1544881 |
Adult offspring of alcoholic parents: development and investigation of the psychometric properties of the behavior role scaleSchneider, John Donald 11 1900 (has links)
The primary objective of this study was the development and investigation of the
psychometric properties of a measurement instrument based on the integrated model of
behavior roles of offspring of alcoholic parents (Schneider, 1989,1995). The Behavior
Role Scale was developed utilizing Crocker and Algina's (1986) 10 step instrument
development process and deals directly with the concepts of the original models of
behavior roles of offspring of alcoholic parents (Black, 1981; Booz-Allen & Hamilton,
1974; Deutsch, 1983; Kritzberg, 1985; Wegscheider, 1981). The first three steps of the
instrument development were completed in an earlier investigation (Schneider, 1989). In
this investigation, steps 4 - 8 were completed.
The following activities were undertaken: step 4, the construction of an initial
pool of items; step 5, the review and revision of the items with the assistance of a panel
of experts; step 6, a preliminary tryout of the items in a pilot test; step 7, a field test of
the instrument with a nonclinical sample of offspring of alcoholic parents and offspring
of nonalcoholic parents; and, step 8, initial investigation of the psychometric properties
of the behavior role scale.
This investigation contributed the following findings. The field test yielded
reliability estimates of .72 for the Caretaker, .67 for the Super Achiever, .86 for the
Invisible One, .89 for the Jester, .78 for the Rebel, and an overall alpha of .88. Initial
validity was indicated by the emergence of a five factor model as the most interpretable
factor analysis solution. The performance of the Behavior Role Scale was also
investigated using six validity issues identified in the literature. Offspring of alcoholic
parents, offspring of nonalcoholic parents who had experienced a significant family
disruption, and offspring of nonalcoholic parents who had not experienced a significant
family disruption had significantly different scores with the Super Achiever, Invisible
One, and Rebel roles. The three groups did not demonstrate significant differences with the Caretaker or Jester roles. Additional significant differences were discovered with the
Jester and Rebel roles among offspring of alcoholic fathers when they were compared
according to their fathers' pattern of drinking.
The findings of this investigation add to the research evidence which suggests that
refinements need to be made to improve the clinical and psycho-educational uses of the
behavior roles of offspring of alcoholic parents. Recommendations for future research
include submitting the Behavior Role Scale to construct validation studies in order to
further refine its ability to measure behavior roles and to be of assistance to researchers
seeking to unravel the complexities of life for more than 28 million offspring of alcoholic
parents. / Education, Faculty of / Educational and Counselling Psychology, and Special Education (ECPS), Department of / Graduate
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1544882 |
Empirical studies in information modeling: interpretation of the object relationshipSiau, Keng Leng 11 1900 (has links)
Information modeling is the cornerstone of information systems analysis and
design. Information models not only provide the abstractions required to
facilitate communication between designers and end users, they also provide a
formal basis for tools and techniques used in developing and using
information systems. This dissertation reports on four empirical studies in
information modeling. The four studies focus on an important, yet
controversial, construct in information modeling — the relationship construct.
The theoretical foundation for the four experimental studies comprises
theories and findings from the information systems, cognitive psychology,
computer science, philosophy, and communication literature.
Because of the paucity of empirical research in the area, a two-stage research
design, consisting of the exploratory and formalized phases, is employed in this
dissertation. Two studies were conducted in the exploratory phase. The first
exploratory study investigated the effect of domain familiarity on selection of
mandatory or optional connectivity for the relationship construct by modeling
experts. The findings indicate that modeling experts tend to choose optional
over mandatory relationships, even for domains that are totally unfamiliar to
them. The second exploratory study analyzed the effect of conflicting textual
information and structural constraints on selection of mandatory or optional
connectivity by modeling experts. The results show that modeling experts tend
to focus on the information depicted by the structural constraints and ignore the textual information. This exploratory phase allowed us to explore and
develop empirical research methods and instruments for studying the
relationship construct in information modeling.
In the second phase, two formalized studies were conducted. The first
formalized study investigated the differences between modeling experts and
novices in their interpretation of information models. The results show
significant differences in the way modeling experts and novices interpret
information models. Modeling experts focus mainly on the structural
constraints and de-emphasize the textual information. Modeling novices, on
the other hand, pay more attention to the textual information than modeling
experts. The second formalized study examined the effect of different
representations of relationship on the interpretation of information models by
modeling novices. The findings indicate that the explicitness of relationship
construct and the use of verb versus noun description for relationship have a
profound impact on the accuracy of interpretation. The best combination is
one that uses an explicit relationship construct and verb for relationship
description. The worst combination is one where the relationship construct is
represented implicitly and described using noun. / Business, Sauder School of / Graduate
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1544883 |
A transient, three-dimensional, thermal model of a billet reheating furnaceScholey, Kenneth Erwin 11 1900 (has links)
Situated between the casting and rolling operations, the reheating process ensures steel
billets or slabs are at temperatures high enough (~1200°C) to enable subsequent deformation pro-cesses
to be carried out economically. Industrial reheating furnaces have varying designs, utilize
different fuel mixtures and employ top, side or bottom firing. Under steady-state operating cond-itions,
the challenge is to achieve good temperature homogenization while minimizing fuel con-sumption
and maximising furnace throughput. During furnace stoppages, which are caused by
delays in therolling mill, there is a need to minimise fuel consumption and maintain discharge
temperatures.
To gain better insight into the operation of a billet reheating furnace, a transient, three-dimen-sional
thermal model has been developed. Radiative heat transfer in three-dimensions is
solved using Hottel's "Zone Method", employing a clear-plus-three-grey gas model to represent
the furnace atmosphere. In this method, the geometrical aspects of the problem are treated sepa-rately
to produce total exchange areas that can be stored for repeated use. The main module then
calculates the energy released through combustion, the heat transferred to the steel and the move-ment
of the charge during each time step. Gas temperatures are determined from energy balances
using a Newton-Raphson iterative technique. Conduction in the billets is solved in three-dimensions
by taking into account heat transfer in the gaps between and underneath the billets. The
model further evaluates heat losses through the furnace roof, walls and hearth.
The mathematical model was verified using industrial data obtained from plant trials con-ducted
at two Canadian steel mini-mills. Results from the plant trials indicated that the billets con-tinued
to increase in temperature during furnace stoppages. The model suggests that this is due to
continuous burner firing during these stoppages even with lower firing levels. For one of the furnaces,
the model predicts the thermal efficiency to be 31% for the heating of 0.15 m (6") billets,
with 68% of the combustion energy lost in the flue gases and the remainder lost through the
refractory. Improved performance could be realized through better control of the furnace atom-sphere,
with the air/fuel ratios maintained at levels closer to stoichiometric, as well as the installa- tion of a recuperator to preheat the combustion air.
Different delay firing strategies that focussed on the recovery of the furnace were examined
with the model and it was found that the sequential return to steady-state firing reduces the
extent of billet over-heating while ensuring newly charged billets reached adequate rolling temperatures.
The model was also used to examine the effect of air/fuel ratios in each of the furnace
control zones and the benefits of recuperatively preheating the combustion air or hot-charging,
where the billets are charged into the furnace soon after casting. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate
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1544884 |
The development of a fiber-optic probe for the in vivo resonance Raman spectroscopy of neurotransmittersSchulze, Georg 11 1900 (has links)
The measurement of neurotransmitter secretions by living cells, both in living organisms
or in preparations, constitutes an enduring and vexing problem for neuroscientists due to
the large number of substances involved at very low concentrations. An ability to
correlate neurotransmitter secretions with various factors including organismic behavior
would greatly advance our understanding of the organization and functioning of central
nervous systems. This, in turn, has many important implications for the diagnosis and
treatment of disorders of central nervous systems (mainly in humans) as well as for the
design and implementation of information processing and control systems.
The work presented here was undertaken in order to explore a novel approach to this
demanding problem. The objective was to develop a probe capable of measuring
neurotransmitter secretions in real time, at physiologically relevant concentrations, and
non-invasively in situ. Data were obtained using an ultraviolet resonance Raman
spectroscopic analytical technique performed via optical fibers, and were analyzed
primarily with artificial neural networks. To this end, a prototype tunable ultraviolet
resonance Raman system was designed, assembled, comissioned and employed.
A general introduction to the problem and a discussion of existing techniques for
neurotranmitter measurement are given in Part I. In Part n, the analytical method was
shown to allow discrimination between several different neurotransmitters and some of
their precursors, both on the basis of their spectra and the selective resonance
enhancement of their spectra. Optical fibers were characterized with regard to their
suitability for use with pulsed ultraviolet radiation in Part III and on the basis thereof
selected for the construction of optical fiber probes. It was found that the performance
of optical fibers varied greatly when subjected to pulsed ultraviolet radiation, making the
selection of fibers a crucial factor in probe construction. Various design features
influencing the efficiency of optical fiber probes were investigated using both theoretical and empirical techniques. A right-angle geometry using a small diameter excitation fiber
and several larger collection fibers in close proximity produced the most efficient probe.
In Part IV the use of cell secretions as samples modelling in vivo conditions were
investigated. It was also shown that these probes could be inserted via surgically
implanted cannulae into and operated in the crania of experimental male rats without
producing discernable behavioral artifacts. In Part V some signal recovery methods were
investigated and it was shown that artificial neural networks could be used to identify
and quantify neurotransmitters based on their Raman spectra. Part VI contains an
assessment of the neuroprobe using neurotransmitter secreting cultured cells as a model
system. The thesis is concluded with a discussion of the charateristics of an ideal
biosensor, reviews the work done, and highlights some future directions.
This thesis represents my contributions toward the development of a tunable
ultraviolet resonance Raman neurotransmitter probe. Within the scope of this work,
limitations of the available equipment and other resources precluded the complete
development of a high-performance neuroprobe, however, the data presented here
demonstrate proof-of-concept and feasibility. In particular, what has hitherto been
considered impossible - the use of optical fibers for pulsed ultraviolet remote resonance
Raman spectroscopy - has been shown to be distinctly feasible. It has further been
shown that ultraviolet resonance Raman spectroscopy is well-suited to the problem of
resolving a mixture of neurotransmitters in a biological matrix. With the appropriate
state-of-the-art equipment, there is now a very real possibilty of obtaining detection
limits of lx10~9 M for the catecholamine neurotransmitters and 1x10"0" M for the
aliphatic neurotransmitters with 30 s exposure time, thus providing a novel and general
solution to the problem of neurotransmitter measurement. / Graduate and Postdoctoral Studies / Graduate
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1544885 |
Patterns of change, sources of influence : an historical study of the Canadian museum and the middle class, 1850-1950Mak, Eileen Diana 11 1900 (has links)
This thesis argues the continued relationship between museums and the middle class over
the period from 1850 to 1950, showing in particular how major events and trends affecting the
history of the middle class influenced the manner in which museums developed. It argues,
however, that, despite participation in an international bourgeois culture which included a
worldwide "museum movement', the regional circumstances of both museums and the middle
class in Canada had a significant effect on their related histories determining, if not the final
product, at least the timing of its completion and the manner in which it was reached.
This argument is made through a comparison of the histories of the Provincial Museum
of Nova Scotia, the Ontario Provincial Museum, the Royal Ontario Museum, and the British
Columbia Provincial Museum. For each institution, three themes are considered: the way in
which its collection shaped or reflected a regional identity; the form of education it offered, the
intended audience, and the ways in which both changed; and the impact of professionalization
on both the museum and the people who worked in it. The comparisons show that, despite the
uniqueness of the museums' collections and histories, in the final analysis, each institution
conformed to the patterns of the 'museum movement', or, as in the case of professionalization,
to the pattern of a professionalizing middle-class society.
Informed by recent critical work on the history of museums, this thesis uses archival and
secondary sources to establish the narratives of four Canadian museums and places them into the
broader context of the international 'museum movement', while also indicating the uniqueness
of Canadian cultural institutions created by the colonial experience. In this way, it adds a new
perspective to the history of Canadian museums. At the same time, it adds to our understanding of the Canadian middle class through its demonstration of how the major societal trends affected
individual members of that class. / Arts, Faculty of / History, Department of / Graduate
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1544886 |
Liquefaction of sands under multi-axial loadingUthayakumar, Muthukumarasamy 11 1900 (has links)
A fundamental study of the undrained behaviour of sands under multi-axial loading is
presented. The study was performed by using the hollow cylinder torsional (HCT) device. The
HCT is the only device that permits a soil specimen to be subjected to multi-axial loading with
controlled variations in the magnitudes of the three principal stresses and the direction of the
major principal stress with the vertical deposition direction.
The main objective of the study was to assess the effects of principal stress magnitude,
directions and their rotation on sand liquefaction. This is achieved by a systematic study of static
and cyclic undrained behaviour of reconstituted loose sand. Shear loading is carried out under
strain control. Only such loading permits the needed capture of post peak strain softening
characteristics of loose sands. Undesirable runaway strains are inevitable in stress controlled
loading modes.
In addition to the investigations in the hollow cylinder torsional device, sand behaviour in
simple shear as well as under the triaxial conditions was also assessed as reference for
comparisons with that under multi-axial stresses. The investigations were carried out using two
sands - Fraser River sand and Syncrude sand. Sand specimens were reconstituted by water
pluviation, which is considered to duplicate the fabric ofin-situ fluvial and hydraulic fill deposits.
Independence of the effective stress path and stress-strain characteristics from the total
stress path under fixed principal stress directions and constant value of intermediate principal
stress parameter is illustrated. The undrained response of loose sand is highly dependent on the
loading direction, implying inherent anisotropy. The friction angle mobilized at phase
transformation or steady state is a unique material property, independent of the mode of loading static or cyclic, direction of principal stresses, intermediate principal stress level, consolidation
history and the stress and void ratio state prior to undrained shear. There is no unique
relationship between steady state or phase transformation strength and void ratio that is
independent of the stress path, implying that a unique steady state line does not exist for a sand.
The influence of intermediate principal stress, on undrained response is small when the
intermediate principal stress parameter, that reflects value of this stress relative to the major and
the minor values, is less than about 0.5. At constant values of other parameters increasing
confining stress and decreasing relative density under multi-axial loading promote a higher degree
of contractive response.
The history of principal stress directions during principal stress rotation does not seem to
have any appreciable effect on the peak and steady state or phase transformation strength. These
strengths are apparently controlled by the peak value of major principal stress inclination
experienced during shearing with respect to vertical direction.
Principal stresses undergo continuous rotation from 0 to about ±45° in simple shear
deformation. A simultaneous change in intermediate principal stress occurs as the major principal
stress rotates. The maximum shear stress and maximum shear strain in conventional simple shear
deformation approximately equals the horizontal shear stress and shear strain respectively.
For a given initial stress and void ratio state, the number of cycles to liquefaction is
smaller under cyclic triaxial than under similar 90° jump rotation that do not invoke the weakest
triaxial extension loading mode during shear. For a given direction of principal stresses, if the
sand is contractive under static loading, it would also be contractive under cyclic loading, provided that the cyclic deviator stress amplitude is higher than the steady state or phase
transformation strength in static loading. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
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1544887 |
Informal settlement upgrading in Durban, South Africa : building institutional capacity to sustain the improvement processVan Horen, Basil 11 1900 (has links)
This research examines the planning of the Besters Camp informal settlement in-situ upgrading
project in Durban, South Africa. International experience indicates that in-situ upgrading has
generally been successful in delivering services to the urban poor. It also confirms, however, that
benefits of upgrading are mostly confined to project localities, and that the institutional capacity
necessary for ongoing improvement in the lives of settlement residents is seldom created.
Drawing from experience as a planner in some of South Africa's first generation of settlement
upgrading projects, this research focuses on the question of how informal settlement upgrading
can be planned in order to contribute to the continuity of the settlement improvement process.
An important implication of the 'informalization' process in many Third World cities is that parts
of cities in which the de facto rules of the game are dominant are growing considerably more
rapidly than the 'formal city', which is governed according to the de jure instruments of control,
such as statutory law, planning regulation, and legal administrative authority. In this context, the
most common approach to planning the upgrading of shack settlements is to attempt to legalize, or
'formalize the informal'.
Experience in Besters Camp upgrade elucidates ways of moving beyond a narrow focus on
legalization, and onto more flexible regularization strategies. These strategies attempt to bridge
the gap between de jure and de facto systems by integrating elements of both into the planning
process, and thereby contributing to an amended legal regulatory framework appropriate to
planning in informal settlements. Regularization involves putting in place the institutions - that is,
the norms and structures - that are economically and politically viable, and which have the
potential to carry the consolidation process forward into the longer term. Regularization takes as
its starting point the delivery of services, which provides an activity into which capacity building
initiatives can be integrated. Importantly, in order to sustain the impacts of upgrading projects, it
is necessary to connect local settlement-level institutions and metropolitan-level institutions in
such a way as to provide a relationship of complementary autonomy at both levels. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
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1544888 |
An approach to the management of groundwater pollutionWalker, Daniel Arthur 11 1900 (has links)
This thesis considers the management of groundwater pollution as a societal and technical problem. It consists
of four elements: theoretical foundation, conceptual model, management strategies, and compound model.
The theoretical foundation recognizes two distinct approaches to management: the hard and soft paradigms.
The hard paradigm deals with hard problems, characterized by well-defined boundaries, goals, and alternatives;
quantifiable uncertainty; and a unilateral decision-maker. A hard problem can be addressed with algorithmic logic
and linear procedure. The hard paradigm employs condensed conceptual models, and relies on transform models as
predictive tools. (A conceptual model synthesizes observations; a transform model maps an input to an output.) The
soft paradigm deals with soft problems, characterized by ambiguous boundaries, goals, and alternatives; nonquantifiable
uncertainty; and multiple decision-makers. A soft problem requires argumentation and iterative
procedure. The soft paradigm relies on detailed conceptual models, and employs transform models as heuristic
tools.
The two paradigms can be reconciled through the concept of soft/hard complementarity which views a
problem as a soft problem in the overall sense, with embedded hard sub-problems.
The conceptual model contains two major systems: the pollution system, consisting of groundwater flow and
pollutant transport subsystems; and the management system, consisting of technical and decision subsystems. The
emphasis is on the decision subsystem, which is described in terms of rules of governance; multiple issues; multiple
stakeholders; and various decision processes.
The management strategies include both decision and technical strategies. The decision strategies consist of
three subsets: strategies for iterative decision-making; strategies for integration of the decision system; and
strategies for emphasizing negotiation. The technical strategies deal with iterative technique; integration of the
technical system; and design for mitigation.
The compound model is called SAM (Simulated Aquifer Management). It consists of a set of transform
models, joined by linkages which are either algorithmic or which require the modeler's subjective judgement. The
technical system is represented by models of flow, transport, optimization of pumping rates, and costing of technical
options. The decision system is represented a game theory model and a role-playing exercise. SAM is used as a
heuristic device, and as illustration of both the management strategies and soft/hard complementarity. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
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1544889 |
Bubble columns and three-phase fluidized beds : flow regimes and bubble characteristicsZhang, Junping 11 1900 (has links)
Experiments were carried out in three-phase fluidized beds containing solid particles
contacted by upward co-current flow of air and water, to study flow patterns of gas-liquid-solid
systems.
The minimum fluidization velocity and the particle transport velocity in a gas-hquid-solid
mixture delineate the boundaries between three types of flow systems — fixed bed, fluidized bed
and transport flow. Both of these transition velocities were measured for a variety of particles. A
theoretical model, the Gas-Perturbed Liquid Model, was developed to predict the minimum liquid
fluidization velocity of a bed of solid particles in the presence of a fixed co-current superficial gas
velocity. This model, together with an appropriate equation for the gas holdup on a solids-free
basis, shows almost as good agreement with the present experimental data and those from the
literature as the best available empirical equation for the minimum hquid fluidization velocity at
low to intermediate superficial gas velocity, and has the advantage of correctly reducing to the
Wen-Yu equation for minimum two-phase fluidization as the superficial gas velocity goes to zero.
Two types of particle movement were observed as the superficial liquid velocity approaches the
particle transport velocity. For 1.2 mm steel shot, clusters of particles were found in both liquidsolid
and gas-hquid-solid systems. For 1.5 and 4.5 mm glass beads, on the other hand, no particle
clusters were observed. In the latter case, a mathematical model the Particle Transport Velocity
Model, was developed to predict the superficial hquid velocity for particle transport in upward
gas-hquid flow. An empirical correlation was also proposed for the transition from fluidized bed
to particle transport flow. Both predictions showed good agreement with experimental data
obtained in the present work and in the literature for a wide range of superficial gas velocities.
Within the fluidized bed, based on bubble characteristics, dispersed bubble flow, discrete
bubble flow, coalesced bubble flow, slug flow, churn flow, bridging flow and annular flow regimes were identified and characterized, at different combinations of gas and liquid superficial velocities.
These flow regimes were also observed for two-phase air-water systems.
A comprehensive measurement method using a conductivity probe was developed to
determine flow regime transitions based on bubble frequency, Sauter mean bubble chord length
and the time taken by a bubble to pass a given point. Criteria for determining flow regime
transitions were developed in an air-water two-phase system and then successfully applied to gasliquid-
solid three-phase fluidized beds. Flow regime maps were derived based on experimental
data for three different three-phase systems. As in two-phase gas-liquid systems, chum flow,
bridging flow and annular flow can be observed at high gas velocities in three-phase fluidized
beds. Empirical correlations were developed to predict the flow regime boundaries in the three phase
fluidized systems investigated. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
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1544890 |
Resistance of concrete railroad ties to impact loadingWang, Nianzhi 11 1900 (has links)
In some sections of railroad, many prestressed concrete railway ties were found to
be cracked after being in service for only a few months, because of impact loading. The
dynamic properties of concrete ties were thus studied in this work. Two typical types of
impulse encountered in track, due to rail abnormalities and "wheel flats" of trains, were
successfully simulated by the use of a 578 kg impact machine and a 60 kg drop weight
impact machine, respectively. The previously developed "single-blow" impact technique
has been extended into a "multi-blow" impact technique, in order to better simulate the
repeated impact loading on the concrete tie in track.
It was found that the stiffness of the rubber support played an important role in the
dynamic response of the ties. Using the soft rubber support caused a low maximum load,
low loading rate, a higher fracture energy and a ductile flexural fracture mode. Using the
hard support caused a brittle flexure-shear or shear failure mode. Crack mode analysis
showed that the cause of the crack mode changing from flexural under quasi-static loading
to shear under impact loading is that the shear to moment ratio at the mid-span of the tie
changes under impact. A crack mode prediction method was proposed.
In the second series of tests, twelve types of modified ties were tested. The effects
of the concrete strength, steel fibre additions, changes in prestressing force, the presence
of stirrups were examined. The crack opening length and residual crack length were
detected by crack detection gauges. Steel fibres greatly improved tie behaviour, leading to
shorter and finer cracks in the concrete. Stirrups can, particularly when used in
conjunction with fibres, effectively retard the deterioration of the concrete tie. The ties
with a 40 MPa compressive strength and 30 mm fibres behaved very well. They were
markedly better than the ties which had the same fibre content but a 65 MPa concrete
compressive strength. The reason for this is that reducing the concrete compressive strength or prestressing level of the tie resulted in a reduction of the dynamic flexural
stiffness and hence the magnitude of the impact loads. It is believed that if these measures
were combined with the use of steel fibres in the concrete, a new type of concrete tie, with
improved ductility and high resistance to impact load could be developed.
Dynamic analysis of the ties showed that a different impulse duration or frequency
may lead to a very different concrete strain response. This may need to be considered in
the wheel truing program in service.
Thirteen types of commercial pads were tested and ranked. Soft pads may act as a
low-pass filter, leading to lower amplitudes of the concrete strain vibration. However, it
may structurally deteriorate more quickly, leading to an even worse influence on the ties
after a period of time in service. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
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