Abstract: Following the loss of NASA's Space Shuttle
Columbia in 2003, it was determined that problems in the agency's
organization created an environment that led to the accident. One
component of the proposed solution resulted in the formation of the
NASA Engineering Network (NEN), a suite of information retrieval
and knowledge-sharing tools. This paper describes the
implementation of communities of practice, which are formed along
engineering disciplines. Communities of practice enable engineers to
leverage their knowledge and best practices to collaborate and take
information learning back to their jobs and embed it into the
procedures of the agency. This case study offers insight into using
traditional engineering disciplines for virtual collaboration, including
lessons learned during the creation and establishment of NASA-s
communities.
Abstract: This study demonstrates the use of Class F fly ash in
combination with lime or lime kiln dust in the full depth reclamation
(FDR) of asphalt pavements. FDR, in the context of this paper, is a
process of pulverizing a predetermined amount of flexible pavement
that is structurally deficient, blending it with chemical additives and
water, and compacting it in place to construct a new stabilized base
course. Test sections of two structurally deficient asphalt pavements
were reclaimed using Class F fly ash in combination with lime and
lime kiln dust. In addition, control sections were constructed using
cement, cement and emulsion, lime kiln dust and emulsion, and mill
and fill. The service performance and structural behavior of the FDR
pavement test sections were monitored to determine how the fly ash
sections compared to other more traditional pavement rehabilitation
techniques. Service performance and structural behavior were
determined with the use of sensors embedded in the road and Falling
Weight Deflectometer (FWD) tests. Monitoring results of the FWD
tests conducted up to 2 years after reclamation show that the cement,
fly ash+LKD, and fly ash+lime sections exhibited two year resilient
modulus values comparable to open graded cement stabilized
aggregates (more than 750 ksi). The cement treatment resulted in a
significant increase in resilient modulus within 3 weeks of
construction and beyond this curing time, the stiffness increase was
slow. On the other hand, the fly ash+LKD and fly ash+lime test
sections indicated slower shorter-term increase in stiffness. The fly
ash+LKD and fly ash+lime section average resilient modulus values
at two years after construction were in excess of 800 ksi. Additional
longer-term testing data will be available from ongoing pavement
performance and environmental condition data collection at the two
pavement sites.
Abstract: Experimental data are presented to show the influence of different types of chemical demulsifier on the stability and demulsification of emulsions. Three groups of demulsifier with different functional groups were used in this work namely amines, alcohol and polyhydric alcohol. The results obtained in this study have exposed the capability of chemical breaking agents in destabilization of water in crude oil emulsions. From the present study, found that molecular weight of the demulsifier were influent the capability of the emulsion to separate.
Abstract: Pakistani doctors (MBBS) are emigrating towards developed countries for professional adjustments. This study aims to highlight causes and consequences of doctors- brain drain from Pakistan. Primary data was collected from Mayo Hospital, Lahore by interviewing doctors (n=100) through systematic random sampling technique. It found that various socio-economic and political conditions are working as push and pull factors for brain drain of doctors in Pakistan. Majority of doctors (83%) declared poor remunerations and professional infrastructure of health department as push factor of doctors- brain drain. 81% claimed that continuous instability in political situation and threats of terrorism are responsible for emigration of doctors. 84% respondents considered fewer opportunities of further studies responsible for their emigration. Brain drain of doctors is affecting health sector-s policies / programs, standard doctor-patient ratios and quality of health services badly.
Abstract: The topic of surface flattening plays a vital role in the field of computer aided design and manufacture. Surface flattening enables the production of 2D patterns and it can be used in design and manufacturing for developing a 3D surface to a 2D platform, especially in fashion design. This study describes surface flattening based on minimum energy methods according to the property of different fabrics. Firstly, through the geometric feature of a 3D surface, the less transformed area can be flattened on a 2D platform by geodesic. Then, strain energy that has accumulated in mesh can be stably released by an approximate implicit method and revised error function. In some cases, cutting mesh to further release the energy is a common way to fix the situation and enhance the accuracy of the surface flattening, and this makes the obtained 2D pattern naturally generate significant cracks. When this methodology is applied to a 3D mannequin constructed with feature lines, it enhances the level of computer-aided fashion design. Besides, when different fabrics are applied to fashion design, it is necessary to revise the shape of a 2D pattern according to the properties of the fabric. With this model, the outline of 2D patterns can be revised by distributing the strain energy with different results according to different fabric properties. Finally, this research uses some common design cases to illustrate and verify the feasibility of this methodology.
Abstract: In this investigation, types of commercial and special
polyacrylonitrile (PAN) fibers contain sodium 2-methyl-2-
acrylamidopropane sulfonate (SAMPS) and itaconic acid (IA)
comonomers were studied by fourier transform infrared (FT-IR)
spectroscopy. The study of FT-IR spectra of PAN fibers samples
with different comonomers shows that during stabilization of PAN
fibers, the peaks related to C≡N bonds and CH2 are reduced sharply.
These reductions are related to cyclization of nitrile groups and
stabilization procedure. This reduction in PAN fibers contain IA
comonomer is very intense in comparison with PAN fibers contain
SAMPS comonomer. This fact indicates the cycling and stabilization
for sample contain IA comonomer have been conducted more
completely. Therefore the carbon fibers produced from this material
have higher tensile strength due to suitable stabilization.
Abstract: This paper presents the buckling analysis of short and
long functionally graded cylindrical shells under thermal and
mechanical loads. The shell properties are assumed to vary
continuously from the inner surface to the outer surface of the shell.
The equilibrium and stability equations are derived using the total
potential energy equations, Euler equations and first order shear
deformation theory assumptions. The resulting equations are solved
for simply supported boundary conditions. The critical temperature
and pressure loads are calculated for both short and long cylindrical
shells. Comparison studies show the effects of functionally graded
index, loading type and shell geometry on critical buckling loads of
short and long functionally graded cylindrical shells.
Abstract: This paper deals with the conceptual design of the
new aeroelastic demonstrator for the whirl flutter simulation. The
paper gives a theoretical background of the whirl flutter phenomenon
and describes the events of the whirl flutter occurrence in the
aerospace practice. The second part is focused on the experimental
research of the whirl flutter on aeroelastic similar models. Finally the
concept of the new aeroelastic demonstrator is described. The
demonstrator represents the wing and engine of the twin turboprop
commuter aircraft including a driven propeller. It allows the changes
of the main structural parameters influencing the whirl flutter
stability characteristics. It is intended for the experimental
investigation of the whirl flutter in the wind tunnel. The results will
be utilized for validation of analytical methods and software tools.
Abstract: This research sought to discover the forms of
promotion and dissemination of traditional local wisdom that are
used to create occupations among the elderly at Noanmueng
Community, Muang Sub-District, Baan Doong District, Udornthani
Province. The criteria used to select the research sample group were:
having a role involved in the promotion and dissemination of
traditional local wisdom to create occupations among the elderly;
being an experienced person who the residents of Noanmueng
Community find trustworthy; and having lived in Noanmueng
Community for a long time so as to be able to see the development
and change that occurs. A total of 16 persons were thus selected. Data
was gathered through a qualitative study, using semi-structured indepth
interviews. The collected data was then summarized and
discussed according to the research objectives. Finally, the data was
presented in narrative format. Results found that the identifying
traditional local wisdom of the community (which grew from the
residents’ experience and beneficial usage in daily life, passed down
from generation to generation) was the weaving of cloth and
basketry. As for the manner of promotion and dissemination of
traditional local wisdom, these skills were passed down through
teaching by example to family members, relatives and others in the
community. This was largely the initiative of the elders or elderly
members of the community. In order for the promotion and
dissemination of traditional local wisdom to create occupations
among the elderly, the traditional local wisdom should be supported
in every way through participation of the community members. For
example, establish a museum of traditional local wisdom for the
collection of traditional local wisdom in various fields, both from the
past and present innovations. This would be a source of pride for the
community, simultaneously helping traditional local wisdom to
become widely known and to create income for the community’s
elderly. Additional ways include organizing exhibitions of products
made by traditional local wisdom, finding both domestic and
international markets, as well as building both domestic and
international networks aiming to find opportunities to market
products made by traditional local wisdom.
Abstract: Studies in neuroscience suggest that both global and
local feature information are crucial for perception and recognition of
faces. It is widely believed that local feature is less sensitive to
variations caused by illumination, expression and illumination. In
this paper, we target at designing and learning local features for face
recognition. We designed three types of local features. They are
semi-global feature, local patch feature and tangent shape feature.
The designing of semi-global feature aims at taking advantage of
global-like feature and meanwhile avoiding suppressing AdaBoost
algorithm in boosting weak classifies established from small local
patches. The designing of local patch feature targets at automatically
selecting discriminative features, and is thus different with traditional
ways, in which local patches are usually selected manually to cover
the salient facial components. Also, shape feature is considered in
this paper for frontal view face recognition. These features are
selected and combined under the framework of boosting algorithm
and cascade structure. The experimental results demonstrate that the
proposed approach outperforms the standard eigenface method and
Bayesian method. Moreover, the selected local features and
observations in the experiments are enlightening to researches in
local feature design in face recognition.
Abstract: Centrally controlled authentication and authorization services can provide enterprise with an increase in security, more flexible access control solutions and an increased users' trust. By using redirections, users of all Web-based applications within an organization are authenticated at a single well known and secure Web site and using secure communication protocol. Users are first authenticated at the central server using their domain wide credentials before being redirected to a particular Web-based application. The central authentication server will then provide others with pertinence authorization related particulars and credentials of the authenticated user to the specific application. The trust between the clients and the server hosts is established by secure session keys exchange. Case- studies are provided to demonstrate the usefulness and flexibility of the proposed solution.
Abstract: The two-stage compensator designs of linear system are
investigated in the framework of the factorization approach. First, we
give “full feedback" two-stage compensator design. Based on this
result, various types of the two-stage compensator designs with partial
feedbacks are derived.
Abstract: This paper studies questions of continuous data dependence and uniqueness for solutions of initial boundary value problems in linear micropolar thermoelastic mixtures. Logarithmic convexity arguments are used to establish results with no definiteness assumptions upon the internal energy.
Abstract: Dengue fever is an important human arboviral disease. Outbreaks are now reported quite often from many parts of the world. The number of cases involving pregnant women and infant cases are increasing every year. The illness is often severe and complications may occur. Deaths often occur because of the difficulties in early diagnosis and in the improper management of the diseases. Dengue antibodies from pregnant women are passed on to infants and this protects the infants from dengue infections. Antibodies from the mother are transferred to the fetus when it is still in the womb. In this study, we formulate a mathematical model to describe the transmission of this disease in pregnant women. The model is formulated by dividing the human population into pregnant women and non-pregnant human (men and non-pregnant women). Each class is subdivided into susceptible (S), infectious (I) and recovered (R) subclasses. We apply standard dynamical analysis to our model. Conditions for the local stability of the equilibrium points are given. The numerical simulations are shown. The bifurcation diagrams of our model are discussed. The control of this disease in pregnant women is discussed in terms of the threshold conditions.
Abstract: Motivated by Berman et al. [Sign patterns that allow eventual positivity, ELA, 19(2010): 108-120], we concentrate on the potential eventual positivity of irreducible tridiagonal sign patterns. The minimal potential eventual positivity of irreducible tridiagonal sign patterns of order less than six is established, and all the minimal potentially eventually positive tridiagonal sign patterns of order · 5 are identified. Our results indicate that if an irreducible tridiagonal sign pattern of order less than six A is minimal potentially eventually positive, then A requires the eventual positivity.
Abstract: The coalescer process is one of the methods for oily water treatment by increasing the oil droplet size in order to enhance the separating velocity and thus effective separation. However, the presence of surfactants in an oily emulsion can limit the obtained mechanisms due to the small oil size related with stabilized emulsion. In this regard, the purpose of this research is to improve the efficiency of the coalescer process for treating the stabilized emulsion. The effects of bed types, bed height, liquid flow rate and stage coalescer (step-bed) on the treatment efficiencies in term of COD values were studied. Note that the treatment efficiency obtained experimentally was estimated by using the COD values and oil droplet size distribution. The study has shown that the plastic media has more effective to attach with oil particles than the stainless one due to their hydrophobic properties. Furthermore, the suitable bed height (3.5 cm) and step bed (3.5 cm with 2 steps) were necessary in order to well obtain the coalescer performance. The application of step bed coalescer process in reactor has provided the higher treatment efficiencies in term of COD removal than those obtained with classical process. The proposed model for predicting the area under curve and thus treatment efficiency, based on the single collector efficiency (ηT) and the attachment efficiency (α), provides relatively a good coincidence between the experimental and predicted values of treatment efficiencies in this study.
Abstract: In this paper, a plane-strain orthotropic elasto-plastic
dynamic constitutive model is established, and with this constitutive
model, the thermal shock wave induced by intense pulsed X-ray
radiation in cylinder shell composite is simulated by the finite element
code, then the properties of thermal shock wave propagation are
discussed. The results show that the thermal shock wave exhibit
different shapes under the radiation of soft and hard X-ray, and while
the composite is radiated along different principal axes, great
differences exist in some aspects, such as attenuation of the peak stress
value, spallation and so on.
Abstract: Innovation, technology and knowledge are the trilogy
of impact to support the challenges arising from uncertainty.
Evidence showed an opportunity to ask how to manage in this
environment under constant innovation. In an attempt to get a
response from the field of Management Sciences, based in the
Contingency Theory, a research was conducted, with
phenomenological and descriptive approaches, using the Case Study
Method and the usual procedures for this task involving a focus
group composed of managers and employees working in the
pharmaceutical field. The problem situation was raised; the state of
the art was interpreted and dissected the facts. In this tasks were
involved four establishments. The result indicates that these focused
ventures have been managed by its founder empirically and is
experimenting agility described in this work. The expectation of this
study is to improve concepts for stakeholders on creativity in
business.
Abstract: This paper presents the results of a study aimed at
establishing the temperature distribution during the welding of
magnesium alloy sheets by Pulsed Current Gas Tungsten Arc
Welding (PCGTAW) and Constant Current Gas Tungsten Arc
Welding (CCGTAW) processes. Pulsing of the GTAW welding
current influences the dimensions and solidification rate of the fused
zone, it also reduces the weld pool volume hence a narrower bead. In
this investigation, the base material considered was 2mm thin AZ 31
B magnesium alloy, which is finding use in aircraft, automobile and
high-speed train components. A finite element analysis was carried
out using ANSYS, and the results of the FEA were compared with
the experimental results. It is evident from this study that the finite
element analysis using ANSYS can be effectively used to model
PCGTAW process for finding temperature distribution.
Abstract: In this study, workplace environmental monitoring
systems were established using USN(Ubiquitous Sensor Networks)
and LabVIEW. Although existing direct sampling methods enable
finding accurate values as of the time points of measurement, those
methods are disadvantageous in that continuous management and
supervision are difficult and costs for are high when those methods are
used. Therefore, the efficiency and reliability of workplace
management by supervisors are relatively low when those methods are
used. In this study, systems were established so that information on
workplace environmental factors such as temperatures, humidity and
noises is measured and transmitted to the PC in real time to enable
supervisors to monitor workplaces through LabVIEW on the PC.
When any accidents have occurred in workplaces, supervisors can
immediately respond through the monitoring system and this system
enables integrated workplace management and the prevention of
safety accidents. By introducing these monitoring systems, safety
accidents due to harmful environmental factors in workplaces can be
prevented and these monitoring systems will be also helpful in finding
out the correlation between safety accidents and occupational diseases
by comparing and linking databases established by this monitoring
system with existing statistical data.