Abstract: The sintering step in powder metallurgy (P/M) processes is very sensitive as it determines to a large extent the properties of the final component produced. Spark plasma sintering over the past decade has been extensively used in consolidating a wide range of materials including metallic alloy powders. This novel, non-conventional sintering method has proven to be advantageous offering full densification of materials, high heating rates, low sintering temperatures, and short sintering cycles over conventional sintering methods. Ti6Al4V has been adjudged the most widely used α+β alloy due to its impressive mechanical performance in service environments, especially in the aerospace and automobile industries being a light metal alloy with the capacity for fuel efficiency needed in these industries. The P/M route has been a promising method for the fabrication of parts made from Ti6Al4V alloy due to its cost and material loss reductions and the ability to produce near net and intricate shapes. However, the use of this alloy has been largely limited owing to its relatively poor hardness and wear properties. The effect of sintering temperature on the densification, hardness, and wear behaviors of spark plasma sintered Ti6Al4V powders was investigated in this present study. Sintering of the alloy powders was performed in the 650–850°C temperature range at a constant heating rate, applied pressure and holding time of 100°C/min, 50 MPa and 5 min, respectively. Density measurements were carried out according to Archimedes’ principle and microhardness tests were performed on sectioned as-polished surfaces at a load of 100gf and dwell time of 15 s. Dry sliding wear tests were performed at varied sliding loads of 5, 15, 25 and 35 N using the ball-on-disc tribometer configuration with WC as the counterface material. Microstructural characterization of the sintered samples and wear tracks were carried out using SEM and EDX techniques. The density and hardness characteristics of sintered samples increased with increasing sintering temperature. Near full densification (99.6% of the theoretical density) and Vickers’ micro-indentation hardness of 360 HV were attained at 850°C. The coefficient of friction (COF) and wear depth improved significantly with increased sintering temperature under all the loading conditions examined, except at 25 N indicating better mechanical properties at high sintering temperatures. Worn surface analyses showed the wear mechanism was a synergy of adhesive and abrasive wears, although the former was prevalent.
Abstract: A methodology based on wavelets is proposed for the automatic location and delimitation of defects in limestone plates. Natural defects include dark colored spots, crystal zones trapped in the stone, areas of abnormal contrast colors, cracks or fracture lines, and fossil patterns. Although some of these may or may not be considered as defects according to the intended use of the plate, the goal is to pair each stone with a map of defects that can be overlaid on a computer display. These layers of defects constitute a database that will allow the preliminary selection of matching tiles of a particular variety, with specific dimensions, for a requirement of N square meters, to be done on a desktop computer rather than by a two-hour search in the storage park, with human operators manipulating stone plates as large as 3 m x 2 m, weighing about one ton. Accident risks and work times are reduced, with a consequent increase in productivity. The base for the algorithm is wavelet decomposition executed in two instances of the original image, to detect both hypotheses – dark and clear defects. The existence and/or size of these defects are the gauge to classify the quality grade of the stone products. The tuning of parameters that are possible in the framework of the wavelets corresponds to different levels of accuracy in the drawing of the contours and selection of the defects size, which allows for the use of the map of defects to cut a selected stone into tiles with minimum waste, according the dimension of defects allowed.
Abstract: Vacuum flat plate solar thermal collectors offer several advantages over other collectors namely the excellent optical and thermal characteristics they exhibit due to a combination of their wide surface area and high vacuum thermal insulation. These characteristics can offer a variety of applications for industrial process heat as well as for building integration as they are much thinner than conventional collectors making installation possible in limited spaces. However, many technical challenges which need to be addressed to enable wide scale adoption of the technology still remain. This paper will discuss the challenges, expectations and requirements for the flat-plate vacuum solar collector development. In addition, it will provide an overview of work undertaken in Ulster University, Loughborough University, and the University of Warwick on flat-plate vacuum solar thermal collectors. Finally, this paper will present a detailed experimental investigation on the development of a vacuum panel with a novel sealing method which will be used to accommodate a novel slim hydroformed solar absorber.
Abstract: This study is aimed to investigate the influence of
postharvest delays of 1-Methylcyclopropene (1-MCP) treatment on
prolonging the storage potential of melon. Melons were treated with
625-650 ppb 1-MCP at 10 °C for 24 hours on the 1st, 3rd and 5th day
after harvest. Decreased ethylene production and retarded softening
of melon fruits after 7 days of storage at 10 °C plus 3 days of shelflife
were obtained by 1-MCP applications. 1-MCP strongly affected
the chlorophyll fluorescence characteristics and hue angle values of
melon. After shelf-life, the peel color of treated melon was slow in
turning to yellow compared to the control. Additionally, firmness of
melons treated on the first day after harvest was 38% higher than that
of the control fruit. Results showed that fruits treated on the 1st and
the 3rd day after harvest could maintain the quality of melon.
Abstract: In addition to the fact that mental health bears great significance to a particular individual, it can also be regarded as an organizational, community and societal resource. Within the Szeged Health Promotion Research Group, we conducted mental health surveys on two levels: The inhabitants of a medium-sized Hungarian town and students of a Hungarian university with a relatively big headcount were requested to participate in surveys whose goals were to define local government priorities and organization-level health promotion programmes, respectively. To facilitate professional decision-making, we defined three, pragmatically relevant, groups of the target population: the mentally healthy, the vulnerable and the endangered. In order to determine which group a person actually belongs to, we designed a simple and quick measurement tool, which could even be utilised as a smoothing method, the Mental State Questionnaire validity of the above three categories was verified by analysis of variance against psychological quality of life variables. We demonstrate the pragmatic significance of our method via the analyses of the scores of our two mental health surveys. On town level, during our representative survey in Hódmezővásárhely (N=1839), we found that 38.7% of the participants was mentally healthy, 35.3% was vulnerable, while 16.3% was considered as endangered. We were able to identify groups that were in a dramatic state in terms of mental health. For example, such a group consisted of men aged 45 to 64 with only primary education qualification and the ratios of the mentally healthy, vulnerable and endangered were 4.5, 45.5 and 50%, respectively. It was also astonishing to see to what a little extent qualification prevailed as a protective factor in the case of women. Based on our data, the female group aged 18 to 44 with primary education—of whom 20.3% was mentally healthy, 42.4% vulnerable and 37.3% was endangered—as well as the female group aged 45 to 64 with university or college degree—of whom 25% was mentally healthy, 51.3 vulnerable and 23.8% endangered—are to be handled as priority intervention target groups in a similarly difficult position. On organizational level, our survey involving the students of the University of Szeged, N=1565, provided data to prepare a strategy of mental health promotion for a university with a headcount exceeding 20,000. When developing an organizational strategy, it was important to gather information to estimate the proportions of target groups in which mental health promotion methods; for example, life management skills development, detection, psychological consultancy, psychotherapy, would be applied. Our scores show that 46.8% of the student participants were mentally healthy, 42.1% were vulnerable and 11.1% were endangered. These data convey relevant information as to the allocation of organizational resources within a university with a considerable headcount. In conclusion, The Mental State Questionnaire, as a valid smoothing method, is adequate to describe a community in a plain and informative way in the terms of mental health. The application of the method can promote the preparation, design and implementation of mental health promotion interventions.
Abstract: This research investigates the impact of Brand Loyalty on the product performance and the factors those are considered more important in brand reputation. Variables selected for this research are Brand quality, Brand Equity, Brand Reputation to explore the impact of these variables on Product performance. For this purpose, primary research has been conducted. The questionnaire survey for this research study was administered among the population mainly at the shopping malls. For this research study, a sample size of 250 respondents has been taken into consideration. Customers from the shopping malls and university students constitute the sample for this research study using random sampling (non-probabilistic) used as a sampling technique for conducting the research survey. According to the results obtained from the collected data, it is interpreted that product performance shares a direct relationship with brand quality, brand quality, and brand reputation. Result also showed that brand quality and brand equity has a significant effect on product performance, whereas brand reputation has an insignificant effect on product performance.
Abstract: The purpose of this article is to find a method
of comparing designs for ordinal regression models using
quantile dispersion graphs in the presence of linear predictor
misspecification. The true relationship between response variable
and the corresponding control variables are usually unknown.
Experimenter assumes certain form of the linear predictor of the
ordinal regression models. The assumed form of the linear predictor
may not be correct always. Thus, the maximum likelihood estimates
(MLE) of the unknown parameters of the model may be biased due to
misspecification of the linear predictor. In this article, the uncertainty
in the linear predictor is represented by an unknown function. An
algorithm is provided to estimate the unknown function at the
design points where observations are available. The unknown function
is estimated at all points in the design region using multivariate
parametric kriging. The comparison of the designs are based on
a scalar valued function of the mean squared error of prediction
(MSEP) matrix, which incorporates both variance and bias of the
prediction caused by the misspecification in the linear predictor. The
designs are compared using quantile dispersion graphs approach.
The graphs also visually depict the robustness of the designs on the
changes in the parameter values. Numerical examples are presented
to illustrate the proposed methodology.
Abstract: The objective of this study is to analyze the evolution of some social and economic indicators of Mercosur´s economies from 1980 to 2012, based on the statistics of the Latin American Integration Association (LAIA). The objective is to observe if after the accession of these economies to Mercosur (the first accessions occurred in 1994) these indicators showed better performance, in order to demonstrate if economic integration contributed to improved trade, macroeconomic performance, and level of social and economic development of member countries. To this end, the methodologies used will be a literature review and descriptive statistics. The theoretical framework that guides the work are the theories of Integration: Classical Liberal, Marxist and structural-proactive. The results reveal that most social and economic indicators showed better performance in those economies that joined Mercosur after 1994. This work is the result of an investigation already completed.
Abstract: Retinoblastoma is a rare type of childhood genetic cancer that affects children worldwide. The diagnosis is often missed due to lack of education and difficulty in presentation of the tumor. Frequently, the tumor on the retina is noticed by photography when the red-eye flash, commonly seen in normal eyes, is not produced. Instead, a yellow or white colored patch is seen or the child has a noticeable strabismus. Early detection can be life-saving though often results in removal of the affected eye. Remaining functioning in the healthy eye when the child is young has resulted in super-vision and high or above-average intelligence. Technological advancement of cameras has helped in early detection. Brain imaging has also made possible early detection of neurological diseases and, together with the monitoring of cortisol levels and yawning frequency, promises to be the next new early diagnostic tool for the detection of neurological diseases where cortisol insufficiency is particularly salient, such as multiple sclerosis and Cushing’s disease.
Abstract: Since Google launched Google Glass in 2012, numbers of commercial wearable devices were released, such as smart belt, smart band, smart shoes, smart clothes ... etc. However, most of these devices perform as sensors to show the readings of measurements and few of them provide the interactive feedback to the user. Furthermore, these devices are single task devices which are not able to communicate with each other. In this paper a new health promotion system, Ubiquitous Life People Informatics Engine (U-Life PIE), will be presented. This engine consists of People Informatics Engine (PIE) and the interactive user interface. PIE collects all the data from the compatible devices, analyzes this data comprehensively and communicates between devices via various application programming interfaces. All the data and informations are stored on the PIE unit, therefore, the user is able to view the instant and historical data on their mobile devices any time. It also provides the real-time hands-free feedback and instructions through the user interface visually, acoustically and tactilely. These feedback and instructions suggest the user to adjust their posture or habits in order to avoid the physical injuries and prevent illness.
Abstract: South Korea, as the 7th largest greenhouse gas emitting
country in 2011, announced that the national reduction target of
greenhouse gas emissions was 30% based on BAU (Business As
Usual) by 2020. And the reduction rate of the transport sector is 34.3%
which is the highest figure among all sectors. This paper attempts to
analyze the environmental effect on deploying the green cars in
Korean road transport sector. In order to calculate the greenhouse gas
emissions, the LEAP model is applied in this study.
Abstract: Recently, fluidized bed gasification becomes an attractive technology for power generation due to its higher efficiency. The main objective pursued in this work is to investigate the producer gas production potential from sized biomass (sawdust and pigeon pea) by applying the air gasification technique. The size of the biomass selected for the study was in the range of 0.40-0.84 mm. An experimental study was conducted using a fluidized bed gasifier with 210 mm diameter and 1600 mm height. During the experiments, the fuel properties and the effects of operating parameters such as gasification temperatures 700 to 900 °C, equivalence ratio 0.16 to 0.46 were studied. It was concluded that substantial amounts of producer gas (up to 1110 kcal/m3) could be produced utilizing biomass such as sawdust and pigeon pea by applying this fluidization technique. For both samples, the rise of temperature till 900 °C and equivalence ratio of 0.4 favored further gasification reactions and resulted into producer gas with calorific value 1110 kcal/m3.
Abstract: Headache is one of the most ubiquitous and frequent
neurological disorders interfering with everyday life in all countries.
India appears to be no exception. Objectives are to assess the
prevalence of headache among adult population in urban area of
Varanasi and to find out factors influencing the occurrence of
headache. A community based cross sectional study was conducted
among adult population in urban area of Varanasi district, Uttar
Pradesh, India. Total 151 eligible respondents were interviewed by
simple random sampling technique. Proportion percentage and Chisquare
test were applied for data analysis. Out of 151 respondents,
majority (58.3%) were females. In this study, 92.8% respondents
belonged to age group 18-60 years while 7.2% was either 60 year of
age or above. The overall prevalence of headache was found to be
51.1%. Highest and lowest prevalence of headache was recorded in
age groups 18-29 year & 40-49 year respectively. Headache was
62.1% in illiterate and was 40.0% among graduate & above.
Unskilled workers had more headache 73.1% than other type of
occupation. Headache was more prevalent among unemployed
(35.9%) than employed (6.4%). Females had higher family history of
headache (48.9%) as compared to males (41.3%). Study subjects
having peaceful relation with family members, relatives and
neighbors had more headache than those having no peaceful relation.
Abstract: Problems of food security and the preservation of
reserved zones in the region of Central Asia under the conditions of
the climate change induced by the placement and construction of
large reservoirs are considered. The criteria for the optimum
placement and construction of reservoirs that entail the minimum
impact on the environment are established. The need for the
accounting of climatic parameters is shown by the calculation of the
water quantity required for the irrigation of agricultural lands.
Abstract: This paper takes a philosophical view as axiom, and
reveals the relationship between information theory and Natural
Intelligence and Artificial Intelligence under real world conditions.
This paper also derives the relationship between natural intelligence
and nature. According to communication principle of information
theory, Natural Intelligence can be divided into real part and virtual
part. Based on information theory principle that Information does not
increase, the restriction mechanism of Natural Intelligence creativity is
conducted. The restriction mechanism of creativity reveals the limit of
natural intelligence and artificial intelligence. The paper provides a
new angle to observe natural intelligence and artificial intelligence.
Abstract: In nearly all earthquakes of the past century that
resulted in moderate to significant damage, the occurrence of postearthquake
fire ignition (PEFI) has imposed a serious hazard and
caused severe damage, especially in urban areas. In order to reduce
the loss of life and property caused by post-earthquake fires, there is
a crucial need for predictive models to estimate the PEFI risk. The
parameters affecting PEFI risk can be categorized as: 1) factors
influencing fire ignition in normal (non-earthquake) condition,
including floor area, building category, ignitability, type of appliance,
and prevention devices, and 2) earthquake related factors contributing
to the PEFI risk, including building vulnerability and earthquake
characteristics such as intensity, peak ground acceleration, and peak
ground velocity. State-of-the-art statistical PEFI risk models are
solely based on limited available earthquake data, and therefore they
cannot predict the PEFI risk for areas with insufficient earthquake
records since such records are needed in estimating the PEFI model
parameters. In this paper, the correlation between normal condition
ignition risk, peak ground acceleration, and PEFI risk is examined in
an effort to offer a means for predicting post-earthquake ignition
events. An illustrative example is presented to demonstrate how such
correlation can be employed in a seismic area to predict PEFI hazard.
Abstract: During an earthquake, a bridge crane may be
subjected to multiple impacts between crane wheels and rail. In order
to model such phenomena, a time-history dynamic analysis with a
multi-scale approach is performed. The high frequency aspect of the
impacts between wheels and rails is taken into account by a Lagrange
explicit event-capturing algorithm based on a velocity-impulse
formulation to resolve contacts and impacts. An implicit temporal
scheme is used for the rest of the structure. The numerical coupling
between the implicit and the explicit schemes is achieved with a
heterogeneous asynchronous time-integrator.
Abstract: Classification is an important data mining technique
and could be used as data filtering in artificial intelligence. The
broad application of classification for all kind of data leads to be
used in nearly every field of our modern life. Classification helps us
to put together different items according to the feature items decided
as interesting and useful. In this paper, we compare two
classification methods Naïve Bayes and ADTree use to detect spam
e-mail. This choice is motivated by the fact that Naive Bayes
algorithm is based on probability calculus while ADTree algorithm is
based on decision tree. The parameter settings of the above
classifiers use the maximization of true positive rate and
minimization of false positive rate. The experiment results present
classification accuracy and cost analysis in view of optimal classifier
choice for Spam Detection. It is point out the number of attributes to
obtain a tradeoff between number of them and the classification
accuracy.
Abstract: This study was designed to evaluate whether carvacrol
(CAR) could provide protection against lung injury by acute
pancreatitis development. The rats were randomized into groups to
receive (I) no therapy; (II) 50 μg/kg cerulein at 1h intervals by four
intraperitoneal injections (i.p.); (III) 50, 100 and 200 mg/kg CAR by
one i.p.; and (IV) cerulein+CAR after 2h of cerulein injection. 12h
later, serum samples were obtained to assess pancreatic function the
lipase and amylase values. The animals were euthanized and lung
samples were excised. The specimens were stained with
hematoxylin-eosin (H&E), periodic acid–Schif (PAS), Mallory's
trichrome and amyloid. Additionally, oxidative DNA damage was
determined by measuring as increases in 8-hydroxy-deoxyguanosine
(8-OH-dG) adducts. The results showed that the serum activity of
lipase and amylase in AP rats were significantly reduced after the
therapy (p
Abstract: An approach to compute optimum seismic design parameters is presented. It is based on the optimization of the expected present value of the total cost, which includes the initial cost of structures as well as the cost due to earthquakes. Different types of seismicity models are considered, including one for characteristic earthquakes. Uncertainties are included in some variables to observe the influence on optimum values. Optimum seismic design coefficients are computed for three different structural types representing high, medium and low rise buildings, located near and far from the seismic sources. Ordinary and important structures are considered in the analysis. The results of optimum values show an important influence of seismicity models as well as of uncertainties on the variables.