7.00×10-5, 5.38×10-5, 3.35× 10-5 respectively. The solubilization constant of benzene, toluene, and ethyl benzene were 1.71, 2.68, 7.54 respectively. The HVOCs removal for all solute were around 90 percent.
Abstract: A green design for assembly model is presented to
integrate design evaluation and assembly and disassembly sequence
planning by evaluating the three activities in one integrated model. For
an assembled product, an assembly sequence planning model is
required for assembling the product at the start of the product life cycle.
A disassembly sequence planning model is needed for disassembling
the product at the end. In a green product life cycle, it is important to
plan how a product can be disassembled, reused, or recycled, before
the product is actually assembled and produced. Given a product
requirement, there may be several design alternative cases to design
the same product. In the different design cases, the assembly and
disassembly sequences for producing the product can be different. In
this research, a new model is presented to concurrently evaluate the
design and plan the assembly and disassembly sequences. First, the
components are represented by using graph based models. Next, a
particle swarm optimization (PSO) method with a new encoding
scheme is developed. In the new PSO encoding scheme, a particle is
represented by a position matrix defining an assembly sequence and a
disassembly sequence. The assembly and disassembly sequences can
be simultaneously planned with an objective of minimizing the total of
assembly costs and disassembly costs. The test results show that the
presented method is feasible and efficient for solving the integrated
design evaluation and assembly and disassembly sequence planning
problem. An example product is implemented and illustrated in this
paper.
Abstract: In recent years demolished concrete waste handling and management is the new primary challenging issue faced by the countries all over the world. It is very challenging and hectic problem that has to be tackled in an indigenous manner, it is desirable to completely recycle demolished concrete waste in order to protect natural resources and reduce environmental pollution. In this research paper an experimental study is carried out to investigate the feasibility and recycling of demolished waste concrete for new construction. The present investigation to be focused on recycling demolished waste materials in order to reduce construction cost and resolving housing problems faced by the low income communities of the world. The crushed demolished concrete wastes is segregated by sieving to obtain required sizes of aggregate, several tests were conducted to determine the aggregate properties before recycling it into new concrete. This research shows that the recycled aggregate that are obtained from site make good quality concrete. The compressive strength test results of partial replacement and full recycled aggregate concrete and are found to be higher than the compressive strength of normal concrete with new aggregate.
Abstract: As the resources for naturally occurring aggregates
diminished at an ever increasing rate, researchers are keen to utilize
recycled materials in road construction in harmony with sustainable
development. Steel slag, a waste product from the steel making
industry, is one of the recycled materials reported to exhibit great
potential to replace naturally occurring aggregates in asphalt
mixtures. This paper presents the resilient modulus properties of
steel slag asphalt mixtures subjected to short term oven ageing
(STOA). The resilient modulus test was carried out to evaluate the
stiffness of asphalt mixtures at 10ºC, 25ºC and 40ºC. Previous
studies showed that stiffness changes in asphalt mixture played an
important role in inflicting pavement distress particularly cracking
and rutting that are common at low and high temperatures
respectively. Temperature was found to significantly influence the
resilient modulus of asphalt mixes. The resilient modulus of the
asphalt specimens tested decreased by more than 90% when the test
temperature increased from 10°C to 40°C.
Abstract: The recycling of concrete, bricks and masonry rubble
as concrete aggregates is an important way to contribute to a
sustainable material flow. However, there are still various
uncertainties limiting the widespread use of Recycled Concrete
Aggregates (RCA). The fluctuations in the composition of grade
recycled aggregates and their influence on the properties of fresh and
hardened concrete are of particular concern regarding the use of
RCA. Most of problems occurring while using recycled concrete
aggregates as aggregates are due to higher porosity and hence higher
water absorption, lower mechanical strengths, residual impurities on
the surface of the RCA forming weaker bond between cement paste
and aggregate. So, the reuse of RCA is still limited. Efficient
polymer based treatment is proposed in order to reuse RCA easier.
The silicon-based polymer treatments of RCA were carried out and
were compared. This kind of treatment can improve the properties of
RCA such as the rate of water absorption on treated RCA is
significantly reduced.
Abstract: This paper reports on the influence of surface-treated coarse recycled concrete aggregate (RCA) on developing the compressive strength of concrete. The coarse RCA was initially treated by separately impregnating it in calcium metasilicate (CM) or wollastonite and nanosilica (NS) prepared at various concentrations. The effects of both treatment materials on concrete properties (e.g., slump, density and compressive strength) were evaluated. Scanning electron microscopy (SEM) analysis was performed to examine the microstructure of the resulting concrete. Results show that the effective use of treated coarse RCA significantly enhances the compressive strength of concrete. This result is supported by the SEM analysis, which indicates the formation of a dense interface between the treated coarse RCA and the cement matrix. Coarse RCA impregnated in CM solution results in better concrete strength than NS, and the optimum concentration of CM solution recommended for treated coarse RCA is 10%.
Abstract: Recycling of aluminum alloys often decrease fluidity,
consequently influence the castability of the alloy. In this study, the
fluidity of Al-Zn alloys, such as the standard A713 alloy with and
without scrap addition has been investigated. The scrap added was
comprised of contaminated alloy turning chips. Fluidity
measurements were performed with double spiral fluidity test
consisting of gravity casting of double spirals in green sand moulds
with good reproducibility. The influence of recycled alloy on fluidity
has been compared with that of the virgin alloy and the results
showed that the fluidity decreased with the increase in recycled alloy
at minimum pouring temperatures. Interestingly, an appreciable
improvement in the fluidity was observed at maximum pouring
temperature, especially for coated spirals.
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 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: 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 main aim of this research is to study the possible
use of recycled fine aggregate made from waste rubble wall to
substitute partially for the natural sand used in the production of
cement and sand bricks. The bricks specimens were prepared by
using 100% natural sand; they were then replaced by recycled fine
aggregate at 25, 50, 75, and 100% by weight of natural sand. A series
of tests was carried out to study the effect of using recycled aggregate
on the physical and mechanical properties of bricks, such as density,
drying shrinkage, water absorption characteristic, compressive and
flexural strength. Test results indicate that it is possible to
manufacture bricks containing recycled fine aggregate with good
characteristics that are similar in physical and mechanical properties
to those of bricks with natural aggregate, provided that the percentage
of recycled fine aggregates is limited up to 50-75%.