Abstract: The tribological outcomes of micro dent are found to be outstanding in many engineering and natural surfaces. Ceramic (Al2O3) is considered one of the most potential material to bearing surfaces particularly, artificial hip or knee implant. A well-defined micro dent on alumina oxide interface could further decrease friction and wear rate, thus increase their stability and durability. In this study we fabricated circular micro dent surface profiles (Dia: 400µm, Depth 20µm, P: 1.5mm; Dia: 400µm, Depth 20µm, P: 2mm) on pure Al2O3 (99.6%) substrate by using a micro tool machines. A preliminary tribological experiment was carried out to compare friction coefficient of these fabricated dent surfaces with that of non-textured surfaces. The experiment was carried on well know pin-on-disk specimens while other experimental parameters such as hertz pressure, speed, lubrication, and temperature were maintained to standard of simulated hip joints condition. The experiment results revealed that micro dent surface texture reduced 15%, 8% and 4% friction coefficient under 0.132,0.162, 0.187 GPa contact pressure respectively. Since this is a preliminary tribological study, we will pursue further experiments considering higher ranges of dent profiles and longer run experiments. However, the preliminary results confirmed the suitability of fabricating dent profile to ceramic surfaces by using micro tooling, and also their improved tribological performance in simulated hip joints.
Abstract: The transfer rate of messages in distributed sensor network applications is a critical factor in a system's performance. The Sensor Abstraction Layer (SAL) is one such system. SAL is a middleware integration platform for abstracting sensor specific technology in order to integrate heterogeneous types of sensors in a network. SAL uses Java Remote Method Invocation (RMI) as its connection method, which has unsatisfying transfer rates, especially for streaming data. This paper analyses different connection methods to optimize data transmission in SAL by replacing RMI. Our results show that the most promising Java-based connections were frameworks for Java New Input/Output (NIO) including Apache MINA, JBoss Netty, and xSocket. A test environment was implemented to evaluate each respective framework based on transfer rate, resource usage, and scalability. Test results showed the most suitable connection method to improve data transmission in SAL JBoss Netty as it provides a performance enhancement of 68%.
Abstract: We introduced the notions of (1, k)-prime ideal and (1, k)-jointly prime (R, S)-submodule as a generalization of prime ideal and jointly prime (R, S)-submodule, respectively. We provide a relationship between (1, k)-prime ideal and (1, k)-jointly prime (R, S)-submodule. Characterizations of (1, k)-jointly prime (R, S)- submodules are also given.
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: The use of a conventional air plasma-sprayed thermal barrier coating (TBC) and a porous, functionally graded TBC as a thermal insulator for Al7075 alloy was explored. A quench test at 1200°C employing fast heating and cooling rates was setup to represent a dynamic thermal condition of an aerospace component. During the test, coated samples were subjected the ambient temperature of 1200°C for a very short time. This was followed by a rapid drop in temperature resulting in cracking of the coatings. For the conventional TBC, it was found that the temperature of the Al7075 substrate decreases with the increase in the ZrO2 topcoat thickness. However, at the topcoat thickness of 1100 µm, large horizontal cracks can be observed in the topcoat and at the topcoat thickness of 1600 µm, the topcoat delaminate during cooling after the quench test. The porous, functionally graded TBC with 600 µm thick topcoat, on the other hand, was found to be as effective at reducing the substrate temperature as the conventional TBC with 1100 µm thick topcoat. The maximum substrate temperature is about 213°C for the former and 208°C for the latter when a heating rate of 38°C/s was used. When the quench tests were conducted with a faster heating rate of 128°C/s, the Al7075 substrate heat up faster with a reduction in the maximum substrate temperatures. The substrate temperatures dropped from 297 to 212°C for the conventional TBC and from 213 to 155°C for the porous TBC, both with 600 µm thick topcoat. Segmentation cracks were observed in both coating after the quench test.
Abstract: Discrete wavelet transform (DWT) has been widely adopted in biomedical signal processing for denoising, compression
and so on. Choosing a suitable decomposition level (DL) in DWT is of paramount importance to its performance. In this paper, we propose to exploit sparseness of the transformed signals to determine the appropriate DL. Simulation results have shown that the sparseness of transformed signals after DWT increases with the increasing DLs. Additional Monte-Carlo simulation results have verified the effectiveness of sparseness measure in determining the DL.
Abstract: The objective of this study is to investigate the performance of the electrocoagulation process for color and COD removal in palm oil wastewater using a 10 L batch reactor. Iron was used as electrodes and the distance between electrodes was 2 cm. The effects of operating parameters: current voltage (6, 12 and 18 volt), reaction time (5, 15, 30, 45 and 60 min) and initial pH (4 and 9) of treatment efficiency were examine. The result showed that decolorization and COD removal efficiency increased with the increase in current voltage and reaction time. The proper condition for decolorization achieved at initial pH 4 and 9 were current voltage of 12 volt, reaction time 30 min. The decolorization efficiency reached 90.4% and 88.9%, respectively. COD removal was achiveved at current voltage 12 volt, reaction time 15 min. COD removal efficiency was 89.2 % and 83.0%, respectively. From the results, to show electrocoagulation process can treat palm oil mill wastewater in both acidic and basic condition at high efficiency for color and COD removal. Consequently, electrocoagulation process can be used or applied as a post-treatment step to improve the quality of the final discharge in term of color and residual COD removal.
Abstract: The purpose of the research is to investigate the energetic feature of the backpack load on soldier’s gait with variation of the trunk flexion angle. It is believed that the trunk flexion variation of the loaded gait may cause a significant difference in the energy cost which is often in practice in daily life. To this end, seven healthy Korea military personnel participated in the experiment and are tested under three different walking postures comprised of the small, natural and large trunk flexion. There are around 5 degree differences of waist angle between each trunk flexion. The ground reaction forces were collected from the force plates and motion kinematic data are measured by the motion capture system. Based on these data, the impulses, momentums and mechanical works done on the center of body mass (COM) during the double support phase were computed. The result shows that the push-off and heel strike impulse are not relevant to the trunk flexion change, however the mechanical work by the push-off and heel strike were changed by the trunk flexion variation. It is because the vertical velocity of the COM during the double support phase is increased significantly with an increase in the trunk flexion. Therefore, we can know that the gait efficiency of the loaded gait depends on the trunk flexion angle. Also, even though the gravitational impulse and pre-collision momentum are changed by the trunk flexion variation, the after-collision momentum is almost constant regardless of the trunk flexion variation.
Abstract: The exponential increase in the volume of medical image database has imposed new challenges to clinical routine in maintaining patient history, diagnosis, treatment and monitoring. With the advent of data mining and machine learning techniques it is possible to automate and/or assist physicians in clinical diagnosis. In this research a medical image classification framework using data mining techniques is proposed. It involves feature extraction, feature selection, feature discretization and classification. In the classification phase, the performance of the traditional kNN k nearest neighbor classifier is improved using a feature weighting scheme and a distance weighted voting instead of simple majority voting. Feature weights are calculated using the interestingness measures used in association rule mining. Experiments on the retinal fundus images show that the proposed framework improves the classification accuracy of traditional kNN from 78.57 % to 92.85 %.
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: The problem of optimal planning of multiple sources
of distributed generation (DG) in distribution networks is treated in
this paper using an improved Ant Colony Optimization algorithm
(ACO). This objective of this problem is to determine the DG
optimal size and location that in order to minimize the network real
power losses. Considering the multiple sources of DG, both size and
location are simultaneously optimized in a single run of the proposed
ACO algorithm. The various practical constraints of the problem are
taken into consideration by the problem formulation and the
algorithm implementation. A radial power flow algorithm for
distribution networks is adopted and applied to satisfy these
constraints. To validate the proposed technique and demonstrate its
effectiveness, the well-know 69-bus feeder standard test system is
employed.cm.
Abstract: The influence of copper and zinc supplements on milk
production performances and health indicators was tested in a 20-
week feeding trial, with 40 Holstein-Friesian lactating cows, devided
in four groups (copper, zinc, copper-zinc and control). Correlations of
the Cu and Zn plasma values with some animal performance criteria
of health (body condition score and somatic cell counts) and
production (milk yield, peak milk yield, fat and crude protein
content) were done. During the 140 days of the experiment, the two
added minerals caused a statistically significant increase (p < 0.05) of
their plasma values after the peak of the cows’ lactations. It was also
observed that subjects that have received copper and zinc
supplements had the lowest number of somatic cell counts in milk.
The Pearson correlation test showed a positive corellation (p = 0.007,
r = + 0.851) between the plasma Zn and the milk production. The
improvement of the nutritional status improved the milk production
performances of the cows as well as their health performances.
Abstract: Building a service-centric business model requires
new knowledge and capabilities in companies. This paper enlightens
the challenges small and medium sized firms (SMEs) face when
developing their service-centric business models. This paper
examines the premise for knowledge transfer and capability
development required. The objective of this paper is to increase
knowledge about SME-s transformation to service-centric business
models.This paper reports an action research based case study. The
paper provides empirical evidence from three case companies. The
empirical data was collected through multiple methods. The findings
of the paper are: First, the developed model to analyze the current
state in companies. Second, the process of building the service –
centric business models. Third, the selection of suitable service
development methods. The lack of a holistic understanding on
service logic suggests that SMEs need practical and easy to use
methods to improve their business
Abstract: Papaya and banana bars were developed incorporating
inulin (IN) and fructooligosaccharides (FOS) (Liquid and Powder
form) in various proportions. The control bars were standardized
using 70% fruit pulp, 30% sugar, 0.3% citric acid while the treated
bars were standardized with 70% fruit pulp, 15% sugar, 15% of IN
and FOS and 0.3% citric acid. Among the various proportions tested,
papaya bars with 90% FOS (Powder) + 10% IN and banana bars with
90% FOS (liquid) + 10% IN were sensorially best accepted. The
study revealed that addition of IN and FOS improved the sensory
scores. The Physico-chemical and proximatecomposition analysis
revealed slight changes in brix°, total sugars, reducing sugars, nonreducing
sugars, moisture, protein, fat, vitamin C, ash, iron,
zinc, calcium and crude fibre between control and treated fruit bars.
Further the glycemic index of papaya bar was reduced from 65 to 54
when treated with FOS and IN.
Abstract: In this paper, backstepping method (BM) is proposed for a single-link flexible mechanical manipulator. In each step of this method a positive value is obtained. Selections of the gain factor values are very important because controller will have different behavior for each different set of values. Improper selection of these gains can lead to instability of the system. In order to choose proper values for gains BELBIC method has been used in this work. Finally, to prove the efficiency of this method, the obtained results of proposed model are compared with robust controller one. Results show that the combination of backstepping and BELBIC that is presented here, can stabilized the system with higher speed, shorter settling time and lower overshoot in than robust controller.
Abstract: This paper presents a customized deformable model
for the segmentation of abdominal and thoracic aortic aneurysms in
CTA datasets. An important challenge in reliably detecting aortic
aneurysm is the need to overcome problems associated with intensity
inhomogeneities and image noise. Level sets are part of an important
class of methods that utilize partial differential equations (PDEs) and
have been extensively applied in image segmentation. A Gaussian
kernel function in the level set formulation, which extracts the local
intensity information, aids the suppression of noise in the extracted
regions of interest and then guides the motion of the evolving contour
for the detection of weak boundaries. The speed of curve evolution
has been significantly improved with a resulting decrease in
segmentation time compared with previous implementations of level
sets. The results indicate the method is more effective than other
approaches in coping with intensity inhomogeneities.
Abstract: Thermite welding is mainly used in world. The
reasons why the thermite welding method is widely used are
that the equipment has good mobility and total working time
of that is shorter than that of the enclosed arc welding method
on site. Moreover, the operating skill, which required for
thermite welding, is less than that of for enclosed arc welding.
In the present research work, heat treatment and combined
'expulsion and heat treatment' techniques were used improve
the mechanical properties and weldment structure. The
specimens were cut in the transverse direction from expulsion
with Heat treated and heat treated Thermite Welded rails.
Specimens were prepared according to AWS standard and
subjected to tensile test, Impact test and hardness and their
results were tabulated. Microstructural analysis was carried
out with the help of SEM. Then analyze to effect of heat
treated and 'expulsion with heat treated' with the properties of
their thermite welded rails. Compare the mechanical and
microstructural properties of thermite welded rails between
heat expulsion with heat treated and heat treated. Mechanical
and microstructural response expulsion with heat treated
thermite welded rail is higher value as compared to heat
treatment.
Abstract: For the improvement of the ability in detecting
small calcifications using Ultrasonography (US) we propose a
novel indicator of calcifications in an ultrasound B-mode image
without decrease in frame rate. Since the waveform of an
ultrasound pulse changes at a calcification position, the
decorrelation of adjacent scan lines occurs behind a
calcification. Therefore, we employ the decorrelation of
adjacent scan lines as an indicator of a calcification. The
proposed indicator depicted wires 0.05 mm in diameter at 2 cm
depth with a sensitivity of 86.7% and a specificity of 100%,
which were hardly detected in ultrasound B-mode images. This
study shows the potential of the proposed indicator to
approximate the detectable calcification size using an US
device to that of an X-ray imager, implying the possibility that
an US device will become a convenient, safe, and principal
clinical tool for the screening of breast cancer.
Abstract: In this paper a comprehensive algorithm is presented to alleviate the undesired simultaneous effects of target maneuvering, observed glint noise distribution, and colored noise spectrum using online colored glint noise parameter estimation. The simulation results illustrate a significant reduction in the root mean square error (RMSE) produced by the proposed algorithm compared to the algorithms that do not compensate all the above effects simultaneously.
Abstract: Steganography is the process of hiding one file inside another such that others can neither identify the meaning of the embedded object, nor even recognize its existence. Current trends favor using digital image files as the cover file to hide another digital file that contains the secret message or information. One of the most common methods of implementation is Least Significant Bit Insertion, in which the least significant bit of every byte is altered to form the bit-string representing the embedded file. Altering the LSB will only cause minor changes in color, and thus is usually not noticeable to the human eye. While this technique works well for 24-bit color image files, steganography has not been as successful when using an 8-bit color image file, due to limitations in color variations and the use of a colormap. This paper presents the results of research investigating the combination of image compression and steganography. The technique developed starts with a 24-bit color bitmap file, then compresses the file by organizing and optimizing an 8-bit colormap. After the process of compression, a text message is hidden in the final, compressed image. Results indicate that the final technique has potential of being useful in the steganographic world.