Abstract: This study investigates the causes, effects and remedies of traffic congestion which has become a common sight in most highways in Nigeria; Mowe/Ibafo section of the Lagos-Ibadan expressway was used as the case-study. 300 Structured questionnaires were distributed among the road users comprising drivers (Private and Commercial), passengers, pedestrians, traffic officers, church congregations, community leaders, Mowe/Ibafo residents, and other users of the road.
300 questionnaires were given out; the average of 276 well completed returned questionnaires formed the basis of the study and was analyzed by the Relative Importance Index (R.I.I.). The result from the study showed the causes of traffic congestion as inadequate road capacity, poor road pavement, poor traffic management, poor drainage system poor driving habit, poor parking habit, poor design junctions/round-about, presence of heavy trucks, lack of pedestrian facilities, lack of road furniture, lack of parking facilities and others. Effects of road congestion from the study are waste of time, delay movement, stress, accident, inability to forecast travel of time, fuel consumption, road rage, relocation, night driving, and environmental pollution. To drastically reduce these negative effects; there must be provision for adequate parking space, construction of proper drainage, enlarging the width of the road, rehabilitate all roads needing attention, public enlightenment, traffic education, hack down all illegal buildings/shops built on the right of way (ROW), create a separate/alternative root for trucks and heavy vehicles, provision of pedestrian facilities, In-depth training of transport/traffic personnel, ban all form of road trading/hawking, and reduce the number of bus-stop where necessary. It is hoped that this study will become the foundation of further research in the area of improve road traffic management on our major highway.
Abstract: This paper presents a visualized computer aided case tool for non-expert, called Visual Time, for representing and reasoning about incomplete and uncertain temporal information. It is both expressive and versatile, allowing logical conjunctions and disjunctions of both absolute and relative temporal relations, such as “Before”, “Meets”, “Overlaps”, “Starts”, “During”, and “Finishes”, etc. In terms of a visualized framework, Visual Time provides a user-friendly environment for describing scenarios with rich temporal structure in natural language, which can be formatted as structured temporal phrases and modeled in terms of Temporal Relationship Diagrams (TRD). A TRD can be automatically and visually transformed into a corresponding Time Graph, supported by automatic consistency checker that derives a verdict to confirm if a given scenario is temporally consistent or inconsistent.
Abstract: Human society, there are many uncertainties, such as economic growth rate forecast of the financial crisis, many scholars have, since the the Song Chissom two scholars in 1993 the concept of the so-called fuzzy time series (Fuzzy Time Series)different mode to deal with these problems, a previous study, however, usually does not consider the relevant variables selected and fuzzy process based solely on subjective opinions the fuzzy semantic discrete, so can not objectively reflect the characteristics of the data set, in addition to carrying outforecasts are often fuzzy rules as equally important, failed to consider the importance of each fuzzy rule. For these reasons, the variable selection (Factor Selection) through self-organizing map (Self-Organizing Map, SOM) and proposed high-end weighted multivariate fuzzy time series model based on fuzzy neural network (Fuzzy-BPN), and using the the sequential weighted average operator (Ordered Weighted Averaging operator, OWA) weighted prediction. Therefore, in order to verify the proposed method, the Taiwan stock exchange (Taiwan Stock Exchange Corporation) Taiwan Weighted Stock Index (Taiwan Stock Exchange Capitalization Weighted Stock Index, TAIEX) as experimental forecast target, in order to filter the appropriate variables in the experiment Finally, included in other studies in recent years mode in conjunction with this study, the results showed that the predictive ability of this study further improve.
Abstract: In this paper we use low frequency noise analysis to understand and map the current conduction path in a multi gate junctionless FinFET. The device used in this study behaves as a gated resistor and shows excellent short channel effect suppression due to its multi gate structure. Generally for a bulk conduction device like the junctionless device studied in this work, the low frequency noise can be modelled using the mobility fluctuation model; however for this device we can also see the effect of carrier fluctuations on the LFN characteristic. The noise characteristic at different gate bias and also the possible location of the traps is explained.
Abstract: This paper presents device simulations on the vertical silicon nanowire tunneling FET (VSiNW TFET). Simulations show that a narrow nanowire and thin gate oxide is required for good performance, which is expected even for conventional MOSFETs. The gate length also needs to be more than the nanowire diameter to prevent short channel effects. An effect more unique to TFET is the need for abrupt source to channel junction, which is shown to improve the performance. The ambipolar effect suppression by reducing drain doping concentration is also explored and shown to have little or no effect on performance.
Abstract: This paper proposes a stroke extraction method for use in off-line signature verification. After giving a brief overview of the current ongoing researches an algorithm is introduced for detecting and following strokes in static images of signatures. Problems like the handling of junctions and variations in line width and line intensity are discussed in detail. Results are validated by both using an existing on-line signature database and by employing image registration methods.
Abstract: By the end of XX century in the structure of humanity some changes have been provoked: a new ethnos - Ethnos of Intellect is formed and is still being formed, beside the historical types of ethnoses: open ethnos, closed ethnos, wandering ethnos, dead ethnos, - and this event was caused by the technical progress, development of informational and transport communications, especially - by creation of Internet. The Ethnos of Intellect is something very close to the ÔÇ×Information Society“ described by J. Ellule and Y. Masuda that was regarded as the culture of XXI century, being an antithesis for technical and technicistical civilizations, but it-s necessary to indicate also the essential difference between these concepts: the Ethnos of Intellect is the antithesis of Socium. The existence of such an ethnos within human society that has already become an Information Society itself is extremely important in observing legally and informatically a new kind of reins in the hands of the political power, revealing every attempt to violate the human rights of simple citizens. A concrete example of some conjunction points of legal informatics and informatical law in a certain kind of ambiental studies of the project ''State Registre of Population'' in Russia is very eloquent.
Abstract: In this study we present the effect of elevated
temperatures from 300K to 400K on the electrical properties of
copper Phthalocyanine (CuPc) based organic field effect transistors
(OFET). Thin films of organic semiconductor CuPc (40nm) and
semitransparent Al (20nm) were deposited in sequence, by vacuum
evaporation on a glass substrate with previously deposited Ag source
and drain electrodes with a gap of 40 μm. Under resistive mode of
operation, where gate was suspended it was observed that drain
current of this organic field effect transistor (OFET) show an
increase with temperature. While in grounded gate condition metal
(aluminum) – semiconductor (Copper Phthalocyanine) Schottky
junction dominated the output characteristics and device showed
switching effect from low to high conduction states like Zener diode
at higher bias voltages. This threshold voltage for switching effect
has been found to be inversely proportional to temperature and shows
an abrupt decrease after knee temperature of 360K. Change in
dynamic resistance (Rd = dV/dI) with respect to temperature was
observed to be -1%/K.
Abstract: In the present study, computational fluid dynamics
(CFD) simulation has been executed to investigate the transition
boundaries of different flow patterns for moderately viscous oil-water
(viscosity ratio 107, density ratio 0.89 and interfacial tension of 0.032
N/m.) two-phase flow through a horizontal pipeline with internal
diameter and length of 0.025 m and 7.16 m respectively. Volume of
Fluid (VOF) approach including effect of surface tension has been
employed to predict the flow pattern. Geometry and meshing of the
present problem has been drawn using GAMBIT and ANSYS
FLUENT has been used for simulation. A total of 47037 quadrilateral
elements are chosen for the geometry of horizontal pipeline. The
computation has been performed by assuming unsteady flow,
immiscible liquid pair, constant liquid properties, co-axial flow and a
T-junction as entry section. The simulation correctly predicts the
transition boundaries of wavy stratified to stratified mixed flow.
Other transition boundaries are yet to be simulated. Simulated data
has been validated with our own experimental results.
Abstract: In the Equivalent Transformation (ET) computation
model, a program is constructed by the successive accumulation of
ET rules. A method by meta-computation by which a correct ET
rule is generated has been proposed. Although the method covers a
broad range in the generation of ET rules, all important ET rules
are not necessarily generated. Generation of more ET rules can be
achieved by supplementing generation methods which are specialized
for important ET rules. A Specialization-by-Equation (Speq) rule is
one of those important rules. A Speq rule describes a procedure in
which two variables included in an atom conjunction are equalized
due to predicate constraints. In this paper, we propose an algorithm
that systematically and recursively generate Speq rules and discuss
its effectiveness in the synthesis of ET programs. A Speq rule is
generated based on proof of a logical formula consisting of given
atom set and dis-equality. The proof is carried out by utilizing some
ET rules and the ultimately obtained rules in generating Speq rules.
Abstract: Photo-BJMOSFET (Bipolar Junction Metal-Oxide-
Semiconductor Field Effect Transistor) fabricated on SOI film was proposed. ITO film is adopted in the device as gate electrode to reduce
light absorption. Depletion region but not inversion region is formed
in film by applying gate voltage (but low reverse voltage) to achieve
high photo-to-dark-current ratio. Comparisons of photoelectriccharacteristics
executed among VGK=0V, 0.3V, 0.6V, 0.9V and 1.0V
(reverse voltage VAK is equal to 1.0V for total area of 10×10μm2). The
results indicate that the greatest improvement in photo-to-dark-current
ratio is achieved up to 2.38 at VGK=0.6V. In addition,
photo-BJMOSFET is compatible with CMOS integration due to big
input resistance
Abstract: The aim of the current work is to present a comparison among three popular optimization methods in the inverse elastostatics problem (IESP) of flaw detection within a solid. In more details, the performance of a simulated annealing, a Hooke & Jeeves and a sequential quadratic programming algorithm was studied in the test case of one circular flaw in a plate solved by both the boundary element (BEM) and the finite element method (FEM). The proposed optimization methods use a cost function that utilizes the displacements of the static response. The methods were ranked according to the required number of iterations to converge and to their ability to locate the global optimum. Hence, a clear impression regarding the performance of the aforementioned algorithms in flaw identification problems was obtained. Furthermore, the coupling of BEM or FEM with these optimization methods was investigated in order to track differences in their performance.
Abstract: The effect of autofrettage process in strain hardened
thick-walled pressure vessels has been investigated theoretically by
finite element modeling. Equivalent von Mises stress is used as yield
criterion to evaluate the optimum autofrettage pressure and the
optimum radius of elastic-plastic junction. It has been observed that
the optimum autofrettage pressure increases along with the working
pressure. For two different working pressures, the effect of the ratio
of outer to inner radius (b/a=k) value on the optimum autofrettage
pressure is also noticed. The Optimum autofrettage pressure solely
depends on K value rather than on the inner or outer radius.
Furthermore, percentage reduction of von Mises stresses is compared
for different working pressures and different k values. Maximum von
Mises stress developed at different autofrettage pressure is equated
for elastic perfectly plastic and elastic-plastic material with different
slope of strain hardening segment. Cylinder material having higher
slope of strain hardening segment provides better benedictions in the
autofrettage process.
Abstract: The steady state response of bond graphs representing
passive and active suspension is presented. A bond graph with
preferred derivative causality assignment to get the steady state
is proposed. A general junction structure of this bond graph
is proposed. The proposed methodology to passive and active
suspensions is applied.
Abstract: Field experiments were conducted at Annamalai University Experimental Farm, Department of Agronomy; to device suitable weed control measures for direct seeded puddled rice and to study the effect of the weed control measures on the soil microbial population. The treatments comprised of incorporation of pressmud @ 6.25 t ha-1 and application of herbicide butachlor @1.5 kg a. i. ha- 1 with and without safener 4 days after sowing (DAS), 8 DAS alone and also in conjunction with hand weeding at 30 DAS. Hand weeding twice and a weedy check were also maintained. At maximum tillering stage, the population of bacteria was significantly reduced by butachlor application. The injury to microbes caused by herbicide disappeared with the advancement of crop's age and at flowering stage of crop, there was no significant difference among the treatments. The fungal and actinomycetes population remained unaltered by weed control treatments at both the stages of observation.
Abstract: Tip vortex cavitation is one of well known patterns of
cavitation phenomenon which occurs in axial pumps. This pattern of
cavitation occurs due to pressure difference between the pressure and
suction sides of blades of an axial pump. Since the pressure in the
pressure side of the blade is higher than the pressure in its suction
side, thus a very small portion of liquid flow flows back from
pressure side to the suction side. This fact is cause of tip vortex
cavitation and gap cavitation that may occur in axial pumps. In this
paper the results of our experimental investigation about movement
of tip vortex cavitation along blade edge due to reduction of pump
flow rate in an axial pump is reported. Results show that reduction of
pump flow rate in conjunction with increasing of outlet pressure
causes movement of tip vortex cavitation along blade edge towards
the blade tip. Results also show that by approaching tip vortex
cavitation to the blade tip, vortex tip pattern of cavitation replaces
with a cavitation phenomenon on the blade tip. Furthermore by
further reduction of pump flow rate and increasing of outlet pressure,
an unstable cavitation phenomenon occurs between each blade
leading edge and the next blade trailing edge.
Abstract: This study fabricates p-type Ni1−xO:Li/n-Si heterojunction solar cells (P+/n HJSCs) by using radio frequency (RF) magnetron sputtering and investigates the effect of substrate temperature on photovoltaic cell properties. Grazing incidence x-ray diffraction, four point probe, and ultraviolet-visible-near infrared discover the optoelectrical properties of p-Ni1-xO thin films. The results show that p-Ni1-xO thin films deposited at 300 oC has the highest grain size (22.4 nm), average visible transmittance (~42%), and electrical resistivity (2.7 Ωcm). However, the conversion efficiency of cell is shown only 2.33% which is lower than the cell (3.39%) fabricated at room temperature. This result can be mainly attributed to interfacial layer thickness (SiOx) reduces from 2.35 nm to 1.70 nm, as verified by high-resolution transmission electron microscopy.
Abstract: The relationship between different types of Molybdenum disulfide greases under extreme pressure loading and different speed situations have been studied using Design of Experiment (DOE) under 1200rpm steady state rotational speed and cyclic frequencies between 2400 and 1200rpm using a Plint machine software to set up the different rotational speed situations.
Research described here is aimed at providing good friction and wear performance while optimizing cyclic frequencies and MoS2 concentration due to the recent concern about grease behavior in extreme pressure applications. Extreme load of 785 Newton was used in conjunction with different cyclic frequencies (2400rpm -3.75min, 1200rpm -7.5min, 2400rpm -3.75min, 1200rpm -7.5min), to examine lithium based grease with and without MoS2 for equal number of revolutions, and a total run of 36000 revolutions; then compared to 1200rpm steady speed for the same total number of revolutions. 4 Ball wear tester was utilized to run large number of experiments randomly selected by the DOE software. The grease was combined with fine grade MoS2 or technical grade then heated to 750C and the wear scar width was collected at the end of each test. DOE model validation results verify that the data were very significant and can be applied to a wide range of extreme pressure applications. Based on simulation results and Scanning Electron images (SEM), it has been found that wear was largely dependent on the cyclic frequency condition. It is believed that technical grade MoS2 greases under faster cyclic speeds perform better and provides antiwear film that can resist extreme pressure loadings. Figures showed reduced wear scars width and improved frictional values.
Abstract: In this paper, a bond graph dynamic model for a valvecontrolled
hydraulic cylinder has been developed. A simplified bond
graph model of the inter-actuator interactions in a multi-cylinder
hydraulic system has also been presented. The overall bond graph
model of a valve-controlled hydraulic cylinder was developed by
combining the bond graph sub-models of the pump, spool valve and
the actuator using junction structures. Causality was then assigned
in order to obtain a computational model which could be simulated.
The causal bond graph model of the hydraulic cylinder was verified
by comparing the open loop state responses to those of an ODE
model which had been developed in literature based on the same
assumptions. The results were found to correlate very well both
in the shape of the curves, magnitude and the response times,
thus indicating that the developed model represents the hydraulic
dynamics of a valve-controlled cylinder. A simplified model for interactuator
interaction was presented by connecting an effort source with
constant pump pressure to the zero-junction from which the cylinders
in a multi-cylinder system are supplied with a constant pressure from
the pump. On simulating the state responses of the developed model
under different situations of cylinder operations, indicated that such
a simple model can be used to predict the inter-actuator interactions.
Abstract: Whit the increasing of traffic, noise emanated from
motor vehicles increases as well, which subsequently causes adding
to the stress of modern city. Thus, it is needed to look for most
critical areas in terms of environmental and social impact of noise.
There are several critical situations for noise emanated from motor
vehicles such as stop and go situation which usually occurs near
junctions or at-grade intersections. This study was conducted in two
locations, most common types of intersections, crossroads and Tjunctions.
The highest average noise levels are recorded during Go
phase for T-junction, 64.4 dB, and Drive phase for crossroad, 64 dB.
It implies that the existence of intersection caused the noise level to
increase. The vehicles starting to move produce more sound than
when they travel at a constant speed along the intersection. It is
suggested that special considerations and priority of allocating funds
should be given to these critical spots.