Abstract: Proof of controlling crack width is a basic condition
for securing suitable performance in serviceability limit state. The
cracking in concrete can occur at any time from the casting of time to
the years after the concrete has been set in place. Most codes struggle
with offering procedure for crack width calculation. There is lack in
availability of design charts for designers to compute crack width
with ease. The focus of the study is to utilize design charts and
parametric equations in calculating crack width with minimum error.
The paper contains a simplified procedure to calculate crack width
for reinforced concrete (RC) sections subjected to bending with axial
tensile force following the guidelines of Euro code [DS EN-1992-1-1
& DS EN-1992-1-2]. Numerical examples demonstrate the
application of the suggested procedure. Comparison with parallel
analytical tools supports the validity of result and show the
percentage deviation of crack width in both the procedures. The
technique is simple, user friendly and ready to evolve for a greater
spectrum of section sizes and materials.
Abstract: Systems Engineering plays a key role during industrial
product development of complex technical systems. The need for
systems engineers in industry is growing. But there is a gap between
the industrial need and the academic education. Normally the
academic education is focused on the domain specific design,
implementation and testing of technical systems. Necessary systems
engineering expertise like knowledge about requirements analysis,
product cost estimation, management or social skills are poorly
taught. Thus there is the need of new academic concepts for teaching
systems engineering skills. This paper presents a project-orientated
training concept to prepare students from different technical degree
programs for systems engineering activities. The training concept has
been initially implemented and applied in the industrial engineering
master program of the University of Applied Sciences Offenburg.
Abstract: Cavitation in cryogenic liquids is widely present in
contemporary science. In the current study, we re-examine a
previously validated acoustic cavitation model which was developed
for a gas bubble in liquid water. Furthermore, simulations of
cryogenic fluids including the thermal effect, the effect of acoustic
pressure amplitude and the frequency of sound field on the bubble
dynamics are presented. A gas bubble (Helium) in liquids Nitrogen,
Oxygen and Hydrogen in an acoustic field at ambient pressure and
low temperature is investigated numerically. The results reveal that
the oscillation of the bubble in liquid Hydrogen fluctuates more than
in liquids Oxygen and Nitrogen. The oscillation of the bubble in
liquids Oxygen and Nitrogen is approximately similar.
Abstract: Laplace transformations have wide applications in
engineering and sciences. All previous studies of modified Laplace
transformations depend on differential equation with initial
conditions. The purpose of our paper is to solve the linear differential
equations (not initial value problem) and then find the general
solution (not particular) via the Laplace transformations without
needed any initial condition. The study involves both types of
differential equations, ordinary and partial.
Abstract: The final step to complete the “Analytical Systems
Engineering Process” is the “Allocated Architecture” in which all
Functional Requirements (FRs) of an engineering system must be
allocated into their corresponding Physical Components (PCs). At
this step, any design for developing the system’s allocated
architecture in which no clear pattern of assigning the exclusive
“responsibility” of each PC for fulfilling the allocated FR(s) can be
found is considered a poor design that may cause difficulties in
determining the specific PC(s) which has (have) failed to satisfy a
given FR successfully. The present study utilizes the Axiomatic
Design method principles to mathematically address this problem and
establishes an “Axiomatic Model” as a solution for reaching good
alternatives for developing the allocated architecture. This study
proposes a “loss Function”, as a quantitative criterion to monetarily
compare non-ideal designs for developing the allocated architecture
and choose the one which imposes relatively lower cost to the
system’s stakeholders. For the case-study, we use the existing design
of U. S. electricity marketing subsystem, based on data provided by
the U.S. Energy Information Administration (EIA). The result for
2012 shows the symptoms of a poor design and ineffectiveness due to
coupling among the FRs of this subsystem.
Abstract: Self-compacting concrete (SCC) developed in Japan
in the late 80s has enabled the construction industry to reduce
demand on the resources, improve the work condition and also
reduce the impact of environment by elimination of the need for
compaction. Fuzzy logic (FL) approaches has recently been used to
model some of the human activities in many areas of civil
engineering applications. Especially from these systems in the model
experimental studies, very good results have been obtained. In the
present study, a model for predicting compressive strength of SCC
containing various proportions of fly ash, as partial replacement of
cement has been developed by using Fuzzy Inference System (FIS).
For the purpose of building this model, a database of experimental
data were gathered from the literature and used for training and
testing the model. The used data as the inputs of fuzzy logic models
are arranged in a format of five parameters that cover the total binder
content, fly ash replacement percentage, water content,
superplasticizer and age of specimens. The training and testing results
in the fuzzy logic model have shown a strong potential for predicting
the compressive strength of SCC containing fly ash in the considered
range.
Abstract: Machining parameters are very important in
determining the surface quality of any material. In the past decade,
some new engineering materials were developed for the
manufacturing industry which created a need to conduct an
investigation on the impact of the said parameters on their surface
roughness. Polyurethane (PU) block is widely used in the automotive
industry to manufacture parts such as checking fixtures that are used
to verify the dimensional accuracy of automotive parts. In this paper,
the design of experiment (DOE) was used to investigate on the effect
of the milling parameters on the PU block. Furthermore, an analysis
of the machined surface chemical composition was done using
scanning electron microscope (SEM). It was found that the surface
roughness of the PU block is severely affected when PU undergoes a
flood machining process instead of a dry condition. In addition the
stepover and the silicon content were found to be the most significant
parameters that influence the surface quality of the PU block.
Abstract: The effect of a 3-dimensional (3D) blade on the turbine
characteristics of Wells turbine for wave energy conversion has been
investigated experimentally by model testing under steady flow
conditions in this study, in order to improve the peak efficiency and
stall characteristics. The aim of use of 3D blade is to prevent flow
separation on the suction surface near the tip. The chord length is
constant with radius and the blade profile changes gradually from the
mean radius to tip. The proposed blade profiles in the study are
NACA0015 from the hub to mean radius and NACA0025 at the tip.
The performances of Wells turbine with 3D blades has been compared
with those of the original Wells turbine, i.e., the turbine with
2-dimensional (2D) blades. As a result, it was concluded that although
the peak efficiency of Wells turbine can be improved by the use of the
proposed 3D blade, its blade does not overcome the weakness of
stalling.
Abstract: Excavation and retaining walls are of challenging
issues in civil engineering. In this study, the behavior of one
important type of supporting systems called Contiguous Bored Pile
(CBP) retaining wall is investigated using a physical model. Besides,
a comparison is made between two modes of free end piles (soft bed)
and fixed end piles (stiff bed). Also a back calculation of effective
length (the real free length of pile) is done by measuring lateral
deflection of piles in different stages of excavation in both
aforementioned cases. Based on observed results, for the fixed end
mode, the effective length to free length ratio (Leff/L0) is equal to
unity in initial stages of excavation and less than 1 in its final stages
in a decreasing manner. While this ratio for free end mode, remains
constant during all stages of excavation and is always less than unity.
Abstract: Communicating and managing customers’
requirements in software development projects play a vital role in the
software development process. While it is difficult to do so locally, it
is even more difficult to communicate these requirements over
distributed boundaries and to convey them to multiple distribution
customers. This paper discusses the communication of multiple
distribution customers’ requirements in the context of customised
software products. The main purpose is to understand the challenges
of communicating and managing customisation requirements across
distributed boundaries. We propose a model for Communicating
Customisation Requirements of Multi-Clients in a Distributed
Domain (CCRD). Thereafter, we evaluate that model by presenting
the findings of a case study conducted with a company with
customisation projects for 18 distributed customers. Then, we
compare the outputs of the real case process and the outputs of the
CCRD model using simulation methods. Our conjecture is that the
CCRD model can reduce the challenge of communication
requirements over distributed organisational boundaries, and the
delay in decision making and in the entire customisation process
time.
Abstract: Corrosion inhibitors are widely used in concrete
industry to reduce the corrosion rate of steel rebar which is present in
contact with aggressive environments. The present work aims to
using Zamzam water from well located within the Masjid al-Haram
in Mecca, Saudi Arabia 20 m (66 ft) east of the Kaaba, the holiest
place in Islam as corrosion inhibitor for steel in rain water and
simulated acid rain. The effect of Zamzam water was investigated by
electrochemical impedance spectroscopy (EIS) and Potentiodynamic
polarization techniques in Department of Civil Engineering - IUT
Saint-Nazaire, Nantes University, France. Zamzam water is
considered to be one of the most important steel corrosion inhibitor
which is frequently used in different industrial applications. Results
showed that zamzam water gave a very good inhibition for steel
corrosion in rain water and simulated acid rain.
Abstract: Ontologies provide a common understanding of a
specific domain of interest that can be communicated between people
and used as background knowledge for automated reasoning in a
wide range of applications. In this paper, we address the design of
multilingual ontologies following well-defined knowledge
engineering methodologies with the support of novel collaborative
development approaches. In particular, we present a collaborative
platform which allows ontologies to be developed incrementally in
multiple languages. This is made possible via an appropriate mapping
between language independent concepts and one lexicalization per
language (or a lexical gap in case such lexicalization does not exist).
The collaborative platform has been designed to support the
development of the Universal Knowledge Core, a multilingual
ontology currently in English, Italian, Chinese, Mongolian, Hindi and
Bangladeshi. Its design follows a workflow-based development
methodology that models resources as a set of collaborative objects
and assigns customizable workflows to build and maintain each
collaborative object in a community driven manner, with extensive
support of modern web 2.0 social and collaborative features.
Abstract: Regardless of the manufacturing process used,
subtractive or additive, material, purpose and application, produced
components are conventionally solid mass with more or less complex
shape depending on the production technology selected. Aspects
such as reducing the weight of components, associated with the low
volume of material required and the almost non-existent material
waste, speed and flexibility of production and, primarily, a high
mechanical strength combined with high structural performance, are
competitive advantages in any industrial sector, from automotive,
molds, aviation, aerospace, construction, pharmaceuticals, medicine
and more recently in human tissue engineering. Such features,
properties and functionalities are attained in metal components
produced using the additive technique of Rapid Prototyping from
metal powders commonly known as Selective Laser Melting (SLM),
with optimized internal topologies and varying densities. In order to
produce components with high strength and high structural and
functional performance, regardless of the type of application, three
different internal topologies were developed and analyzed using
numerical computational tools. The developed topologies were
numerically submitted to mechanical compression and four point
bending testing. Finite Element Analysis results demonstrate how
different internal topologies can contribute to improve mechanical
properties, even with a high degree of porosity relatively to fully
dense components. Results are very promising not only from the
point of view of mechanical resistance, but especially through the
achievement of considerable variation in density without loss of
structural and functional high performance.
Abstract: A key issue in seismic risk analysis within the context
of Performance-Based Earthquake Engineering is the evaluation of
the expected seismic damage of structures under a specific
earthquake ground motion. The assessment of the seismic
performance strongly depends on the choice of the seismic Intensity
Measure (IM), which quantifies the characteristics of a ground
motion that are important to the nonlinear structural response. Several
conventional IMs of ground motion have been used to estimate their
damage potential to structures. Yet, none of them has been proved to
be able to predict adequately the seismic damage. Therefore,
alternative, scalar intensity measures, which take into account not
only ground motion characteristics but also structural information
have been proposed. Some of these IMs are based on integration of
spectral values over a range of periods, in an attempt to account for
the information that the shape of the acceleration, velocity or
displacement spectrum provides. The adequacy of a number of these
IMs in predicting the structural damage of 3D R/C buildings is
investigated in the present paper. The investigated IMs, some of
which are structure specific and some are non structure-specific, are
defined via integration of spectral values. To achieve this purpose
three symmetric in plan R/C buildings are studied. The buildings are
subjected to 59 bidirectional earthquake ground motions. The two
horizontal accelerograms of each ground motion are applied along
the structural axes. The response is determined by nonlinear time
history analysis. The structural damage is expressed in terms of the
maximum interstory drift as well as the overall structural damage
index. The values of the aforementioned seismic damage measures
are correlated with seven scalar ground motion IMs. The comparative
assessment of the results revealed that the structure-specific IMs
present higher correlation with the seismic damage of the three
buildings. However, the adequacy of the IMs for estimation of the
structural damage depends on the response parameter adopted.
Furthermore, it was confirmed that the widely used spectral
acceleration at the fundamental period of the structure is a good
indicator of the expected earthquake damage level.
Abstract: According to the demand of the power and
refrigeration industry, the theoretical and practical teachings of the
Thermal Energy and Power Engineering characteristic specialty in
china are studied. The teaching reform and practice of the Thermal
Energy and Power Engineering specialty have been carried out,
including construction and reform measures, teaching reform and
practice, features, and achievements. Proved by practices, the
theoretical and practical teaching effects are obvious. The study results
can provides certain reference experience for theoretical and practical
teachings of the related specialties in china.
Abstract: It is usually difficult for students to understand some
basic theories in learning thermal energy and power engineering
course. A new teaching method was proposed that we should introduce
the comparison research method of those theories to help them being
understood. “Homogeneous and heterogeneous catalysis” teaching is
analyzed as an example by comparison research method.
Abstract: Many problems in science and engineering field require
the solution of shifted linear systems with multiple right hand
sides and multiple shifts. To solve such systems efficiently, the
implicitly restarted global GMRES algorithm is extended in this
paper. However, the shift invariant property could no longer hold over
the augmented global Krylov subspace due to adding the harmonic
Ritz matrices. To remedy this situation, we enforce the collinearity
condition on the shifted system and propose shift implicitly restarted
global GMRES. The new method not only improves the convergence
but also has a potential to simultaneously compute approximate
solution for the shifted systems using only as many matrix vector
multiplications as the solution of the seed system requires. In
addition, some numerical experiments also confirm the effectiveness
of our method.
Abstract: Applied industrial engineering is concerned with
imparting employable skills to improve the productivity for current
situation of products and services. The purpose of this case study is to
present the results of an initial research study conducted to identify
the desired professional characteristics of an industrial engineer with
an undergraduate degree and the emerging topic areas that should be
incorporated into the curriculum to prepare industrial engineering
(IE) graduates for the future workforce. Conclusions and
recommendations for applied industrial engineering syllabus have
been gathered and reported below. A two-pronged approach was
taken which included a method of benchmarking by comparing the
applied industrial engineering curricula of various universities and an
industry survey to identify job market requirements. This
methodology produced an analysis of the changing nature of
industrial engineering from learning to practical education. A
curriculum study for engineering is a relatively unexplored area of
research in the Middle East, much less for applied industrial
engineering. This work is an effort to bridge the gap between
theoretical study in the classroom and the real world work
applications in the industrial and service sectors.
Abstract: Many studies have revealed the fact of the complexity
of ontology building process. Therefore there is a need for a new
approach which one of that addresses the socio-technical aspects in the
collaboration to reach a consensus. Meta-design approach is
considered applicable as a method in the methodological model of
socio-technical ontology engineering. Principles in the meta-design
framework are applied in the construction phases of the ontology. A
web portal is developed to support the meta-design principles
requirements. To validate the methodological model semantic web
applications were developed and integrated in the portal and also used
as a way to show the usefulness of the ontology. The knowledge based
system will be filled with data of Indonesian medicinal plants. By
showing the usefulness of the developed ontology in a semantic web
application, we motivate all stakeholders to participate in the
development of knowledge based system of medicinal plants in
Indonesia.
Abstract: In a highly competitive environment, it becomes more
important to shorten the whole business process while delivering or
even enhancing the business value to the customers and suppliers.
Although the workflow management systems receive much attention
for its capacity to practically support the business process enactment,
the effective workflow modeling method remain still challenging and
the high degree of process complexity makes it more difficult to gain
the short lead time. This paper presents a workflow structuring method
in a holistic way that can reduce the process complexity using
activity-needs and formal concept analysis, which eventually enhances
the key performance such as quality, delivery, and cost in business
process.