Abstract: The substantial development of the construction
industry has forced the cement industry, its major support, to focus
on achieving maximum productivity to meet the growing demand for
this material. This means that the reliability of a cement production
system needs to be at the highest level that can be achieved by good
maintenance. This paper studies the extent to which the
implementation of RCM is needed as a strategy for increasing the
reliability of the production systems component can be increased,
thus ensuring continuous productivity. In a case study of four Libyan
cement factories, 80 employees were surveyed and 12 top and middle
managers interviewed. It is evident that these factories usually
breakdown more often than once per month which has led to a
decline in productivity. In many times they cannot achieve the
minimum level of production amount. This has resulted from the
poor reliability of their production systems as a result of poor or
insufficient maintenance. It has been found that most of the factories’
employees misunderstand maintenance and its importance. The main
cause of this problem is the lack of qualified and trained staff, but in
addition it has been found that most employees are not found to be
motivated as a result of a lack of management support and interest. In
response to these findings, it has been suggested that the RCM
strategy should be implemented in the four factories. The results
show the importance of the development of maintenance strategies
through the implementation of RCM in these factories. The purpose
of it would be to overcome the problems that could secure the
reliability of the production systems. This study could be a useful
source of information for academic researchers and the industrial
organizations which are still experiencing problems in maintenance
practices.
Abstract: This paper presents a method of evaluating the effect
of aggregate angularity on hot mix asphalt (HMA) properties and its
relationship to the Permanent Deformation resistance. The research
concluded that aggregate particle angularity had a significant effect
on the Permanent Deformation performance, and also that with an
increase in coarse aggregate angularity there was an increase in the
resistance of mixes to Permanent Deformation. A comparison
between the measured data and predictive data of permanent
deformation predictive models showed the limits of existing
prediction models. The numerical analysis described the permanent
deformation zones and concluded that angularity has an effect of the
onset of these zones. Prediction of permanent deformation help road
agencies and by extension economists and engineers determine the
best approach for maintenance, rehabilitation, and new construction
works of the road infrastructure.
Abstract: Super steel materials play a vital role in the
construction and fabrication of structural, piping and pipeline
components. In assuring the integrity of onshore and offshore
operating systems, they enable life cycle costs to be minimized. In
this context, Duplex stainless steel (DSS) material related welding on
constructions and fabrications plays a significant role in maintaining
and assuring integrity at an optimal expenditure over the life cycle of
production and process systems as well as associated structures. In
DSS welding, factors such as gap geometry, shielding gas supply
rate, welding current, and type of the welding process are vital to the
final joint performance. Hence, an experimental investigation has
been performed using an engineering robust design approach
(ERDA) to investigate the optimal settings that generate optimal
super DSS (i.e. UNS S32750) joint performance. This manuscript
illustrates the mathematical approach and experimental design,
optimal parameter settings and results of the verification experiment.
Abstract: White concrete facade elements are widely used in
construction industry. It is challenging to achieve the desired
workability in casting of white concrete elements. Particle Matrix
model was used for proportioning the self-compacting white concrete
(SCWC) to control segregation and bleeding and to improve
workability. The paper presents how to reach the target slump flow
while controlling bleeding and segregation in SCWC. The amount of
aggregates, binders and mixing water, as well as type and dosage of
superplasticizer (SP) to be used are the major factors influencing the
properties of SCWC. Slump flow and compressive strength tests were
carried out to examine the performance of SCWC, and the results
indicate that the particle matrix model could produce successfully
SCWC controlling segregation and bleeding.
Abstract: The area of liberty, security and justice within the
European Union is still a work in progress. No one can deny that the
EU struggles between a monistic and a dualist approach.
The aim of our essay is to first review how the European law is
perceived by the rest of the international scene. It will then discuss
two main mechanisms at play: the interpretation of larger
international treaties and the penal mechanisms of European law.
Finally, it will help us understand the role of a penal Europe on the
international scene with concrete examples.
Special attention will be paid to cases that deal with fundamental
rights as they represent an interesting case study in Europe and in the
rest of the World. It could illustrate the aforementioned duality
currently present in the Union’s interpretation of international public
law. On the other hand, it will explore some specific European penal
mechanism through mutual recognition and the European arrest
warrant in the transnational criminality frame.
Concerning the interpretation of the treaties, it will first, underline
the ambiguity and the general nature of some treaties that leave the
EU exposed to tension and misunderstanding then it will review the
validity of an EU act (whether or not it is compatible with the rules of
International law).
Finally, it will focus on the most complete manifestation of liberty,
security and justice through the principle of mutual recognition. Used
initially in commercial matters, it has become “the cornerstone” of
European construction. It will see how it is applied in judicial
decisions (its main event and achieving success is via the European
arrest warrant) and how European member states have managed to
develop this cooperation.
Abstract: Brass terminal, one of the several crude oil and
petroleum products storage/handling facilities in the Niger Delta was
built in the 1980s. Activities at this site, over the years, released
crude oil into this 3 m-deep, 1500 m-long canal lying adjacent to the
terminal with oil floating on it and its sediment heavily polluted. To
ensure effective clean-up, three major activities were planned: site
characterization, bioremediation pilot plant construction and testing
and full-scale bioremediation of contaminated sediment / bank soil by
land farming. The canal was delineated into 12 lots and each
characterized, with reference to the floating oily phase, contaminated
sediment and canal bank soil. As a result of site characterization, a
pilot plant for on-site bioremediation was designed and a treatment
basin constructed for carrying out pilot bioremediation test.
Following a designed sampling protocol, samples from this pilot
plant were collected for analysis at two laboratories as a quality
assurance / quality control check. Results showed that Brass Canal
upstream is contaminated with dark, thick and viscous oily film with
characteristic hydrocarbon smell while downstream, thin oily film
interspersed with water was observed. Sediments were observed to be
dark with mixture of brownish sandy soil with TPH ranging from
17,800 mg/kg in Lot 1 to 88,500 mg/kg in Lot 12 samples. Brass
Canal bank soil was observed to be sandy from ground surface to 3m,
below ground surface (bgs) it was silty-sandy and brownish while
subsurface soil (4-10m bgs) was sandy-clayey and whitish/grayish
with typical hydrocarbon smell. Preliminary results obtained so far
have been very promising but were proprietary. This project is
considered, to the best of technical literature knowledge, the first
large-scale on-site bioremediation project in the Niger Delta region,
Nigeria.
Abstract: This paper examines the utilization of public-private
partnerships for the building and operation of wastewater treatment
plants. Our research focuses on risk allocation in this kind of projects.
Our analysis builds on more than hundred wastewater treatment
plants built and operated through PPP projects in Aragon (Spain).
The paper illustrates the consequences of an inadequate management
of construction risk and an unsuitable transfer of demand risk in
wastewater treatment plants. It also shows that the involvement of
many public bodies at local, regional and national level further
increases the complexity of this kind of projects and make time
delays more likely.
Abstract: The aim of this paper is to present the concept of an
agile enterprise model and to initiate discussion on the research
assumptions of the model presented. The implementation of the
research project "The agility of enterprises in the process of adapting
to the environment and its changes" began in August 2014 and is
planned to last three years. The article has the form of a work-inprogress
paper which aims to verify and initiate a debate over the
proposed research model. In the literature there are very few
publications relating to research into agility; it can be concluded that
the most controversial issue in this regard is the method of measuring
agility. In previous studies the operationalization of agility was often
fragmentary, focusing only on selected areas of agility, for example
manufacturing, or analysing only selected sectors. As a result the
measures created to date can only be treated as contributory to the
development of precise measurement tools. This research project
aims to fill a cognitive gap in the literature with regard to the
conceptualization and operationalization of an agile company. Thus,
the original contribution of the author of this project is the
construction of a theoretical model that integrates manufacturing
agility (consisting mainly in adaptation to the environment) and
strategic agility (based on proactive measures). The author of this
research project is primarily interested in the attributes of an agile
enterprise which indicate that the company is able to rapidly adapt to
changing circumstances and behave pro-actively.
Abstract: A simple adaptive voice activity detector (VAD) is
implemented using Gabor and gammatone atomic decomposition of
speech for high Gaussian noise environments. Matching pursuit is
used for atomic decomposition, and is shown to achieve optimal
speech detection capability at high data compression rates for low
signal to noise ratios. The most active dictionary elements found by
matching pursuit are used for the signal reconstruction so that the
algorithm adapts to the individual speakers dominant time-frequency
characteristics. Speech has a high peak to average ratio enabling
matching pursuit greedy heuristic of highest inner products to isolate
high energy speech components in high noise environments. Gabor
and gammatone atoms are both investigated with identical
logarithmically spaced center frequencies, and similar bandwidths.
The algorithm performs equally well for both Gabor and gammatone
atoms with no significant statistical differences. The algorithm
achieves 70% accuracy at a 0 dB SNR, 90% accuracy at a 5 dB SNR
and 98% accuracy at a 20dB SNR using 30d B SNR as a reference
for voice activity.
Abstract: In this work, we explore the capability of the mean
shift algorithm as a powerful preprocessing tool for improving the
quality of spatial data, acquired from airborne scanners, from densely
built urban areas. On one hand, high resolution image data corrupted
by noise caused by lossy compression techniques are appropriately
smoothed while at the same time preserving the optical edges and, on
the other, low resolution LiDAR data in the form of normalized
Digital Surface Map (nDSM) is upsampled through the joint mean
shift algorithm. Experiments on both the edge-preserving smoothing
and upsampling capabilities using synthetic RGB-z data show that the
mean shift algorithm is superior to bilateral filtering as well as to
other classical smoothing and upsampling algorithms. Application of
the proposed methodology for 3D reconstruction of buildings of a
pilot region of Athens, Greece results in a significant visual
improvement of the 3D building block model.
Abstract: Press-hardened profiles are used e.g. for automotive
applications in order to improve light weight construction due to the
high reachable strength. The application of interior water-air spray
cooling contributes to significantly reducing the cycle time in the
production of heat-treated tubes. This paper describes a new
manufacturing method for producing press-hardened hollow profiles
by means of an additional interior cooling based on a water-air spray.
Furthermore, this paper provides the results of thorough
investigations on the properties of press-hardened tubes in
dependence of varying spray parameters.
Abstract: Evolutionary optimization methods such as genetic
algorithms have been used extensively for the construction site layout
problem. More recently, ant colony optimization algorithms, which
are evolutionary methods based on the foraging behavior of ants,
have been successfully applied to benchmark combinatorial
optimization problems. This paper proposes a formulation of the site
layout problem in terms of a sequencing problem that is suitable for
solution using an ant colony optimization algorithm.
In the construction industry, site layout is a very important
planning problem. The objective of site layout is to position
temporary facilities both geographically and at the correct time such
that the construction work can be performed satisfactorily with
minimal costs and improved safety and working environment. During
the last decade, evolutionary methods such as genetic algorithms
have been used extensively for the construction site layout problem.
This paper proposes an ant colony optimization model for
construction site layout. A simple case study for a highway project is
utilized to illustrate the application of the model.
Abstract: Rehabilitation of dam components such as foundations, buttresses, spillways and overtopping protection require a wide range of construction and design methodologies. Geotechnical Engineering considerations play an important role in the design and construction of foundations of new dams. Much investigation is required to assess and evaluate the existing dams. The application of roller compacting concrete (RCC) has been accepted as a new method for constructing new dams or rehabilitating old ones. In the past 40 years there have been so many changes in the usage of RCC and now it is one of most satisfactory solutions of water and hydropower resource throughout the world. The considerations of rehabilitation and construction of dams might differ due to upstream reservoir and its influence on penetrating and dewatering of downstream, operations requirements and plant layout. One of the advantages of RCC is its rapid placement which allows the dam to be operated quickly. Unlike ordinary concrete it is a drier mix, and stiffs enough for compacting by vibratory rollers. This paper evaluates some different aspects of RCC and focuses on its preparation progress.
Abstract: Roadway planning and design is a very complex
process involving five key phases before a project is completed;
planning, project development, final design, right-of-way, and
construction. The planning phase for a new roadway transportation
project is a very critical phase as it greatly affects all latter phases of
the project. A location study is usually performed during the
preliminary planning phase in a new roadway project. The objective
of the location study is to develop alignment alternatives that are cost
efficient considering land acquisition and construction costs. This
paper describes a methodology to develop optimal preliminary
roadway alignments utilizing spatial-data. Four optimization criteria
are taken into consideration; roadway length, land cost, land slope,
and environmental impacts. The basic concept of the methodology is
to convert the proposed project area into a grid, which represents the
search space for an optimal alignment. The aforementioned
optimization criteria are represented in each of the grid’s cells. A
spatial-data optimization technique is utilized to find the optimal
alignment in the search space based on the four optimization criteria.
Two case studies for new roadway projects in Duval County in the
State of Florida are presented to illustrate the methodology. The
optimization output alignments are compared to the proposed Florida
Department of Transportation (FDOT) alignments. The comparison is
based on right-of-way costs for the alignments. For both case studies,
the right-of-way costs for the developed optimal alignments were
found to be significantly lower than the FDOT alignments.
Abstract: Latin hypercube designs (LHDs) have been applied in
many computer experiments among the space-filling designs found in
the literature. A LHD can be randomly generated but a randomly
chosen LHD may have bad properties and thus act poorly in
estimation and prediction. There is a connection between Latin
squares and orthogonal arrays (OAs). A Latin square of order s
involves an arrangement of s symbols in s rows and s columns, such
that every symbol occurs once in each row and once in each column
and this exists for every non-negative integer s. In this paper, a
computer program was written to construct orthogonal array-based
Latin hypercube designs (OA-LHDs). Orthogonal arrays (OAs) were
constructed from Latin square of order s and the OAs constructed
were afterward used to construct the desired Latin hypercube designs
for three input variables for use in computer experiments. The LHDs
constructed have better space-filling properties and they can be used
in computer experiments that involve only three input factors.
MATLAB 2012a computer package (www.mathworks.com/) was
used for the development of the program that constructs the designs.
Abstract: The coaxial transformer-coupled push-pull circuitry
has been used widely in HF and VHF amplifiers for many decades
without significant changes in the topology of the transformers. Basic
changes over the years concerned the construction and turns ratio of
the transformers as has been imposed upon the newer technologies
active devices demands. The balun transmission line transformers
applied in push-pull amplifiers enable input/output impedance
transformation, but are mainly used to convert the balanced output
into unbalanced and the input unbalanced into balanced. A simple
and affordable alternative solution over the traditional coaxial
transformer is the coreless planar balun. A key advantage over the
traditional approach lies in the high specifications repeatability;
simplifying the amplifier construction requirements as the planar
balun constitutes an integrated part of the PCB copper layout. This
paper presents the performance analysis of a planar LDMOS
MRFE6VP5600 Push-Pull amplifier that enables robust operation in
Band III, DVB-T, DVB-T2 standards but functions equally well in
Band II, for DRM+ new generation transmitters.
Abstract: Public-private partnerships (PPP) arrangements have
been extensively used in Canada, where the participation of private
companies in financing and managing infrastructure projects has
increased significantly in the last decade, particularly in the
transportation sector. This paper analyses the evolution of the PPP
market for transportation projects in Canada and examines the
participation of Spanish developers in this market, which have been
particularly successful in winning PPP contracts during the last
decade.
Abstract: The purpose of the paper is to examine the most
critical and important factor which will affect the implementation of
Total Quality Management (TQM) in the construction industry in the
United Arab Emirates. It also examines the most effected Project
outcome from implementing TQM. A framework was also proposed
depending on the literature studies. The method used in this paper is a
quantitative study. A survey with a sample of 60 respondents was
created and distributed in a construction company in Abu Dhabi,
which includes 15 questions to examine the most critical factor that
will affect the implementation of TQM in addition to the most
effected project outcome from implementing TQM. The survey
showed that management commitment is the most important factor in
implementing TQM in a construction company. Also it showed that
Project cost is most effected outcome from the implementation of
TQM.
Management commitment is very important for implementing
TQM in any company. If the management loose interest in quality
then everyone in the organization will do so. The success of TQM
will depend mostly on the top of the pyramid. Also cost is reduced
and money is saved when the project team implement TQM. While if
no quality measures are present within the team, the project will
suffer a commercial failure.
Based on literature, more factors can be examined and added to
the model. In addition, more construction companies could be
surveyed in order to obtain more accurate results. Also this study
could be conducted outside the United Arab Emirates for further
enchantment.
Abstract: Coal fly ash is formed as a solid waste product from
the combustion of coal in coal fired power stations. Huge amounts of
fly ash are produced globally every year and are predicted to
increase. Nowadays, less than half of the fly ash is used as a raw
material for cement manufacturing, construction and the rest of it is
disposed as a waste causing yet another environmental concern. For
this reason, the recycling of this kind of slurries into useful materials
is quite important in terms of economical and environmental aspects.
The purpose of this study is to evaluate the Orhaneli and
Tuncbilek coal fly ashes for utilization in some industrial
applications. Therefore the mineralogical and chemical compositions
of these fly ashes were analyzed by X-ray fluorescence spectroscopy,
ourier-transform infrared spectrometer, and X-ray diffraction. The
silicon (Si) and aluminum (Al) in the fly ashes were activated by
alkali fusion technique with sodium hydroxide. The obtained extracts
were analyzed for Si and Al content by inductively coupled plasma
optical emission spectrometry.
Abstract: The safety and health performances aspects of a building are the most challenging aspect of facility management. It requires a deep understanding by the building managers on the factors that contribute to health and safety performances. This study attempted to develop an explanatory architectural safety performance model for stratified low-cost housing in Malaysia. The proposed Building Safety and Health Performance (BSHP) model was tested empirically through a survey on 308 construction practitioners using partial least squares (PLS) and structural equation modelling (SEM) tool. Statistical analysis results supports the conclusion that architecture, building services, external environment, management approaches and maintenance management have positive influence on safety and health performance of stratified low-cost housing in Malaysia. The findings provide valuable insights for construction industry to introduce BSHP model in the future where the model could be used as a guideline for training purposes of managers and better planning and implementation of building management.