Search results for: m/chip advance standard
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5824

Search results for: m/chip advance standard

4774 Effect of Zirconium (Zr) Amount on Mechanical and Metallurgical Behavior of ZE41A Magnesium Alloy

Authors: Emrah Yaliniz, Ali Kalkanli

Abstract:

ZE41A magnesium alloy has been extensively used in aerospace industry, especially for use in rotorcraft transmission casings. Due to the improved mechanical properties, the latest generation of magnesium casting alloy EV31A-T6 (Elektron 21® specified in AMS 4429) is seen as a potential replacement for ZE41A in terms of strength. Therefore, the necessity of enhancement has been arisen for ZE41A in order to avoid fully replacement. The main element affecting the strength of ZE41A is Zirconium (Zr), which acts as a grain refiner. The specified range of Zr element for ZE41A alloy is between 0.4 wt % and 1.0 wt % (unless otherwise stated by weight percentage after this point) as stated in AMS 4439. This paper investigates the effects of Zr amount on tensile and metallurgical properties of ZE41A magnesium alloy. The Zr alloying amount for the research has been chosen as 0.5 % and 1 %, which are standard amounts in a commercial alloy (average of 0.4-0.6%) and maximum percent in the standard, separately. 1 % Zr amount has been achieved via Zirmax (66.7 Mg-33.3 Zr) master alloy addition. The ultimate tensile strength of ZE41A with 1% Zr has been increased up to about 220-225 MPa in comparison to 200 MPa given in AMS 4439. The reason for the increase in strength with the addition of Zirmax is based on the decrease in grain size, which was measured about 30 µm. Optical microscope, scanning electron microscopy (SEM) and X-ray Diffraction (XRD) were used to detect the change in the microstructural futures via alloying. The zirconium rich coring at the center of the grains was observed in addition to the grain boundary intermetallic phases and bulk Mg-rich matrix. The solidification characteristics were also identified by using the cooling curve obtained from the sand casting mold during cooling of the alloys.

Keywords: aerospace, grain refinement, magnesium, sand casting, ZE41A

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4773 Evaluating the Influence of Financial Technology (FinTech) on Sustainable Finance: A Comprehensive Global Analysis

Authors: Muhammad Kashif

Abstract:

The primary aim of this paper is to investigate the influence of financial technology (FinTech) on sustainable finance. The sample for this study spans from 2010 to 2021, encompassing data from 89 countries worldwide. The study employed two-stage least squares (2SLS) regression approach with the instrumental variables and validated the findings using a two-step system generalized method of moments (GMM). The findings indicate that fintech has a significant favorable impact on sustainable finance. While other factors such as institutional quality, socio-economic condition, and renewable energy have a significant and beneficial influence on the trajectory of sustainable finance, except globalization's impact is positive but insignificant. Furthermore, fintech is crucial in driving the transition toward a sustainable future characterized by a lower carbon economy. The study found that fintech has extensive application across various sectors of sustainable finance and has substantial potential to create long-term positive effects on sustainable finance. Fintech can integrate extensively with other technologies to facilitate diversified growth in sustainable finance. Additionally, this study highlights fintech-related trends and research opportunities in sustainable finance, showing how these can promote each other worldwide with important policy implications for countries looking to advance sustainable finance through technology.

Keywords: sustainable development goals (SDGs), financial technology (FinTech), genuine savings index (GSI), financial stability index, sustainable finance

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4772 Comparing Xbar Charts: Conventional versus Reweighted Robust Estimation Methods for Univariate Data Sets

Authors: Ece Cigdem Mutlu, Burak Alakent

Abstract:

Maintaining the quality of manufactured products at a desired level depends on the stability of process dispersion and location parameters and detection of perturbations in these parameters as promptly as possible. Shewhart control chart is the most widely used technique in statistical process monitoring to monitor the quality of products and control process mean and variability. In the application of Xbar control charts, sample standard deviation and sample mean are known to be the most efficient conventional estimators in determining process dispersion and location parameters, respectively, based on the assumption of independent and normally distributed datasets. On the other hand, there is no guarantee that the real-world data would be normally distributed. In the cases of estimated process parameters from Phase I data clouded with outliers, efficiency of traditional estimators is significantly reduced, and performance of Xbar charts are undesirably low, e.g. occasional outliers in the rational subgroups in Phase I data set may considerably affect the sample mean and standard deviation, resulting a serious delay in detection of inferior products in Phase II. For more efficient application of control charts, it is required to use robust estimators against contaminations, which may exist in Phase I. In the current study, we present a simple approach to construct robust Xbar control charts using average distance to the median, Qn-estimator of scale, M-estimator of scale with logistic psi-function in the estimation of process dispersion parameter, and Harrell-Davis qth quantile estimator, Hodge-Lehmann estimator and M-estimator of location with Huber psi-function and logistic psi-function in the estimation of process location parameter. Phase I efficiency of proposed estimators and Phase II performance of Xbar charts constructed from these estimators are compared with the conventional mean and standard deviation statistics both under normality and against diffuse-localized and symmetric-asymmetric contaminations using 50,000 Monte Carlo simulations on MATLAB. Consequently, it is found that robust estimators yield parameter estimates with higher efficiency against all types of contaminations, and Xbar charts constructed using robust estimators have higher power in detecting disturbances, compared to conventional methods. Additionally, utilizing individuals charts to screen outlier subgroups and employing different combination of dispersion and location estimators on subgroups and individual observations are found to improve the performance of Xbar charts.

Keywords: average run length, M-estimators, quality control, robust estimators

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4771 Reconstruction Spectral Reflectance Cube Based on Artificial Neural Network for Multispectral Imaging System

Authors: Iwan Cony Setiadi, Aulia M. T. Nasution

Abstract:

The multispectral imaging (MSI) technique has been used for skin analysis, especially for distant mapping of in-vivo skin chromophores by analyzing spectral data at each reflected image pixel. For ergonomic purpose, our multispectral imaging system is decomposed in two parts: a light source compartment based on LED with 11 different wavelenghts and a monochromatic 8-Bit CCD camera with C-Mount Objective Lens. The software based on GUI MATLAB to control the system was also developed. Our system provides 11 monoband images and is coupled with a software reconstructing hyperspectral cubes from these multispectral images. In this paper, we proposed a new method to build a hyperspectral reflectance cube based on artificial neural network algorithm. After preliminary corrections, a neural network is trained using the 32 natural color from X-Rite Color Checker Passport. The learning procedure involves acquisition, by a spectrophotometer. This neural network is then used to retrieve a megapixel multispectral cube between 380 and 880 nm with a 5 nm resolution from a low-spectral-resolution multispectral acquisition. As hyperspectral cubes contain spectra for each pixel; comparison should be done between the theoretical values from the spectrophotometer and the reconstructed spectrum. To evaluate the performance of reconstruction, we used the Goodness of Fit Coefficient (GFC) and Root Mean Squared Error (RMSE). To validate reconstruction, the set of 8 colour patches reconstructed by our MSI system and the one recorded by the spectrophotometer were compared. The average GFC was 0.9990 (standard deviation = 0.0010) and the average RMSE is 0.2167 (standard deviation = 0.064).

Keywords: multispectral imaging, reflectance cube, spectral reconstruction, artificial neural network

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4770 A Validated High-Performance Liquid Chromatography-UV Method for Determination of Malondialdehyde-Application to Study in Chronic Ciprofloxacin Treated Rats

Authors: Anil P. Dewani, Ravindra L. Bakal, Anil V. Chandewar

Abstract:

Present work demonstrates the applicability of high-performance liquid chromatography (HPLC) with UV detection for the determination of malondialdehyde as malondialdehyde-thiobarbituric acid complex (MDA-TBA) in-vivo in rats. The HPLC-UV method for MDA-TBA was achieved by isocratic mode on a reverse-phase C18 column (250mm×4.6mm) at a flow rate of 1.0mLmin−1 followed by UV detection at 278 nm. The chromatographic conditions were optimized by varying the concentration and pH followed by changes in percentage of organic phase optimal mobile phase consisted of mixture of water (0.2% Triethylamine pH adjusted to 2.3 by ortho-phosphoric acid) and acetonitrile in ratio (80:20 % v/v). The retention time of MDA-TBA complex was 3.7 min. The developed method was sensitive as limit of detection and quantification (LOD and LOQ) for MDA-TBA complex were (standard deviation and slope of calibration curve) 110 ng/ml and 363 ng/ml respectively. The method was linear for MDA spiked in plasma and subjected to derivatization at concentrations ranging from 100 to 1000 ng/ml. The precision of developed method measured in terms of relative standard deviations for intra-day and inter-day studies was 1.6–5.0% and 1.9–3.6% respectively. The HPLC method was applied for monitoring MDA levels in rats subjected to chronic treatment of ciprofloxacin (CFL) (5mg/kg/day) for 21 days. Results were compared by findings in control group rats. Mean peak areas of both study groups was subjected for statistical treatment to unpaired student t-test to find p-values. The p value was < 0.001 indicating significant results and suggesting increased MDA levels in rats subjected to chronic treatment of CFL of 21 days.

Keywords: MDA, TBA, ciprofloxacin, HPLC-UV

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4769 Effects of Probiotic Pseudomonas fluorescens on the Growth Performance, Immune Modulation, and Histopathology of African Catfish (Clarias gariepinus)

Authors: Nelson R. Osungbemiro, O. A. Bello-Olusoji, M. Oladipupo

Abstract:

This study was carried out to determine the effects of probiotics Pseudomonas fluorescens on the growth performance, histology examination and immune modulation of African Catfish, (Clarias gariepinus) challenged with Clostridium botulinum. P. fluorescens, and C. botulinum isolates were removed from the gut, gill and skin organs of procured adult samples of Clarias gariepinus from commercial fish farms in Akure, Ondo State, Nigeria. The physical and biochemical tests were performed on the bacterial isolates using standard microbiological techniques for their identification. Antibacterial activity tests on P. fluorescens showed inhibition zone with mean value of 3.7 mm which indicates high level of antagonism. The experimental diets were prepared at different probiotics bacterial concentration comprises of five treatments of different bacterial suspension, including the control (T1), T2 (10³), T3 (10⁵), T4 (10⁷) and T5 (10⁹). Three replicates for each treatment type were prepared. Growth performance and nutrients utilization indices were calculated. The proximate analysis of fish carcass and experimental diet was carried out using standard methods. After feeding for 70 days, haematological values and histological test were done following standard methods; also a subgroup from each experimental treatment was challenged by inoculating Intraperitonieally (I/P) with different concentration of pathogenic C. botulinum. Statistically, there were significant differences (P < 0.05) in the growth performance and nutrient utilization of C. gariepinus. Best weight gain and feed conversion ratio were recorded in fish fed T4 (10⁷) and poorest value obtained in the control. Haematological analyses of C. gariepinus fed the experimental diets indicated that all the fish fed diets with P. fluorescens had marked significantly (p < 0.05) higher White Blood Cell than the control diet. The results of the challenge test showed that fish fed the control diet had the highest mortality rate. Histological examination of the gill, intestine, and liver of fish in this study showed several histopathological alterations in fish fed the control diets compared with those fed the P. fluorescens diets. The study indicated that the optimum level of P. fluorescens required for C. gariepinus growth and white blood cells formation is 10⁷ CFU g⁻¹, while carcass protein deposition required 10⁵ CFU g⁻¹ of P. fluorescens concentration. The study also confirmed P. fluorescens as efficient probiotics that is capable of improving the immune response of C. gariepinus against the attack of a virulent fish pathogen, C. botulinum.

Keywords: Clarias gariepinus, Clostridium botulinum, probiotics, Pseudomonas fluorescens

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4768 Operative Tips of Strattice Based Breast Reconstruction

Authors: Cho Ee Ng, Hazem Khout, Tarannum Fasih

Abstract:

Acellular dermal matrices are increasingly used to reinforce the lower pole of the breast during implant breast reconstruction. There is no standard technique described in literature for the use of this product. In this article, we share our operative method of fixation.

Keywords: strattice, acellular dermal matric, breast reconstruction, implant

Procedia PDF Downloads 394
4767 Effective Dose and Size Specific Dose Estimation with and without Tube Current Modulation for Thoracic Computed Tomography Examinations: A Phantom Study

Authors: S. Gharbi, S. Labidi, M. Mars, M. Chelli, F. Ladeb

Abstract:

The purpose of this study is to reduce radiation dose for chest CT examination by including Tube Current Modulation (TCM) to a standard CT protocol. A scan of an anthropomorphic male Alderson phantom was performed on a 128-slice scanner. The estimation of effective dose (ED) in both scans with and without mAs modulation was done via multiplication of Dose Length Product (DLP) to a conversion factor. Results were compared to those measured with a CT-Expo software. The size specific dose estimation (SSDE) values were obtained by multiplication of the volume CT dose index (CTDIvol) with a conversion size factor related to the phantom’s effective diameter. Objective assessment of image quality was performed with Signal to Noise Ratio (SNR) measurements in phantom. SPSS software was used for data analysis. Results showed including CARE Dose 4D; ED was lowered by 48.35% and 51.51% using DLP and CT-expo, respectively. In addition, ED ranges between 7.01 mSv and 6.6 mSv in case of standard protocol, while it ranges between 3.62 mSv and 3.2 mSv with TCM. Similar results are found for SSDE; dose was higher without TCM of 16.25 mGy and was lower by 48.8% including TCM. The SNR values calculated were significantly different (p=0.03<0.05). The highest one is measured on images acquired with TCM and reconstructed with Filtered back projection (FBP). In conclusion, this study proves the potential of TCM technique in SSDE and ED reduction and in conserving image quality with high diagnostic reference level for thoracic CT examinations.

Keywords: anthropomorphic phantom, computed tomography, CT-expo, radiation dose

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4766 A Practice Model for Quality Improvement in Concrete Block Mini Plants Based on Merapi Volcanic Sand

Authors: Setya Winarno

Abstract:

Due to abundant Merapi volcanic sand in Yogyakarta City, many local people have utilized it for mass production of concrete blocks through mini plants although their products are low in quality. This paper presents a practice model for quality improvement in this situation in order to supply the current customer interest in good quality of construction material. The method of this research was to investigate a techno economic evaluation through laboratory test and interview. Samples of twenty existing concrete blocks made by local people had only 19.4 kg/cm2 in average compression strength which was lower than the minimum Indonesian standard of 25 kg/cm2. Through repeat testing in laboratory for fulfilling the standard, the concrete mix design of water cement ratio should not be more than 0.64 by weight basis. The proportion of sand as aggregate content should not be more than 9 parts to 1 part by volume of Portland cement. Considering the production cost, the basic price was Rp 1,820 for each concrete block, comparing to Rp 2,000 as a normal competitive market price. At last, the model describes (a) maximum water cement ratio is 0.64, (b) maximum proportion of sand and cement is 1:9, (c) the basic price is about Rp. 1,820.00 and (d) strategies to win the competitive market on mass production of concrete blocks are focus in quality, building relationships with consumer, rapid respond to customer need, continuous innovation by product diversification, promotion in social media, and strict financial management.

Keywords: concrete block, good quality, improvement model, diversification

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4765 American Slang: Perception and Connotations – Issues of Translation

Authors: Lison Carlier

Abstract:

The English language that is taught in school or used in media nowadays is defined as 'standard English,' although unstandardized Englishes, or 'parallel' Englishes, are practiced throughout the world. The existence of these 'parallel' Englishes has challenged standardization by imposing its own specific vocabulary or grammar. These non-standard languages tend to be regarded as inferior and, therefore, pose a problem regarding their translation. In the USA, 'slanguage', or slang, is a good example of a 'parallel' language. It consists of a particular set of vocabulary, used mostly in speech, and rarely in writing. Qualified as vulgar, often reduced to an urban language spoken by young people from lower classes, slanguage – or the language that is often first spoken between youths – is still the most common language used in the English-speaking world. Moreover, it appears that the prime meaning of 'informal' (as in an informal language) – a language that is spoken with persons the speaker knows – has been put aside and replaced in the general mind by the idea of vulgarity and non-appropriateness, when in fact informality is a sign of intimacy, not of vulgarity. When it comes to translating American slang, the main problem a translator encounters is the image and the cultural background usually associated with this 'parallel' language. Indeed, one will have, unwillingly, a predisposition to categorize a speaker of a 'parallel' language as being part of a particular group of people. The way one sees a speaker using it is paramount, and needs to be transposed into the target language. This paper will conduct an analysis of American slang – its use, perception and the image it gives of its speakers – and its translation into French, using the novel Is Everyone Hanging Out Without Me? (and other concerns) by way of example. In her autobiography/personal essay book, comedy writer, actress and author Mindy Kaling speaks with a very familiar English, including slang, which participates in the construction of her own voice and style, and enables a deeper connection with her readers.

Keywords: translation, English, slang, French

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4764 Adaptation of Hough Transform Algorithm for Text Document Skew Angle Detection

Authors: Kayode A. Olaniyi, Olabanji F. Omotoye, Adeola A. Ogunleye

Abstract:

The skew detection and correction form an important part of digital document analysis. This is because uncompensated skew can deteriorate document features and can complicate further document image processing steps. Efficient text document analysis and digitization can rarely be achieved when a document is skewed even at a small angle. Once the documents have been digitized through the scanning system and binarization also achieved, document skew correction is required before further image analysis. Research efforts have been put in this area with algorithms developed to eliminate document skew. Skew angle correction algorithms can be compared based on performance criteria. Most important performance criteria are accuracy of skew angle detection, range of skew angle for detection, speed of processing the image, computational complexity and consequently memory space used. The standard Hough Transform has successfully been implemented for text documentation skew angle estimation application. However, the standard Hough Transform algorithm level of accuracy depends largely on how much fine the step size for the angle used. This consequently consumes more time and memory space for increase accuracy and, especially where number of pixels is considerable large. Whenever the Hough transform is used, there is always a tradeoff between accuracy and speed. So a more efficient solution is needed that optimizes space as well as time. In this paper, an improved Hough transform (HT) technique that optimizes space as well as time to robustly detect document skew is presented. The modified algorithm of Hough Transform presents solution to the contradiction between the memory space, running time and accuracy. Our algorithm starts with the first step of angle estimation accurate up to zero decimal place using the standard Hough Transform algorithm achieving minimal running time and space but lacks relative accuracy. Then to increase accuracy, suppose estimated angle found using the basic Hough algorithm is x degree, we then run again basic algorithm from range between ±x degrees with accuracy of one decimal place. Same process is iterated till level of desired accuracy is achieved. The procedure of our skew estimation and correction algorithm of text images is implemented using MATLAB. The memory space estimation and process time are also tabulated with skew angle assumption of within 00 and 450. The simulation results which is demonstrated in Matlab show the high performance of our algorithms with less computational time and memory space used in detecting document skew for a variety of documents with different levels of complexity.

Keywords: hough-transform, skew-detection, skew-angle, skew-correction, text-document

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4763 Integrated Geotechnical and Geophysical Investigation of a Proposed Construction Site at Mowe, Southwestern Nigeria

Authors: Kayode Festus Oyedele, Sunday Oladele, Adaora Chibundu Nduka

Abstract:

The subsurface of a proposed site for building development in Mowe, Nigeria, using Standard Penetration Test (SPT) and Cone Penetrometer Test (CPT) supplemented with Horizontal Electrical Profiling (HEP) was investigated with the aim of evaluating the suitability of the strata for foundation materials. Four SPT and CPT were implemented using 10 tonnes hammer. HEP utilizing Wenner array were performed with inter-electrode spacing of 10 – 60 m along four traverses coincident with each of the SPT and CPT. The HEP data were processed using DIPRO software and textural filtering of the resulting resistivity sections was implemented to enable delineation of hidden layers. Sandy lateritic clay, silty lateritic clay, clay, clayey sand and sand horizons were delineated. The SPT “N” value defined very soft to soft sandy lateritic (<4), stiff silty lateritic clay (7 – 12), very stiff silty clay (12 - 15), clayey sand (15- 20) and sand (27 – 37). Sandy lateritic clay (5-40 kg/cm2) and silty lateritic clay (25 - 65 kg/cm2) were defined from the CPT response. Sandy lateritic clay (220-750 Ωm), clay (< 50 Ωm) and sand (415-5359 Ωm) were delineated from the resistivity sections with two thin layers of silty lateritic clay and clayey sand defined in the texturally filtered resistivity sections. This study concluded that the presence of incompetent thick clayey materials (18 m) beneath the study area makes it unsuitable for shallow foundation. Deep foundation involving piling through the clayey layers to the competent sand at 20 m depth was recommended.

Keywords: cone penetrometer, foundation, lithologic texture, resistivity section, standard penetration test

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4762 Reconciling Religion and Feminism: A Case Study of Muslim Women's Rights Activism in India

Authors: Qazi Sarah Rasheed

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Feminism and religion have been regarded as opposing binaries. The reason being that religion is regarded as a tool to legitimize the patriarchal control over women, and therefore, it stands in contrast with the basic feminist principle of gender equity. Hence, the issue of incompatibility between religion and gender parity is often discussed by the feminist as well as secular/liberal discourses, but the feminist discourse has suffered a serious backlash in the recent times for it alienates those women who want to liberate but not at the expense of their religious identity. Though in the Western feminist thought, religion is regarded as a tool of patriarchy that promotes women’s suppression, but for many women, religion can be a source of liberation that advances their rights. The feminists in general, fail to realize that religion, as a social phenomenon may not necessarily promote a series of dogmatic doctrines which are inevitably retrogressive or instinctively status-quoist especially when it comes to the social reforms affecting gender orders. The traditional institution of religion could be instrumental to provide what the women in contemporary situation demand. This paper highlights how the Muslim women in India negotiate and mediate this opposition in an Islamic context. To advance the socio-legal recognition of women’s rights, they question the male privilege and patriarchy in a meaningful way without challenging their Islamic doctrines and try to build a feminist consciousness from within religion.

Keywords: feminism, Islam, Muslim women's rights, religious identity

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4761 A Comprehensive Study on Freshwater Aquatic Life Health Quality Assessment Using Physicochemical Parameters and Planktons as Bio Indicator in a Selected Region of Mahaweli River in Kandy District, Sri Lanka

Authors: S. M. D. Y. S. A. Wijayarathna, A. C. A. Jayasundera

Abstract:

Mahaweli River is the longest and largest river in Sri Lanka and it is the major drinking water source for a large portion of 2.5 million inhabitants in the Central Province. The aim of this study was to the determination of water quality and aquatic life health quality in a selected region of Mahaweli River. Six sampling locations (Site 1: 7° 16' 50" N, 80° 40' 00" E; Site 2: 7° 16' 34" N, 80° 40' 27" E; Site 3: 7° 16' 15" N, 80° 41' 28" E; Site 4: 7° 14' 06" N, 80° 44' 36" E; Site 5: 7° 14' 18" N, 80° 44' 39" E; Site 6: 7° 13' 32" N, 80° 46' 11" E) with various anthropogenic activities at bank of the river were selected for a period of three months from Tennekumbura Bridge to Victoria Reservoir. Temperature, pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Dissolved Oxygen (DO), 5-day Biological Oxygen Demand (BOD5), Total Suspended Solids (TSS), hardness, the concentration of anions, and metal concentration were measured according to the standard methods, as physicochemical parameters. Planktons were considered as biological parameters. Using a plankton net (20 µm mesh size), surface water samples were collected into acid washed dried vials and were stored in an ice box during transportation. Diversity and abundance of planktons were identified within 4 days of sample collection using standard manuals of plankton identification under the light microscope. Almost all the measured physicochemical parameters were within the CEA standards limits for aquatic life, Sri Lanka Standards (SLS) or World Health Organization’s Guideline for drinking water. Concentration of orthophosphate ranged between 0.232 to 0.708 mg L-1, and it has exceeded the standard limit of aquatic life according to CEA guidelines (0.400 mg L-1) at Site 1 and Site 2, where there is high disturbance by cultivations and close households. According to the Pearson correlation (significant correlation at p < 0.05), it is obvious that some physicochemical parameters (temperature, DO, TDS, TSS, phosphate, sulphate, chloride fluoride, and sodium) were significantly correlated to the distribution of some plankton species such as Aulocoseira, Navicula, Synedra, Pediastrum, Fragilaria, Selenastrum, Oscillataria, Tribonema and Microcystis. Furthermore, species that appear in blooms (Aulocoseira), organic pollutants (Navicula), and phosphate high eutrophic water (Microcystis) were found, indicating deteriorated water quality in Mahaweli River due to agricultural activities, solid waste disposal, and release of domestic effluents. Therefore, it is necessary to improve environmental monitoring and management to control the further deterioration of water quality of the river.

Keywords: bio indicator, environmental variables, planktons, physicochemical parameters, water quality

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4760 A Dynamic Cardiac Single Photon Emission Computer Tomography Using Conventional Gamma Camera to Estimate Coronary Flow Reserve

Authors: Maria Sciammarella, Uttam M. Shrestha, Youngho Seo, Grant T. Gullberg, Elias H. Botvinick

Abstract:

Background: Myocardial perfusion imaging (MPI) is typically performed with static imaging protocols and visually assessed for perfusion defects based on the relative intensity distribution. Dynamic cardiac SPECT, on the other hand, is a new imaging technique that is based on time varying information of radiotracer distribution, which permits quantification of myocardial blood flow (MBF). In this abstract, we report a progress and current status of dynamic cardiac SPECT using conventional gamma camera (Infinia Hawkeye 4, GE Healthcare) for estimation of myocardial blood flow and coronary flow reserve. Methods: A group of patients who had high risk of coronary artery disease was enrolled to evaluate our methodology. A low-dose/high-dose rest/pharmacologic-induced-stress protocol was implemented. A standard rest and a standard stress radionuclide dose of ⁹⁹ᵐTc-tetrofosmin (140 keV) was administered. The dynamic SPECT data for each patient were reconstructed using the standard 4-dimensional maximum likelihood expectation maximization (ML-EM) algorithm. Acquired data were used to estimate the myocardial blood flow (MBF). The correspondence between flow values in the main coronary vasculature with myocardial segments defined by the standardized myocardial segmentation and nomenclature were derived. The coronary flow reserve, CFR, was defined as the ratio of stress to rest MBF values. CFR values estimated with SPECT were also validated with dynamic PET. Results: The range of territorial MBF in LAD, RCA, and LCX was 0.44 ml/min/g to 3.81 ml/min/g. The MBF between estimated with PET and SPECT in the group of independent cohort of 7 patients showed statistically significant correlation, r = 0.71 (p < 0.001). But the corresponding CFR correlation was moderate r = 0.39 yet statistically significant (p = 0.037). The mean stress MBF value was significantly lower for angiographically abnormal than that for the normal (Normal Mean MBF = 2.49 ± 0.61, Abnormal Mean MBF = 1.43 ± 0. 0.62, P < .001). Conclusions: The visually assessed image findings in clinical SPECT are subjective, and may not reflect direct physiologic measures of coronary lesion. The MBF and CFR measured with dynamic SPECT are fully objective and available only with the data generated from the dynamic SPECT method. A quantitative approach such as measuring CFR using dynamic SPECT imaging is a better mode of diagnosing CAD than visual assessment of stress and rest images from static SPECT images Coronary Flow Reserve.

Keywords: dynamic SPECT, clinical SPECT/CT, selective coronary angiograph, ⁹⁹ᵐTc-Tetrofosmin

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4759 Survey of Related Field for Artificial Intelligence Window Development

Authors: Young Kwon Yang, Bo Rang Park, Hyo Eun Lee, Tea Won Kim, Eun Ji Choi, Jin Chul Park

Abstract:

To develop an artificial intelligence based automatic ventilation system, recent research trends were analyzed and analyzed. This research method is as follows. In the field of architecture and window technology, the use of artificial intelligence, the existing study of machine learning model and the theoretical review of the literature were carried out. This paper collected journals such as Journal of Energy and Buildings, Journal of Renewable and Sustainable Energy Reviews, and articles published on Web-sites. The following keywords were searched for articles from 2000 to 2016. We searched for the above keywords mainly in the title, keyword, and abstract. As a result, the global artificial intelligence market is expected to grow at a CAGR of 14.0% from USD127bn in 2015 to USD165bn in 2017. Start-up investments in artificial intelligence increased from the US $ 45 million in 2010 to the US $ 310 million in 2015, and the number of investments increased from 6 to 54. Although AI is making efforts to advance to advanced countries, the level of technology is still in its infant stage. Especially in the field of architecture, artificial intelligence (AI) is very rare. Based on the data of this study, it is expected that the application of artificial intelligence and the application of architectural field will be revitalized through the activation of artificial intelligence in the field of architecture and window.

Keywords: artificial intelligence, window, fine dust, thermal comfort, ventilation system

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4758 Cross Professional Team-Assisted Teaching Effectiveness

Authors: Shan-Yu Hsu, Hsin-Shu Huang

Abstract:

The main purpose of this teaching research is to design an interdisciplinary team-assisted teaching method for trainees and interns and review the effectiveness of this teaching method on trainees' understanding of peritoneal dialysis. The teaching research object is the fifth and sixth-grade trainees in a medical center's medical school. The teaching methods include media teaching, demonstration of technical operation, face-to-face communication with patients, special case discussions, and field visits to the peritoneal dialysis room. Evaluate learning effectiveness before, after, and verbally. Statistical analysis was performed using the SPSS paired-sample t-test to analyze whether there is a difference in peritoneal dialysis professional cognition before and after teaching intervention. Descriptive statistics show that the average score of the previous test is 74.44, the standard deviation is 9.34, the average score of the post-test is 95.56, and the standard deviation is 5.06. The results of the t-test of the paired samples are shown as p-value = 0.006, showing the peritoneal dialysis professional cognitive test. Significant differences were observed before and after. The interdisciplinary team-assisted teaching method helps trainees and interns to improve their professional awareness of peritoneal dialysis. At the same time, trainee physicians have positive feedback on the inter-professional team-assisted teaching method. This teaching research finds that the clinical ability development education of trainees and interns can provide cross-professional team-assisted teaching methods to assist clinical teaching guidance.

Keywords: monitor quality, patient safety, health promotion objective, cross-professional team-assisted teaching methods

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4757 Interoperability Standard for Data Exchange in Educational Documents in Professional and Technological Education: A Comparative Study and Feasibility Analysis for the Brazilian Context

Authors: Giovana Nunes Inocêncio

Abstract:

The professional and technological education (EPT) plays a pivotal role in equipping students for specialized careers, and it is imperative to establish a framework for efficient data exchange among educational institutions. The primary focus of this article is to address the pressing need for document interoperability within the context of EPT. The challenges, motivations, and benefits of implementing interoperability standards for digital educational documents are thoroughly explored. These documents include EPT completion certificates, academic records, and curricula. In conjunction with the prior abstract, it is evident that the intersection of IT governance and interoperability standards holds the key to transforming the landscape of technical education in Brazil. IT governance provides the strategic framework for effective data management, aligning with educational objectives, ensuring compliance, and managing risks. By adopting interoperability standards, the technical education sector in Brazil can facilitate data exchange, enhance data security, and promote international recognition of qualifications. The utilization of the XML (Extensible Markup Language) standard further strengthens the foundation for structured data exchange, fostering efficient communication, standardization of curricula, and enhancing educational materials. The IT governance, interoperability standards, and data management critical role in driving the quality, efficiency, and security of technical education. The adoption of these standards fosters transparency, stakeholder coordination, and regulatory compliance, ultimately empowering the technical education sector to meet the dynamic demands of the 21st century.

Keywords: interoperability, education, standards, governance

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4756 Recycling in Bogotá: A SWOT Analysis of Three Associations to Evaluate the Integrating the Informal Sector into Solid Waste Management

Authors: Clara Inés Pardo Martínez

Abstract:

In emerging economies, recycling is an opportunity for the cities to increase the lifespan of sanitary landfills, reduce the costs of the solid waste management, decrease the environmental problems of the waste treatment through reincorporate waste in the productive cycle and protect and develop people’s livelihoods of informal waste pickers. However, few studies have analysed the possibilities and strategies to integrate formal and informal sectors in the solid waste management for the benefit of both. This study seek to make a strength, weakness, opportunity, and threat (SWOT) analysis in three recycling associations of Bogotá with the aim to understand and determine the situation of recycling from perspective of informal sector in its transition to enter as authorized waste providers. Data used in the analysis are derived from multiple strategies such as literature review, the Bogota’s recycling database, focus group meetings, governmental reports, national laws and regulations and specific interviews with key stakeholders. Results of this study show as the main stakeholders of formal and informal sector of waste management can identify the internal and internal conditions of recycling in Bogotá. Several strategies were designed based on the SWOTs determined, could be useful for Bogotá to advance and promote recycling as a key strategy for integrated sustainable waste management in the city.

Keywords: Bogotá, recycling, solid waste management, SWOT analysis

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4755 Development of Structural Deterioration Models for Flexible Pavement Using Traffic Speed Deflectometer Data

Authors: Sittampalam Manoharan, Gary Chai, Sanaul Chowdhury, Andrew Golding

Abstract:

The primary objective of this paper is to present a simplified approach to develop the structural deterioration model using traffic speed deflectometer data for flexible pavements. Maintaining assets to meet functional performance is not economical or sustainable in the long terms, and it would end up needing much more investments for road agencies and extra costs for road users. Performance models have to be included for structural and functional predicting capabilities, in order to assess the needs, and the time frame of those needs. As such structural modelling plays a vital role in the prediction of pavement performance. A structural condition is important for the prediction of remaining life and overall health of a road network and also major influence on the valuation of road pavement. Therefore, the structural deterioration model is a critical input into pavement management system for predicting pavement rehabilitation needs accurately. The Traffic Speed Deflectometer (TSD) is a vehicle-mounted Doppler laser system that is capable of continuously measuring the structural bearing capacity of a pavement whilst moving at traffic speeds. The device’s high accuracy, high speed, and continuous deflection profiles are useful for network-level applications such as predicting road rehabilitations needs and remaining structural service life. The methodology adopted in this model by utilizing time series TSD maximum deflection (D0) data in conjunction with rutting, rutting progression, pavement age, subgrade strength and equivalent standard axle (ESA) data. Then, regression analyses were undertaken to establish a correlation equation of structural deterioration as a function of rutting, pavement age, seal age and equivalent standard axle (ESA). This study developed a simple structural deterioration model which will enable to incorporate available TSD structural data in pavement management system for developing network-level pavement investment strategies. Therefore, the available funding can be used effectively to minimize the whole –of- life cost of the road asset and also improve pavement performance. This study will contribute to narrowing the knowledge gap in structural data usage in network level investment analysis and provide a simple methodology to use structural data effectively in investment decision-making process for road agencies to manage aging road assets.

Keywords: adjusted structural number (SNP), maximum deflection (D0), equant standard axle (ESA), traffic speed deflectometer (TSD)

Procedia PDF Downloads 147
4754 Evaluation of 3D Templated Synthetic Vascular Graft Compared with Standard Graft in a Rat Model

Authors: Won-Min Jo, Suk-Hee Park, Tae-Hee Kim

Abstract:

Although the number of vascular surgeries using vascular grafts is increasing, they are limited by vascular graft-related complications and size discrepancy. Current efforts to develop the ideal synthetic vascular graft for clinical application using tissue engineering or 3D printing are far from satisfactory. Therefore, we aimed to re-design the vascular graft with modified materials and 3D printing techniques and also demonstrated the improved applications of our vascular graft clinically. We designed the 3D printed polyvinyl alcohol (PVA) templates according to the vessel size and shape, and these were dip-coated with salt-suspended thermoplastic polyurethane (TPU). Next, the core template was removed to obtain a customized porous TPU graft. The mechanical testing and cytotoxicity studies of the synthetic 3D templated vascular grafts (3DT) were more appropriate compared with commercially available polytetrafluoroethylene (PTFE) grafts (ePTFE; standard graft, SG) for clinical use. Finally, we performed implantation of the 3DTs and SGs into the rat abdominal aorta as a patch technique. Four groups of the animal model (SG_7 days, SG_30 days, 3DT_7 days, and 3DT_30 days) were enrolled in this study. The abdominal aorta was surgically opened and sutured with SG or 3DT with 8/0 Prolene. The degree of endothelial cell activation, neovascularization, thrombus formation, calcification, inflammatory infiltrates, and fibrosis were analyzed histopathologically. There was significantly decreased thrombogenesis in the group treated with the 3DT for 30 days compared with the group treated with the SG for 7 and 30 days, and the 3DT for 7 days. In addition, the group treated with the 3DT for 30 days may also have shown increased postoperative endothelialization in the early stages. In conclusion, this study suggests the possibility of using the 3DT as an SG substitute in vascular surgery.

Keywords: 3D templated graft, hrombogenesis, calcification, inflammation

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4753 Comparative Studies and Optimization of Biodiesel Production from Oils of Selected Seeds of Nigerian Origin

Authors: Ndana Mohammed, Abdullahi Musa Sabo

Abstract:

The oils used in this work were extracted from seeds of Ricinuscommunis, Heaveabrasiliensis, Gossypiumhirsutum, Azadirachtaindica, Glycin max and Jatrophacurcasby solvent extraction method using n-hexane, and gave the yield of 48.00±0.00%, 44.30±0.52%, 45.50±0.64%, 47.60±0.51%, 41.50±0.32% and 46.50±0.71% respectively. However these feed stocks are highly challenging to trans-esterification reaction because they were found to contain high amount of free fatty acids (FFA) (6.37±0.18, 17.20±0.00, 6.14±0.05, 8.60±0.14, 5.35±0.07, 4.24±0.02mgKOH/g) in order of the above. As a result, two-stage trans-esterification reactions process was used to produce biodiesel; Acid esterification was used to reduce high FFA to 1% or less, and the second stage involve the alkaline trans-esterification/optimization of process condition to obtain high yield quality biodiesel. The salient features of this study include; characterization of oils using AOAC, AOCS standard methods to reveal some properties that may determine the viability of sample seeds as potential feed stocks for biodiesel production, such as acid value, saponification value, Peroxide value, Iodine value, Specific gravity, Kinematic viscosity, and free fatty acid profile. The optimization of process parameters in biodiesel production was investigated. Different concentrations of alkaline catalyst (KOH) (0.25, 0.5, 0.75, 1.0 and 1.50w/v, methanol/oil molar ratio (3:1, 6:1, 9:1, 12:1, and 15:1), reaction temperature (500 C, 550 C, 600 C, 650 C, 700 C), and the rate of stirring (150 rpm,225 rpm,300 rpm and 375 rpm) were used for the determination of optimal condition at which maximum yield of biodiesel would be obtained. However, while optimizing one parameter other parameters were kept fixed. The result shows the optimal biodiesel yield at a catalyst concentration of 1%, methanol/oil molar ratio of 6:1, except oil from ricinuscommunis which was obtained at 9:1, the reaction temperature of 650 C was observed for all samples, similarly the stirring rate of 300 rpm was also observed for all samples except oil from ricinuscommunis which was observed at 375 rpm. The properties of biodiesel fuel were evaluated and the result obtained conformed favorably to ASTM and EN standard specifications for fossil diesel and biodiesel. Therefore biodiesel fuel produced can be used as substitute for fossil diesel. The work also reports the result of the study on the evaluation of the effect of the biodiesel storage on its physicochemical properties to ascertain the level of deterioration with time. The values obtained for the entire samples are completely out of standard specification for biodiesel before the end of the twelve months test period, and are clearly degraded. This suggests the biodiesels from oils of Ricinuscommunis, Heaveabrasiliensis, Gossypiumhirsutum, Azadirachtaindica, Glycin max and Jatrophacurcascannot be stored beyond twelve months.

Keywords: biodiesel, characterization, esterification, optimization, transesterification

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4752 Social Change and Cultural Sustainability in the Wake of Digital Media Revolution in South Asia

Authors: Binod C. Agrawal

Abstract:

In modern history, industrial and media merchandising in South Asia from East Asia, Europe, United States and other countries of the West is over 200 years old. Hence, continued external technology and media exposure is not a new experience in multi-lingual and multi religious South Asia which evolved cultural means to withstand structural change. In the post-World War II phase, media exposure especially of telecommunication, film, Internet, radio, print media and television have increased manifold. South Asia did not lose any time in acquiring and adopting digital media accelerated by chip revolution, computer and satellite communication. The penetration of digital media and utilization are exceptionally high though the spread has an unequal intensity, use and effects. The author argues that industrial and media products are “cultural products” apart from being “technological products”; hence their influences are most felt in the cultural domain which may lead to blunting of unique cultural specifics in the multi-cultural, multi-lingual and multi religious South Asia. Social scientists, political leaders and parents have voiced concern of “Cultural domination”, “Digital media colonization” and “Westernization”. Increased digital media access has also opened up doors of pornography and other harmful information that have sparked fresh debates and discussions about serious negative, harmful, and undesirable social effects especially among youth. Within ‘techno-social’ perspective, based on recent research studies, the paper aims to describe and analyse possible socio-economic change due to digital media penetration. Further, analysis supports the view that the ancient multi-lingual and multi-religious cultures of South Asia due to inner cultural strength may sustain without setting in a process of irreversible structural changes in South Asia.

Keywords: cultural sustainability, digital media effects, digital media impact in South Asia, social change in South Asia

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4751 Accuracy of VCCT for Calculating Stress Intensity Factor in Metal Specimens Subjected to Bending Load

Authors: Sanjin Kršćanski, Josip Brnić

Abstract:

Virtual Crack Closure Technique (VCCT) is a method used for calculating stress intensity factor (SIF) of a cracked body that is easily implemented on top of basic finite element (FE) codes and as such can be applied on the various component geometries. It is a relatively simple method that does not require any special finite elements to be used and is usually used for calculating stress intensity factors at the crack tip for components made of brittle materials. This paper studies applicability and accuracy of VCCT applied on standard metal specimens containing trough thickness crack, subjected to an in-plane bending load. Finite element analyses were performed using regular 4-node, regular 8-node and a modified quarter-point 8-node 2D elements. Stress intensity factor was calculated from the FE model results for a given crack length, using data available from FE analysis and a custom programmed algorithm based on virtual crack closure technique. Influence of the finite element size on the accuracy of calculated SIF was also studied. The final part of this paper includes a comparison of calculated stress intensity factors with results obtained from analytical expressions found in available literature and in ASTM standard. Results calculated by this algorithm based on VCCT were found to be in good correlation with results obtained with mentioned analytical expressions.

Keywords: VCCT, stress intensity factor, finite element analysis, 2D finite elements, bending

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4750 The Contribution of Community Involvement in Heritage Management

Authors: Esraa Alhadad

Abstract:

Recently, there has been considerable debate surrounding the definition, conservation, and management of heritage. Over the past few years, there has been a growing call for the inclusion of local communities in heritage management. However, the perspectives on involvement, especially concerning key stakeholders like community members, often diverge significantly. While the theoretical foundation for community involvement is reasonably established, the application of this approach in heritage management has been sluggish. Achieving a balance to fulfill the diverse goals of stakeholders in any involvement project proves challenging in practice. Consequently, there is a dearth of empirical studies exploring the practical implications of effective tools in heritage management, and limited indication exists to persuade current authorities, such as governmental organizations, to share their influence with local community members. This research project delves into community involvement within heritage management as a potent means of constructing a robust management framework. Its objective is to assess both the extent and caliber of involvement within the management of heritage sites overall, utilizing a cultural mapping-centered methodology. The findings of this study underscore the significance of engaging the local community in both heritage management and planning endeavors. Ultimately, this investigation furnishes crucial empirical evidence and extrapolates valuable theoretical and practical insights that advance understanding of cultural mapping in pivotal areas, including the catalysts for involvement and collaborative decision-making processes.

Keywords: community involvement, heritage management, cultural mapping, stakeholder mangement

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4749 Improvement of Visual Acuity in Patient Undergoing Occlusion Therapy

Authors: Rajib Husain, Mezbah Uddin, Mohammad Shamsal Islam, Rabeya Siddiquee

Abstract:

Purpose: To determine the improvement of visual acuity in patients undergoing occlusion therapy. Methods: This was a prospective hospital-based study of newly diagnosed of amblyopia seen at the pediatric clinic of Chittagong Eye Infirmary & Training Complex. There were 32 refractive amblyopia subjects were examined & questionnaire was piloted. Included were all patients diagnosed with refractive amblyopia between 5 to 8 years, without previous amblyopia treatment, and whose parents were interested to participate in the study. Patients diagnosed with strabismic amblyopia were excluded. Patients were first corrected with the best correction for a month. When the VA in the amblyopic eye did not improve over a month, then occlusion treatment was started. Occlusion was done daily for 6-8 h together with vision therapy. The occlusion was carried out for three months. Results: Out of study 32 children, 31 of them have a good compliance of amblyopic treatment whereas one child has poor compliance. About 6% Children have amblyopia from Myopia, 7% Hyperopia, 32% from myopic astigmatism, 42% from hyperopic astigmatism and 13% have mixed astigmatism. The mean and Standard deviation of present average VA was 0.452±0.275 Log MAR and after an intervention of amblyopia therapy with vision therapy mean and Standard deviation VA was 0.155±0.157 Log MAR. Out of total respondent 21.85% have BCVA in range from (0-.2) log MAR, 37.5% have BCVA in range from (0.22-0.5) log MAR, 35.95% have in range from (0.52-0.8) log MAR, 4.7% have in range from (0.82-1) log MAR and after intervention of occlusion therapy with vision therapy 76.6% have VA in range from (0-.2) log MAR, 21.85% have VA in range from (0.22-0.5) log MAR, 1.5% have in range from (0.52-0.8) log MAR. Conclusion: Amblyopia is a most important factor in pediatric age group because it can lead to visual impairment. Thus, this study concludes that occlusion therapy with vision therapy is probably one of the best treatment methods for amblyopic patients (age 5-8 years), and compliance and age were the most critical factor predicting a successful outcome.

Keywords: amblyopia, occlusion therapy, vision therapy, eccentric fixation, visuoscopy

Procedia PDF Downloads 501
4748 The Reproducibility and Repeatability of Modified Likelihood Ratio for Forensics Handwriting Examination

Authors: O. Abiodun Adeyinka, B. Adeyemo Adesesan

Abstract:

The forensic use of handwriting depends on the analysis, comparison, and evaluation decisions made by forensic document examiners. When using biometric technology in forensic applications, it is necessary to compute Likelihood Ratio (LR) for quantifying strength of evidence under two competing hypotheses, namely the prosecution and the defense hypotheses wherein a set of assumptions and methods for a given data set will be made. It is therefore important to know how repeatable and reproducible our estimated LR is. This paper evaluated the accuracy and reproducibility of examiners' decisions. Confidence interval for the estimated LR were presented so as not get an incorrect estimate that will be used to deliver wrong judgment in the court of Law. The estimate of LR is fundamentally a Bayesian concept and we used two LR estimators, namely Logistic Regression (LoR) and Kernel Density Estimator (KDE) for this paper. The repeatability evaluation was carried out by retesting the initial experiment after an interval of six months to observe whether examiners would repeat their decisions for the estimated LR. The experimental results, which are based on handwriting dataset, show that LR has different confidence intervals which therefore implies that LR cannot be estimated with the same certainty everywhere. Though the LoR performed better than the KDE when tested using the same dataset, the two LR estimators investigated showed a consistent region in which LR value can be estimated confidently. These two findings advance our understanding of LR when used in computing the strength of evidence in handwriting using forensics.

Keywords: confidence interval, handwriting, kernel density estimator, KDE, logistic regression LoR, repeatability, reproducibility

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4747 Studies of Rule Induction by STRIM from the Decision Table with Contaminated Attribute Values from Missing Data and Noise — in the Case of Critical Dataset Size —

Authors: Tetsuro Saeki, Yuichi Kato, Shoutarou Mizuno

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STRIM (Statistical Test Rule Induction Method) has been proposed as a method to effectively induct if-then rules from the decision table which is considered as a sample set obtained from the population of interest. Its usefulness has been confirmed by simulation experiments specifying rules in advance, and by comparison with conventional methods. However, scope for future development remains before STRIM can be applied to the analysis of real-world data sets. The first requirement is to determine the size of the dataset needed for inducting true rules, since finding statistically significant rules is the core of the method. The second is to examine the capacity of rule induction from datasets with contaminated attribute values created by missing data and noise, since real-world datasets usually contain such contaminated data. This paper examines the first problem theoretically, in connection with the rule length. The second problem is then examined in a simulation experiment, utilizing the critical size of dataset derived from the first step. The experimental results show that STRIM is highly robust in the analysis of datasets with contaminated attribute values, and hence is applicable to realworld data.

Keywords: rule induction, decision table, missing data, noise

Procedia PDF Downloads 392
4746 CD133 and CD44 - Stem Cell Markers for Prediction of Clinically Aggressive Form of Colorectal Cancer

Authors: Ognen Kostovski, Svetozar Antovic, Rubens Jovanovic, Irena Kostovska, Nikola Jankulovski

Abstract:

Introduction:Colorectal carcinoma (CRC) is one of the most common malignancies in the world. The cancer stem cell (CSC) markers are associated with aggressive cancer types and poor prognosis. The aim of study was to determine whether the expression of colorectal cancer stem cell markers CD133 and CD44 could be significant in prediction of clinically aggressive form of CRC. Materials and methods: Our study included ninety patients (n=90) with CRC. Patients were divided into two subgroups: with metatstatic CRC and non-metastatic CRC. Tumor samples were analyzed with standard histopathological methods, than was performed immunohistochemical analysis with monoclonal antibodies against CD133 and CD44 stem cell markers. Results: High coexpression of CD133 and CD44 was observed in 71.4% of patients with metastatic disease, compared to 37.9% in patients without metastases. Discordant expression of both markers was found in 8% of the subgroup with metastatic CRC, and in 13.4% of the subgroup without metastatic CRC. Statistical analyses showed a significant association of increased expression of CD133 and CD44 with the disease stage, T - category and N - nodal status. With multiple regression analysis the stage of disease was designate as a factor with the greatest statistically significant influence on expression of CD133 (p <0.0001) and CD44 (p <0.0001). Conclusion: Our results suggest that the coexpression of CD133 and CD44 have an important role in prediction of clinically aggressive form of CRC. Both stem cell markers can be routinely implemented in standard pathohistological diagnostics and can be useful markers for pre-therapeutic oncology screening.

Keywords: colorectal carcinoma, stem cells, CD133+, CD44+

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4745 Direct CP Violation in Baryonic B-Hadron Decays

Authors: C. Q. Geng, Y. K. Hsiao

Abstract:

We study direct CP-violating asymmetries (CPAs) in the baryonic B decays of B- -> p\bar{p}M and Λb decays of Λb ®pM andΛb -> J/ΨpM with M=π-, K-,ρ-,K*- based on the generalized factorization method in the standard model (SM). In particular, we show that the CPAs in the vector modes of B-®p\bar{p}K* and Λb -> p K*- can be as large as 20%. We also discuss the simplest purely baryonic decays of Λb-> p\bar{p}n, p\bar{p}Λ, Λ\bar{p}Λ, and Λ\bar{Λ}Λ. We point out that some of CPAs are promising to be measured by the current as well as future B facilities.

Keywords: CP violation, B decays, baryonic decays, Λb decays

Procedia PDF Downloads 254