Abstract: There is not much effective guideline on development of design parameters selection on spring back for advanced high strength steel sheet metal in U-channel process during cold forming process. This paper presents the development of predictive model for spring back in U-channel process on advanced high strength steel sheet employing Response Surface Methodology (RSM). The experimental was performed on dual phase steel sheet, DP590 in Uchannel forming process while design of experiment (DoE) approach was used to investigates the effects of four factors namely blank holder force (BHF), clearance (C) and punch travel (Tp) and rolling direction (R) were used as input parameters using two level values by applying Full Factorial design (24 ). From a statistical analysis of variant (ANOVA), result showed that blank holder force (BHF), clearance (C) and punch travel (Tp) displayed significant effect on spring back of flange angle (β2 ) and wall opening angle (β1 ), while rolling direction (R) factor is insignificant. The significant parameters are optimized in order to reduce the spring back behavior using Central Composite Design (CCD) in RSM and the optimum parameters were determined. A regression model for spring back was developed. The effect of individual parameters and their response was also evaluated. The results obtained from optimum model are in agreement with the experimental values.
Abstract: Community integration is a construct that an
increasing body of research has shown to have a significant impact
on the wellbeing and recovery of people with psychiatric problems.
However, there are few studies that explore which factors can be
associated and predict community integration. Moreover, community
integration has been mostly studied in minority groups, and current
literature on the definition and manifestation of community
integration in the general population is scarcer. Thus, the current
study aims to characterize community integration and explore
possible predictor variables in a sample of participants with
psychiatric problems (PP, N=183) and a sample of participants from
the general population (GP, N=211).
Results show that people with psychiatric problems present above
average values of community integration, but are significantly lower
than their healthy counterparts. It was also possible to observe that
community integration does not vary in terms of the sociodemographic
characteristics of both groups in this study. Correlation
and multiple regression showed that, among several variables that
literature present as relevant in the community integration process,
only three variables emerged as having the most explanatory value in
community integration of both groups: sense of community, basic
needs satisfaction and submission. These results also shown that
those variables have increased explanatory power in the PP sample,
which leads us to emphasize the need to address this issue in future
studies and increase the understanding of the factors that can be
involved in the promotion of community integration, in order to
devise more effective interventions in this field.
Abstract: This paper presents an optimization method for
reducing the number of input channels and the complexity of the
feed-forward NARX neural network (NN) without compromising the
accuracy of the NN model. By utilizing the correlation analysis
method, the most significant regressors are selected to form the input
layer of the NN structure. An application of vehicle dynamic model
identification is also presented in this paper to demonstrate the
optimization technique and the optimal input layer structure and the
optimal number of neurons for the neural network is investigated.
Abstract: The fatigue life of tubular joints commonly found in
offshore industry is not only dependent on the value of hot-spot stress
(HSS), but is also significantly influenced by the through-thethickness
stress distribution characterized by the degree of bending
(DoB). The determination of DoB values in a tubular joint is essential
for improving the accuracy of fatigue life estimation using the stresslife
(S–N) method and particularly for predicting the fatigue crack
growth based on the fracture mechanics (FM) approach. In the
present paper, data extracted from finite element (FE) analyses of
tubular KT-joints, verified against experimental data and parametric
equations, was used to investigate the effects of geometrical
parameters on DoB values at the crown 0°, saddle, and crown 180°
positions along the weld toe of central brace in tubular KT-joints
subjected to axial loading. Parametric study was followed by a set of
nonlinear regression analyses to derive DoB parametric formulas for
the fatigue analysis of KT-joints under axial loads. The tubular KTjoint
is a quite common joint type found in steel offshore structures.
However, despite the crucial role of the DoB in evaluating the fatigue
performance of tubular joints, this paper is the first attempt to study
and formulate the DoB values in KT-joints.
Abstract: Auditory hallucinations among the most invalidating
and distressing experiences reported by patients diagnosed with
schizophrenia, leading to feelings of powerlessness and helplessness
towards their illness. In more severe cases, these auditory
hallucinations can take the form of commanding voices, which are
often related to high suicidality rates in these patients. Several
authors propose that the meanings attributed to the hallucinatory
experience, rather than characteristics like form and content, can be
determinant in patients’ reactions to hallucinatory activity,
particularly in the case of voice-hearing experiences. In this study, 48
patients diagnosed with paranoid schizophrenia presenting auditory
hallucinations were studied. Multiple regression analyses were
computed to study the influence of several developmental aspects,
such as family and social dynamics, bullying, depression, and sociocognitive
variables on the auditory hallucinations, on patients’
attributions and relationships with their voices, and on the resulting
invalidation of hallucinatory experience. Overall, results showed how
relationships with voices can mirror several aspects of interpersonal
relationship with others, and how self-schemas, depression and actual
social relationships help shaping the voice-hearing experience. Early
experiences of victimization and submission help predict the
attributions of omnipotence of the voices, and increased hostility
from parents seems to increase the malevolence of the voices,
suggesting that socio-cognitive factors can significantly contribute to
the etiology and maintenance of auditory hallucinations. The
understanding of the characteristics of auditory hallucinations and the
relationships patients established with their voices can allow the
development of more promising therapeutic interventions that can be
more effective in decreasing invalidation caused by this devastating
mental illness.
Abstract: In statistics parameter theory, usually the
parameter estimations have two kinds, one is the least-square
estimation (LSE), and the other is the best linear unbiased
estimation (BLUE). Due to the determining theorem of
minimum variance unbiased estimator (MVUE), the parameter
estimation of BLUE in linear model is most ideal. But since
the calculations are complicated or the covariance is not
given, people are hardly to get the solution. Therefore, people
prefer to use LSE rather than BLUE. And this substitution
will take some losses. To quantize the losses, many scholars
have presented many kinds of different relative efficiencies in
different views. For the linear weighted regression model, this
paper discusses the relative efficiencies of LSE of β to BLUE
of β. It also defines two new relative efficiencies and gives
their lower bounds.
Abstract: The purpose of the paper is to estimate the US small
wind turbines market potential and forecast the small wind turbines
sales in the US. The forecasting method is based on the application of
the Bass model and the generalized Bass model of innovations
diffusion under replacement purchases. In the work an exponential
distribution is used for modeling of replacement purchases. Only one
parameter of such distribution is determined by average lifetime of
small wind turbines. The identification of the model parameters is
based on nonlinear regression analysis on the basis of the annual
sales statistics which has been published by the American Wind
Energy Association (AWEA) since 2001 up to 2012. The estimation
of the US average market potential of small wind turbines (for
adoption purchases) without account of price changes is 57080
(confidence interval from 49294 to 64866 at P = 0.95) under average
lifetime of wind turbines 15 years, and 62402 (confidence interval
from 54154 to 70648 at P = 0.95) under average lifetime of wind
turbines 20 years. In the first case the explained variance is 90,7%,
while in the second - 91,8%. The effect of the wind turbines price
changes on their sales was estimated using generalized Bass model.
This required a price forecast. To do this, the polynomial regression
function, which is based on the Berkeley Lab statistics, was used. The
estimation of the US average market potential of small wind turbines
(for adoption purchases) in that case is 42542 (confidence interval
from 32863 to 52221 at P = 0.95) under average lifetime of wind
turbines 15 years, and 47426 (confidence interval from 36092 to
58760 at P = 0.95) under average lifetime of wind turbines 20 years.
In the first case the explained variance is 95,3%, while in the second
– 95,3%.
Abstract: Al6061 alloy base matrix, reinforced with particles of
silicon carbide (10 wt %) and Graphite powder (1wt%), known as
hybrid composites have been fabricated by liquid metallurgy route
(stir casting technique) and optimized at different parameters like
applied load, sliding speed and sliding distance by taguchi method. A
plan of experiment generated through taguchi technique was used to
perform experiments based on L27 orthogonal array. The developed
ANOVA and regression equations are used to find the optimum
coefficient of friction and wear under the influence of applied load,
sliding speed and sliding distance. On the basis of “smaller the best”
the dry sliding wear resistance was analysed and finally confirmation
tests were carried out to verify the experimental results.
Abstract: This paper presents a rank correlation curve. The
traditional correlation coefficient is valid for both continuous
variables and for integer variables using rank statistics. Since
the correlation coefficient has already been established in rank
statistics by Spearman, such a calculation can be extended to
the correlation curve.
This paper presents two survey questions. The survey
collected non-continuous variables. We will show weak to
moderate correlation. Obviously, one question has a negative
effect on the other. A review of the qualitative literature
can answer which question and why. The rank correlation
curve shows which collection of responses has a positive
slope and which collection of responses has a negative slope.
Such information is unavailable from the flat, ”first-glance”
correlation statistics.
Abstract: In this paper, a model is proposed to determine the life
distribution parameters of the useful life region for the PV system
utilizing a combination of non-parametric and linear regression
analysis for the failure data of these systems. Results showed that this
method is dependable for analyzing failure time data for such reliable
systems when the data is scarce.
Abstract: Prosperity of electronic equipment in photocopying
environment not only has improved work efficiency, but also has
changed indoor air quality. Considering the number of photocopying
employed, indoor air quality might be worse than in general office
environments. Determining the contribution from any type of
equipment to indoor air pollution is a complex matter. Non-methane
hydrocarbons are known to have an important role on air quality due
to their high reactivity. The presence of hazardous pollutants in
indoor air has been detected in one photocopying shop in Novi Sad,
Serbia. Air samples were collected and analyzed for five days, during
8-hr working time in three time intervals, whereas three different
sampling points were determined. Using multiple linear regression
model and software package STATISTICA 10 the concentrations of
occupational hazards and microclimates parameters were mutually
correlated. Based on the obtained multiple coefficients of
determination (0.3751, 0.2389 and 0.1975), a weak positive
correlation between the observed variables was determined. Small
values of parameter F indicated that there was no statistically
significant difference between the concentration levels of nonmethane
hydrocarbons and microclimates parameters. The results
showed that variable could be presented by the general regression
model: y = b0 + b1xi1+ b2xi2. Obtained regression equations allow to
measure the quantitative agreement between the variables and thus
obtain more accurate knowledge of their mutual relations.
Abstract: This paper analyzes the conceptual framework of three
statistical methods, multiple regression, path analysis, and structural
equation models. When establishing research model of the statistical
modeling of complex social phenomenon, it is important to know the
strengths and limitations of three statistical models. This study
explored the character, strength, and limitation of each modeling and
suggested some strategies for accurate explaining or predicting the
causal relationships among variables. Especially, on the studying of
depression or mental health, the common mistakes of research
modeling were discussed.
Abstract: Polymer Electrolyte Membrane Fuel Cell (PEMFC) is
such a time-vary nonlinear dynamic system. The traditional linear
modeling approach is hard to estimate structure correctly of PEMFC
system. From this reason, this paper presents a nonlinear modeling of
the PEMFC using Neural Network Auto-regressive model with
eXogenous inputs (NNARX) approach. The multilayer perception
(MLP) network is applied to evaluate the structure of the NNARX
model of PEMFC. The validity and accuracy of NNARX model are
tested by one step ahead relating output voltage to input current from
measured experimental of PEMFC. The results show that the obtained
nonlinear NNARX model can efficiently approximate the dynamic
mode of the PEMFC and model output and system measured output
consistently.
Abstract: The present study was carried out to investigate the
effect of alloying elements and thermo-mechanical treatment (TMT)
i.e. hot rolling and forging with different reduction ratios on the
hardness (HV) and impact toughness (J) of heat-treated low alloy
steels. An understanding of the combined effect of TMT and alloying
elements and by measuring hardness, impact toughness, resulting
from different heat treatment following TMT of the low alloy steels,
it is possible to determine which conditions yielded optimum
mechanical properties and high strength to weight ratio.
Experimental Correlations between hot work reduction ratio,
hardness and impact toughness for thermo-mechanically heat treated
low alloy steels are analyzed quantitatively, and both regression and
mathematical hardness and impact toughness models are developed.
Abstract: Introduction: There are multiple social, individual and
cultural factors that influence an individual’s decision to adopt family
planning methods especially among non-users in patriarchal societies
like Pakistan. Non-users, if targeted efficiently, can contribute
significantly to country’s CPR. A research study showed that nonusers
if convinced to adopt lactational amenorrhea method can shift
to long term methods in future. Research shows that if non users are
targeted efficiently a 59% reduction in unintended pregnancies in
Saharan Africa and South-Central and South-East Asia is anticipated.
Methods: We did secondary data analysis on Pakistan
Demographic Heath Survey (2012-13) dataset. Use of contraception
(never-use/ever-use) was the outcome variable. At univariate level
Chi-square/Fisher Exact test was used to assess relationship of
baseline covariates with contraception use. Then variables to be
incorporated in the model were checked for multicollinearity,
confounding and interaction. Then binary logistic regression (with an
urban-rural stratification) was done to find relationship between
contraception use and baseline demographic and social variables.
Results: The multivariate analyses of the study showed that
younger women (≤ 29 years)were more prone to be never users as
compared to those who were >30 years and this trend was seen in
urban areas (AOR 1.92, CI 1.453-2.536) as well as rural areas (AOR
1.809, CI 1.421-2.303). While looking at regional variation, women
from urban Sindh (AOR 1.548, CI 1.142-2.099) and urban
Balochistan (AOR 2.403, CI 1.504-3.839) had more never users as
compared to other urban regions. Women in the rich wealth quintile
were more never users and this was seen both in urban and rural
localities (urban (AOR 1.106 CI .753-1.624); rural areas (AOR 1.162,
CI .887-1.524)) even though these were not statistically significant.
Women idealizing more children (>4) are more never users as
compared to those idealizing less children in both urban (AOR 1.854,
CI 1.275-2.697) and rural areas (AOR 2.101, CI 1.514-2.916).
Women who never lost a pregnancy were more inclined to be nonusers
in rural areas (AOR 1.394, CI 1.127-1.723) .Women familiar
with only traditional or no method had more never users in rural areas
(AOR 1.717, CI 1.127-1.723) but in urban areas it wasn’t significant.
Women unaware of Lady Health Worker’s presence in their area
were more never users especially in rural areas (AOR 1.276, CI
1.014-1.607). Women who did not visit any care provider were more
never users (urban (AOR 11.738, CI 9.112-15.121) rural areas (AOR
7.832, CI 6.243-9.826)).
Discussion/Conclusion: This study concluded that government,
policy makers and private sector family planning programs should
focus on the untapped pool of never users (younger women from underserved provinces, in higher wealth quintiles, who desire more
children.). We need to make sure to cover catchment areas where
there are less LHWs and less providers as ignorance to modern
methods and never been visited by an LHW are important
determinants of never use. This all is in sync with previous literate
from similar developing countries.
Abstract: This study attempts to identify the factors influencing
on women empowerment of rural area in Sri Lanka through micro
finance services. Data were collected from one hundred (100) rural
women involving self-employment activities through a questionnaire
using direct personal interviews. Judgment and Convenience Random
sampling technique was used to select the sample size from three
Divisional Secretariat divisions of Kandawalai, Poonakari and
Karachchi in Kilinochchi District. The factor analysis was performed
on fourteen (14) variables for screening and reducing the variables to
identify the influencing factors on empowerment. Multiple regression
analysis was used to identify the relationship between the three
empowerment factors and the impact of micro finance on overall
empowerment of rural women. The result of this study summarized
the variables into three factors namely decision making, freedom to
mobility and family support and which are positively associated with
empowerment. In addition to this the value of adjusted R2 is 0.248
indicates that all the variables extracted can be explained 24.8% of
the variation in the women empowerment through microfinance.
Independent variables of these three factors have positive correlation
with women empowerment as well as significant values at 5 percent
level.
Abstract: Moringa oleifera is a nutritious vegetable tree with
varieties of potential uses, as almost every part of the Moringa
oleifera tree can be used for food. This study was conducted in Oyo
State, Nigeria, to find out the level of acceptability of Moringa
oleifera diversified products among rural and urban dwellers.
Purposive sampling was used to select two local governments’ areas.
Stratified sampling technique was also used to select one community
each from rural and urban areas while snowball sampling technique
was used to select ten respondents each from the two communities,
making a total number of forty respondents. Data were analyzed
using frequencies, percentages, Chi-square, Pearson Product Moment
Correlation and regression analysis. Result from the study revealed
that majority of the respondents (80%) fell within the age range of
20-49 years and 55% of them were male, 55% were married, 70% of
them were Christians, 80% of them had tertiary education. The result
also showed that 85% were aware of the Moringa plant and (65%) of
them have consumed Moringa oleifera and the perception statements
on the benefits of Moringa oleifera indicated that (52.5%) of the
respondents rated Moringa oleifera to be favorable, most of them had
high acceptability for Moringa egusi soup, Moringa tea, Moringa pap
and yam pottage with Moringa. The result of the hypotheses testing
showed that there is a significant relationship between sex of the
respondents and acceptability of the diversified Moringa oleifera
products (x2=6.465, p = 0.011). There is also a significant
relationship between family size of the respondents level of
acceptability of the Moringa oleifera products (r = 0.327, p = 0.040).
Based on the level of acceptability of Moringa oleifera diversified
products; the plant is of great economic importance to the populace.
Therefore, there should be more public awareness through the media
to enlighten people on the beneficial effects of Moringa oleifera.
Abstract: The research of juice flavor forecasting has become
more important in China. Due to the fast economic growth in China,
many different kinds of juices have been introduced to the market. If a
beverage company can understand their customers’ preference well,
the juice can be served more attractive. Thus, this study intends to
introducing the basic theory and computing process of grapes juice
flavor forecasting based on support vector regression (SVR). Applying
SVR, BPN, and LR to forecast the flavor of grapes juice in real data
shows that SVR is more suitable and effective at predicting
performance.
Abstract: Ulexite (Na2O.2CaO.5B2O3.16H2O) is boron mineral
that is found in large quantities in the Turkey and world. In this
study, the dissolution of this mineral in the disodium hydrogen
phosphate solutions has been studied. Temperature, concentration,
stirring speed, solid liquid ratio and particle size were selected as
parameters. The experimental results were successfully correlated by
linear regression using Statistica program. Dissolution curves were
evaluated shrinking core models for solid-fluid systems. It was
observed that increase in the reaction temperature and decrease in the
solid/liquid ratio causes an increase the dissolution rate of ulexite.
The activation energy was found to be 63.4 kJ/mol. The leaching of
ulexite was controlled by chemical reaction.
Abstract: A total of 115 yeast strains isolated from local cassava
processing wastes were measured for crude protein content. Among
these strains, the strain MSY-2 possessed the highest protein
concentration (>3.5 mg protein/mL). By using molecular
identification tools, it was identified to be a strain of Pichia
kudriavzevii based on similarity of D1/D2 domain of 26S rDNA
region. In this study, to optimize the protein production by MSY-2
strain, Response Surface Methodology (RSM) was applied. The
tested parameters were the carbon content, nitrogen content, and
incubation time. Here, the value of regression coefficient (R2) =
0.7194 could be explained by the model which is high to support the
significance of the model. Under the optimal condition, the protein
content was produced up to 3.77 g per L of the culture and MSY-2
strain contains 66.8 g protein per 100 g of cell dry weight. These
results revealed the plausibility of applying the novel strain of yeast
in single-cell protein production.