Abstract: In Algeria, the conditioning units of dates, generate
significant quantities of waste arising from sorting deviations. This
biomass, until then considered as a waste with high impact on the
environment can be transformed into high value added product. It is
possible to develop common dates of low commercial value, and put
on the local and international market a new generation of products
with high added values such as bio ethanol. Besides its use in
chemical synthesis, bio ethanol can be blended with gasoline to
produce a clean fuel while improving the octane.
Abstract: This study investigates the influence of low
temperature thermo-chemical pretreatment of organic food waste on
performance of COD solubilisation. Both temperature and alkaline
agent were reported to have effect on solubilizing any possible
biomass including organic food waste. The three independent
variables considered in this pretreatment were temperature (50-90oC),
pretreatment time (30-120 minutes) and alkaline concentration,
sodium hydroxide, NaOH (0.7-15 g/L). The maximal condition
obtained were 90oC, 15 g/L NaOH for 2 hours. Solubilisation has
potential in enhancing methane production by providing high amount
of soluble components at early stage during anaerobic digestion.
Abstract: Within this paper, latest results on processing of energetic nanomaterials by means of the Spray Flash Evaporation technique are presented. This technology constitutes a highly effective and continuous way to prepare fascinating materials on the nano- and micro-scale. Within the process, a solution is set under high pressure and sprayed into an evacuated atomization chamber. Subsequent ultrafast evaporation of the solvent leads to an aerosol stream, which is separated by cyclones or filters. No drying gas is required, so the present technique should not be confused with spray dying. Resulting nanothermites, insensitive explosives or propellants and compositions are foreseen to replace toxic (according to REACH) and very sensitive matter in military and civil applications. Diverse examples are given in detail: nano-RDX (n-Cyclotrimethylentrinitramin) and nano-aluminum based systems, mixtures (n-RDX/n-TNT - trinitrotoluene) or even cocrystalline matter like n-CL-20/HMX (Hexanitrohexaazaisowurtzitane/ Cyclotetra-methylentetranitramin). These nanomaterials show reduced sensitivity by trend without losing effectiveness and performance. An analytical study for material characterization was performed by using Atomic Force Microscopy, X-Ray Diffraction, and combined techniques as well as spectroscopic methods. As a matter of course, sensitivity tests regarding electrostatic discharge, impact, and friction are provided.
Abstract: The agenda of showing the scheduled time for
performing certain tasks is known as timetabling. It is widely used in
many departments such as transportation, education, and production.
Some difficulties arise to ensure all tasks happen in the time and
place allocated. Therefore, many researchers invented various
programming models to solve the scheduling problems from several
fields. However, the studies in developing the general integer
programming model for many timetabling problems are still
questionable. Meanwhile, this thesis describes about creating a
general model which solves different types of timetabling problems
by considering the basic constraints. Initially, the common basic
constraints from five different fields are selected and analyzed. A
general basic integer programming model was created and then
verified by using the medium set of data obtained randomly which is
much similar to realistic data. The mathematical software, AIMMS
with CPLEX as a solver has been used to solve the model. The model
obtained is significant in solving many timetabling problems easily
since it is modifiable to all types of scheduling problems which have
same basic constraints.
Abstract: Anaerobic digestion is a well-known technique for
sustainable energy recovery from sewage sludge. However, sewage
sludge digestion is restricted due to certain factors. Pre-treatment
methods have been established in various publications as a promising
technique to improve the digestibility of the sewage sludge and to
enhance the biogas generated which can be used for energy recovery.
In this study, continuous flow microwave (MW) pre-treatment with
different intensities were compared by using 5 L semi-continuous
digesters at a hydraulic retention time of 27 days. We focused on the
effects of MW at different intensities on the sludge solubilization,
sludge digestibility, and biogas production of the untreated and MW
pre-treated sludge. The MW pre-treatment demonstrated an increase
in the ratio of soluble chemical oxygen demand to total chemical
oxygen demand (sCOD/tCOD) and volatile fatty acid (VFA)
concentration. Besides that, the total volatile solid (TVS) removal
efficiency and tCOD removal efficiency also increased during the
digestion of the MW pre-treated sewage sludge compared to the
untreated sewage sludge. Furthermore, the biogas yield also
subsequently increases due to the pre-treatment effect. A higher MW
power level and irradiation time generally enhanced the biogas
generation which has potential for sustainable energy recovery from
sewage treatment plant. However, the net energy balance tabulation
shows that the MW pre-treatment leads to negative net energy production.
Abstract: Within Rapid Prototyping technologies are used many
types of materials. Many of them are recyclable but there are still as
plastic like, so practically they do not degrade in the landfill.
Polylactic acid (PLA) is one of the special plastic materials, which
are biodegradable and available for 3D printing within Fused
Deposition Modeling (FDM) technology. The question is, if the
mechanical properties of produced models are comparable to similar
technical plastic materials which are usual for prototype production.
Presented paper shows the experiments results for tensile strength
measurements for specimens prepared with different 3D printer
settings and model orientation. Paper contains also the comparison of
tensile strength values with values measured on specimens produced
by conventional technologies as injection moulding.
Abstract: Broiler slaughter waste has become a major source of
pollution throughout the world. Utilization of broiler slaughter waste
by dry rendering process produced Rendered Chicken Oil (RCO), a
cheap raw material for biodiesel production and Carcass Meal a feed
ingredient for pets and fishes. Conversion of RCO into biodiesel may
open new vistas for generating wealth from waste besides controlling
the major havoc of environmental pollution. A two-step process to
convert RCO to good quality Biodiesel was invented. Acid catalysed
esterification of FFA followed by base catalysed transesterification of
triglycerides was carried out after meticulously standardizing the
methanol molar ratio, catalyst concentration, reaction temperature,
and reaction time to obtain the maximum biodiesel yield of 97.62%
and lowest glycerol yield of 6.96%. RCO biodiesel blend was tested
in a CRDI diesel engine. The results revealed that the blending of
commercial diesel with 20% RCO biodiesel (B20) lead to less engine
wear, a quieter engine and better fuel economy. The better lubricating
qualities of RCO B20 prevented over heating of engine, which
prolongs the engine life. RCO B20 can reduce the import of crude oil
and substantially reduce the engine emissions as proved by
significantly lower smoke levels, thus mitigating climatic changes.
Abstract: This paper is concerned with the ways in which
Assisted Reproductive Technologies (ARTs) affect women’s lives
and perceptions regarding their infertility, contraception and
reproductive health. The paper is based on a qualitative feminist
survey study to explore and analyze issues arising from the use of
ARTs by women in New Delhi, the capital of India. A rapid growth in
the number of fertility clinics has been noticed recently. A critical
analysis of interviews revealed that these technologies are used and
developed for making profits at the cost of women’s lives. In this
way, these technologies are influencing and changing the traditional
patterns of motherhood requiring a rethinking about new ways of
reproduction introduced through the use of ARTs.
Abstract: The plastic industry plays very important role in the
economy of any country. It is generally among the leading share of
the economy of the country. Since metals and their alloys are very
rarely available on the earth. Therefore, to produce plastic products
and components, which finds application in many industrial as well
as household consumer products is beneficial. Since 50% plastic
products are manufactured by injection moulding process. For
production of better quality product, we have to control quality
characteristics and performance of the product. The process
parameters plays a significant role in production of plastic, hence the
control of process parameter is essential. In this paper the effect of
the parameters selection on injection moulding process has been
described. It is to define suitable parameters in producing plastic
product. Selecting the process parameter by trial and error is neither
desirable nor acceptable, as it is often tends to increase the cost and
time. Hence, optimization of processing parameter of injection
moulding process is essential. The experiments were designed with
Taguchi’s orthogonal array to achieve the result with least number of
experiments. Plastic material polypropylene is studied. Tensile
strength test of material is done on universal testing machine, which
is produced by injection moulding machine. By using Taguchi
technique with the help of MiniTab-14 software the best value of
injection pressure, melt temperature, packing pressure and packing
time is obtained. We found that process parameter packing pressure
contribute more in production of good tensile plastic product.
Abstract: A method of effective planning and control of
industrial facility energy consumption is offered. The method allows
optimally arranging the management and full control of complex
production facilities in accordance with the criteria of minimal
technical and economic losses at the forecasting control. The method
is based on the optimal construction of the power efficiency
characteristics with the prescribed accuracy. The problem of optimal
designing of the forecasting model is solved on the basis of three
criteria: maximizing the weighted sum of the points of forecasting
with the prescribed accuracy; the solving of the problem by the
standard principles at the incomplete statistic data on the basis of
minimization of the regularized function; minimizing the technical
and economic losses due to the forecasting errors.
Abstract: In order to be competitive, companies have to reduce
their production costs while meeting increasing quality requirements.
Therefore, companies try to plan their assembly processes as detailed
as possible. However, increasing product individualization leading to
a higher number of variants, smaller batch sizes and shorter product
life cycles raise the question to what extent the effort of detailed
planning is still justified. An important approach in this field of
research is the concept of determining the economic planning depth
for assembly process planning based on production specific
influencing factors. In this paper first solution hypotheses as well as a
first draft of the resulting method will be presented.
Abstract: The purpose of this paper is to contribute to the
enhancement of a hydroelectric plant protection by coordinating
protection measures / existing security and introducing new measures
under a risk management process. In addition, plan identifies key
critical elements of a hydroelectric plant, from its level vulnerabilities
and threats it is subjected to in order to achieve the necessary
protection measures to reduce the level of risk.
Abstract: Large-scale machine tools for the manufacturing of
large work pieces, e.g. blades, casings or gears for wind turbines,
feature pose-dependent dynamic behavior. Small structural damping
coefficients lead to long decay times for structural vibrations that
have negative impacts on the production process. Typically, these
vibrations are handled by increasing the stiffness of the structure by
adding mass. This is counterproductive to the needs of sustainable
manufacturing as it leads to higher resource consumption both in
material and in energy. Recent research activities have led to higher
resource efficiency by radical mass reduction that is based on controlintegrated
active vibration avoidance and damping methods. These
control methods depend on information describing the dynamic
behavior of the controlled machine tools in order to tune the
avoidance or reduction method parameters according to the current
state of the machine. This paper presents the appearance, consequences and challenges
of the pose-dependent dynamic behavior of lightweight large-scale
machine tool structures in production. It starts with the theoretical
introduction of the challenges of lightweight machine tool structures
resulting from reduced stiffness. The statement of the pose-dependent
dynamic behavior is corroborated by the results of the experimental
modal analysis of a lightweight test structure. Afterwards, the
consequences of the pose-dependent dynamic behavior of lightweight
machine tool structures for the use of active control and vibration
reduction methods are explained. Based on the state of the art of
pose-dependent dynamic machine tool models and the modal
investigation of an FE-model of the lightweight test structure, the
criteria for a pose-dependent model for use in vibration reduction are
derived. The description of the approach for a general posedependent
model of the dynamic behavior of large lightweight
machine tools that provides the necessary input to the aforementioned
vibration avoidance and reduction methods to properly tackle
machine vibrations is the outlook of the paper.
Abstract: Paper deals with the modeling and simulation of energy consumption and GHG production of two different modes of regional passenger transport – road and railway. These two transport modes use the same type of fuel – diesel. Modeling and simulation of the energy consumption in transport is often used due to calculation satisfactory accuracy and cost efficiency. Paper deals with the calculation based on EN standards and information collected from technical information from vehicle producers and characteristics of tracks. Calculation included maximal theoretical capacity of bus and train and real passenger’s measurement from operation. Final energy consumption and GHG production is calculated by using software simulation. In evaluation of the simulation is used system “well to wheel”.
Abstract: The article includes the results and conclusions from
empirical researches that had been done. The research focuses on the
impact of investments made in small and medium-sized enterprises
financed from EU funds on the competitiveness of these companies.
The researches includes financial results in sales revenue and net
income, expenses, and many other new products/services on offer,
higher quality products and services, more modern methods of
production, innovation in management processes, increase in the
number of customers, increase in market share, increase in
profitability of production and provision of services. The main
conclusions are that, companies with direct investments under this
measure shall apply the modern methods of production. The
consequence of this is to increase the quality of our products and
services. Furthermore, both small and medium-sized enterprises have
introduced new products and services. Investments were carried out,
thus enabling better work organization in enterprises. Entrepreneurs
would guarantee higher quality of service, which would result in
better relationships with their customers, what is more, noting the rise
in number of clients. More than half of the companies indicated that
the investments contributed to the increase in market share. Same
thing as for market reach and brand recognition of particular
company. An interesting finding is that, investments in small
enterprises were more effective than medium-sized enterprises.
Abstract: The purpose of the study was to examine lifelong
education for teachers as a tool for achieving effective teaching and
learning. Lifelong education enhances social inclusion, personal
development, citizenship, employability, teaching and learning,
community and the nation. It is imperative that the teacher needs to
update his knowledge regularly to be able to perform optimally, since
he has a major position in the inculcation of desirable elements in
students, and the challenges of lifelong education were also
discussed. Descriptive survey design was adopted for the study. A
simple random sampling technique was used to select 80 teachers as
sample from a population of 105 senior secondary school teachers in
Makurdi Local Government Area of Benue State. A 20-item self
designed questionnaire subjected to expert validation and reliability
was used to collect data. The reliability Alpha coefficient of 0.87 was
established using Cronbach’s Alpha technique, mean scores and
standard deviation were used to answer the 2 research questions
while chi-square was used to analyse data for the 2 null hypotheses,
which states that lifelong education for teachers is not a significant
tool for achieving effective teaching and lifelong education for
teachers does not significantly impact on effective learning. The
findings of the study revealed that, lifelong education for teachers can
be used as a tool for achieving effective teaching and learning, and
the study recommended among others that government, organizations
and individuals should in collaboration put lifelong education
programmes for teachers on the priority list. The paper concluded
that the strategic position of lifelong education for teachers towards
enhanced teaching, learning and the production of quality manpower
in the society makes it imperative for all hands to be on “deck” to
support the programme financially and otherwise.
Abstract: The use of magnesium alloys is limited due to their
susceptibility to corrosion although they have many attractive
physical and mechanical properties. To increase mechanical and
corrosion properties of these alloys, many deposition method and
coating types are used. Electroless Ni–B coatings have received
considerable interest recently due to its unique properties such as
cost-effectiveness, thickness uniformity, good wear resistance,
lubricity, good ductility and corrosion resistance, excellent
solderability and electrical properties and antibacterial property. In
this study, electroless Ni-B coating could been deposited on AZ91
magnesium alloy. The obtained coating exhibited a harder and
rougher structure than the substrate.
Abstract: The objective of the paper is a numerical study of heat
transfer between perforated metal plates and the surrounding air
flows. Different perforation structures can nowadays be found in
various industrial products. Besides improving the mechanical
properties, the perforations can intensify the heat transfer as well. The
heat transfer coefficient depends on a wide range of parameters such
as type of perforation, size, shape, flow properties of the surrounding
air etc. The paper was focused on three different perforation
structures which have been investigated from the point of the view of
the production in the previous studies. To determine the heat
coefficients and the Nusselt numbers, the numerical simulation
approach was adopted. The calculations were performed using the
OpenFOAM software. The three-dimensional, unstable, turbulent and
incompressible air flow around the perforated surface metal plate was
considered.
Abstract: The garment manufacturing industry involves
sequential processes that are subjected to uncontrollable variations.
The industry depends on the skill of labour in handling the varieties
of fabrics and accessories, machines, as well as complicated sewing
operation. Due to these reasons, garment manufacturers have created
systems to monitor and to control the quality of the products on a
regular basis by conducting quality approaches to minimize variation.
With that, the aim of this research has been to ascertain the quality
approaches deployed by Malaysian garment manufacturers in three
key areas - quality systems and tools; quality control and types of
inspection; as well as sampling procedures chosen for garment
inspection. Besides, the focus of this research was to distinguish the
quality approaches adopted by companies that supplied finished
garments to both domestic and international markets. Feedback from
each company representative has been obtained via online survey,
which comprised of five sections and 44 questions on the
organizational profile and the quality approaches employed in the
garment industry. As a result, the response rate was 31%. The results
revealed that almost all companies have established their own
mechanism of process control by conducting a series of quality
inspections for daily production, either it was formally set up or
otherwise. In addition, quality inspection has been the predominant
quality control activity in the garment manufacturing, while the level
of complexity of these activities was substantially dictated by the
customers. Moreover, AQL-based sampling was utilized by
companies dealing with exports, whilst almost all the companies that
only concentrated on the domestic market were comfortable using
their own sampling procedures for garment inspection. Hence, this
research has provided insights into the implementation of a number
of quality approaches that were perceived as important and useful in
the garment manufacturing sector, which is truly labour-intensive.
Abstract: South Africa is in its post-industrial era moving from
the primary and secondary sector to the tertiary sector. The study
investigated the impact of the disaggregated energy consumption
(coal, oil, and electricity) on the primary, secondary and tertiary
sectors of the economy between 1980 and 2012 in South Africa.
Using vector error correction model, it was established that South
Africa is an energy dependent economy, and that energy (especially
electricity and oil) is a limiting factor of growth. This implies that
implementation of energy conservation policies may hamper
economic growth. Output growth is significantly outpacing energy
supply, which has necessitated load shedding. To meet up the excess
energy demand, there is a need to increase the generating capacity
which will necessitate increased investment in the electricity sector as
well as strategic steps to increase oil production. There is also need to
explore more renewable energy sources, in order to meet the growing
energy demand without compromising growth and environmental
sustainability. Policy makers should also pursue energy efficiency
policies especially at sectoral level of the economy.