Search results for: numerous stenosis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1804

Search results for: numerous stenosis

1234 Investigation of Dry Ice Mixed Novel Hybrid Lubri-Coolant in Sustainable Machining of Ti-6AL-4V Alloy: A Comparison of Experimental and Modelling

Authors: Muhammad Jamil, Ning He, Aqib Mashood Khan, Munish Kumar Gupta

Abstract:

Ti-6Al-4V has numerous applications in the medical, automobile, and aerospace industries due to corrosion resistivity, structural stability, and chemical inertness to most fluids at room temperature. These peculiar characteristics are beneficial for their application and present formidable challenges during machining. Machining of Ti-6Al-4V produces an elevated cutting temperature above 1000oC at dry conditions. This accelerates tool wear and reduces product quality. Therefore, there is always a need to employ sustainable/effective coolant/lubricant when machining such alloy. In this study, Finite Element Modeling (FEM) and experimental analysis when cutting Ti-6Al-4V under a distinctly developed dry ice mixed hybrid lubri-coolant are presented. This study aims to model the milling process of Ti-6Al-4V under a proposed novel hybrid lubri-coolant using different cutting speeds and feed per tooth DEFORM® software package was used to conduct the FEM and the numerical model was experimentally validated. A comparison of experimental and simulation results showed a maximum error of no more than 6% for all experimental conditions. In a nutshell, it can be said that the proposed model is effective in predicting the machining temperature precisely.

Keywords: friction coefficient, heat transfer, finite element modeling (FEM), milling Ti-6Al-4V

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1233 Efficiency of Google Translate and Bing Translator in Translating Persian-to-English Texts

Authors: Samad Sajjadi

Abstract:

Machine translation is a new subject increasingly being used by academic writers, especially students and researchers whose native language is not English. There are numerous studies conducted on machine translation, but few investigations have assessed the accuracy of machine translation from Persian to English at lexical, semantic, and syntactic levels. Using Groves and Mundt’s (2015) Model of error taxonomy, the current study evaluated Persian-to-English translations produced by two famous online translators, Google Translate and Bing Translator. A total of 240 texts were randomly selected from different academic fields (law, literature, medicine, and mass media), and 60 texts were considered for each domain. All texts were rendered by the two translation systems and then by four human translators. All statistical analyses were applied using SPSS. The results indicated that Google translations were more accurate than the translations produced by the Bing Translator, especially in the domains of medicine (lexis: 186 vs. 225; semantic: 44 vs. 48; syntactic: 148 vs. 264 errors) and mass media (lexis: 118 vs. 149; semantic: 25 vs. 32; syntactic: 110 vs. 220 errors), respectively. Nonetheless, both machines are reasonably accurate in Persian-to-English translation of lexicons and syntactic structures, particularly from mass media and medical texts.

Keywords: machine translations, accuracy, human translation, efficiency

Procedia PDF Downloads 71
1232 A Methodology for Investigating Public Opinion Using Multilevel Text Analysis

Authors: William Xiu Shun Wong, Myungsu Lim, Yoonjin Hyun, Chen Liu, Seongi Choi, Dasom Kim, Kee-Young Kwahk, Namgyu Kim

Abstract:

Recently, many users have begun to frequently share their opinions on diverse issues using various social media. Therefore, numerous governments have attempted to establish or improve national policies according to the public opinions captured from various social media. In this paper, we indicate several limitations of the traditional approaches to analyze public opinion on science and technology and provide an alternative methodology to overcome these limitations. First, we distinguish between the science and technology analysis phase and the social issue analysis phase to reflect the fact that public opinion can be formed only when a certain science and technology is applied to a specific social issue. Next, we successively apply a start list and a stop list to acquire clarified and interesting results. Finally, to identify the most appropriate documents that fit with a given subject, we develop a new logical filter concept that consists of not only mere keywords but also a logical relationship among the keywords. This study then analyzes the possibilities for the practical use of the proposed methodology thorough its application to discover core issues and public opinions from 1,700,886 documents comprising SNS, blogs, news, and discussions.

Keywords: big data, social network analysis, text mining, topic modeling

Procedia PDF Downloads 288
1231 Developing a Modular Architecture of Apparel Product

Authors: Yu Zhao, Mengqin Sun, Yahui Zhang

Abstract:

Apparel products (or apparel) with the sense of aesthetics, usability (ergonomics) and function are fundamental and varied in people’s daily life. The numerous apparel thus produced by apparel industry, have been triggered many issues, such as the waste of sources and the environmental pollutions. In this study, a hybrid architecture called modular architecture of apparel (MAA) has been proposed to deal with the variety of apparel, and thus to overcome the aforementioned issues. Generally, the establishment of MAA takes advantage of the modular design of a general product that a product is assembled with many modules through their modular interface connector. The development of MAA is to first analyze the structure of apparel in terms of the necessity to form an apparel and the aesthetics, ergonomics, and function of apparel; then to divide apparel into many segments (or module in product design) based on the structure of apparel; to develop modular interfaces and modular interface connectors in terms of the features of apparel’s modules. It is noted that in the general product design, modules of a product are only about the function and ergonomics, but in MAA, the module of aesthetics is developed. Further, an apparel design with employing the MAA is carried out to validate its usefulness and efficiency. There are three contributions out of this study, the first is to overcome the aforementioned issues (i.e. waste of source and environmental pollutions); the second is the improvement of the modular design for product by considering aesthetics; the third is to add the value in realizing the personalized mass production of apparel in the near future.

Keywords: apparel, architecture, modular design, segment

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1230 Policies and Politics of Infrastructure Provisioning in Nigeria

Authors: Olufemi Adedamola Oyedele

Abstract:

Infrastructure provision in Nigeria is now at its lowest ebb in spite of its being critical to the socio-economic and political development of any nation. This is partly because the policy that will ensure its adequate provisioning is missing and partly because politics is affecting its provision. Policy is the basic principles by which a government is guided. Infrastructural development is the basis for measuring the performance of governments and it is the foundation of good governance. Demand for infrastructural development is higher and resources used in its provision are limited. Ethnic-interest agitation and lobbying for infrastructure provision are common things in multi-ethnic state like Nigeria. Most infrastructures are now decayed and need repair or replacement. Government is the system that organizes, control and sensitizes the people in a society in other for all to have an acceptable level of living. Governments have the power to put in place all measures that they deem fit will make an environment conducive for living for everybody. Infrastructure development in any environment requires needs assessment, feasibility and viability studies and carrying out physical development of the project. The challenge in Nigeria is largely carrying out development where they are not needed but where the people are loyal. There are numerous abandoned projects because they were started due to politics and not because they are feasible. Policies and politics greatly affect infrastructure provisioning in Nigeria and this is the premise of this paper.

Keywords: infrastructure challenges, infrastructure development, policy making, politics, project finance

Procedia PDF Downloads 268
1229 Diverse Survey Sampling of US Population Reveals Race/Ethnicity Differences in Perceptions of Dog Breed Personalities

Authors: J. A. Villarreal, D. S. Ha., A. Smith, J. C. Ha

Abstract:

Numerous dogs are living in shelters seeking homes. Perceptions of dog personality based on breed type have been shown to influence adoptability. Past research has focused primarily on Caucasian female samples. This study provides a more diverse sample within the US. Of the respondents, 558 identified as White/Caucasian, 395 identified as Black/African American, 123 identified as Hispanic/Latinx, and 46 identified as Asian/Asian American. 29.6% of respondents identified as male and 70.4% identified as female. Initial analyses indicate significant differences in race/ethnicity in the association of the personality terms of “Dangerous”, “Calm”, and “Energetic” with dog breeds. Black/African-American respondents were more likely to associate the term “Dangerous” with almost all breeds assessed in this survey, followed by Hispanic/Latinx, and lastly by White/Caucasian and Asian/Asian American. Higher annual income respondents were less likely to associate the term “Calm” with most breeds and lower-income respondents were less likely to ascribe the term “Dangerous” to Pit Bull Terriers. Further analyses are underway. These findings can help dog adoption programs promote more diversity in potential adopters.

Keywords: breed, diversity, dog, ethnicity, personality

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1228 Employing Innovative Pedagogy: Collaborative (Online) Learning and Teaching In An International Setting

Authors: Sonja Gögele, Petra Kletzenbauer

Abstract:

International strategies are ranked as one of the core activities in the development plans of Austrian universities. This has led to numerous promising activities in terms of internationalization (i.e. development of international degree programmes, increased staff, and student mobility, and blended international projects). The latest innovative approach are so called Blended Intensive Programmes (BIP), which combine jointly delivered teaching and learning elements of at least three participating ERASMUS universities in a virtual and short-term mobility setup. Students who participate in BIP can maintain their study plans at their home institution and include BIP as a parallel activity. This paper presents the experiences of this programme on the topic of sustainable computing hosted by the University of Applied Sciences FH JOANNEUM. By means of an online survey and face-to-face interviews with all stakeholders (20 students, 8 professors), the empirical study addresses the challenges of hosting an international blended learning programme (i.e. virtual phase and on-site intensive phase) and discusses the impact of such activities in terms of innovative pedagogy (i.e. virtual collaboration, research-based learning).

Keywords: internationalization, collaborative learning, blended intensive programme, pedagogy

Procedia PDF Downloads 128
1227 An Evaluation of the Impact of Social Media on Nigerian Youths

Authors: Haruna Shola Adeosun, Lekan M. Togunwa, Ajoke F. Adebiyi

Abstract:

This paper examines the impact of social media on Nigerian Youths particularly in Nigeria. This study reviewed secondary sources data. The research adopted survey method which involves the use of questionnaire that was administered to gather primary data analysis and presentation were done with the use of tables, figures, percentages and chi-square were used to test the hypotheses formulated. The study revealed that social media consumers, especially Facebook are prone to the benefits or risks aspect of its contents. At this expense, what user derived, seeks, sought and gains from such media depend on the motive they are being used for. The study also revealed that users have the tendency to be positively influenced through heavy or over exposure to numerous contents that are damaging and harmful. This means that social media usage may be considered as good or bad. As its contents may or may not subject consumers to vulnerable use depending on what is saved from it. The study recommends that the use of Facebook should be subjected to gate keeping and monitoring in order to control the activities of users that embrace depression, bullying, sexing and sexual harassment as a way of life. Parents should close watch on their children and caution them towards cultivating the habit of over exposure to social sites so at to protect them form risks social media poses.

Keywords: evaluation, impact, soocial media, nigerian youths

Procedia PDF Downloads 282
1226 Investigation on the Capacitive Deionization of Functionalized Carbon Nanotubes (F-CNTs) and Silver-Decorated F-CNTs for Water Softening

Authors: Khrizelle Angelique Sablan, Rizalinda De Leon, Jaeyoung Lee, Joey Ocon

Abstract:

The impending water shortage drives us to find alternative sources of water. One of the possible solutions is desalination of seawater. There are numerous processes by which it can be done and one if which is capacitive deionization. Capacitive deionization is a relatively new technique for water desalination. It utilizes the electric double layer for ion adsorption. Carbon-based materials are commonly used as electrodes for capacitive deionization. In this study, carbon nanotubes (CNTs) were treated in a mixture of nitric and sulfuric acid. The silver addition was also facilitated to incorporate antimicrobial action. The acid-treated carbon nanotubes (f-CNTs) and silver-decorated f-CNTs (Ag@f-CNTs) were used as electrode materials for seawater deionization and compared with CNT and acid-treated CNT. The synthesized materials were characterized using TEM, EDS, XRD, XPS and BET. The electrochemical performance was evaluated using cyclic voltammetry, and the deionization performance was tested on a single cell with water containing 64mg/L NaCl. The results showed that the synthesized Ag@f-CNT-10 H could have better performance than CNT and a-CNT with a maximum ion removal efficiency of 50.22% and a corresponding adsorption capacity of 3.21 mg/g. It also showed antimicrobial activity against E. coli. However, the said material lacks stability as the efficiency decreases with repeated usage of the electrode.

Keywords: capacitive deionization, carbon nanotubes, desalination, acid functionalization, silver

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1225 Design, Optimize the Damping System for Optical Scanning Equipment

Authors: Duy Nhat Tran, Van Tien Pham, Quang Trung Trinh, Tien Hai Tran, Van Cong Bui

Abstract:

In recent years, artificial intelligence and the Internet of Things have experienced significant advancements. Collecting image data and real-time analysis and processing of tasks have become increasingly popular in various aspects of life. Optical scanning devices are widely used to observe and analyze different environments, whether fixed outdoors, mounted on mobile devices, or used in unmanned aerial vehicles. As a result, the interaction between the physical environment and these devices has become more critical in terms of safety. Two commonly used methods for addressing these challenges are active and passive approaches. Each method has its advantages and disadvantages, but combining both methods can lead to higher efficiency. One solution is to utilize direct-drive motors for position control and real-time feedback within the operational range to determine appropriate control parameters with high precision. If the maximum motor torque is smaller than the inertial torque and the rotor reaches the operational limit, the spring system absorbs the impact force. Numerous experiments have been conducted to demonstrate the effectiveness of device protection during operation.

Keywords: optical device, collision safety, collision absorption, precise mechanics

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1224 System for the Detecting of Fake Profiles on Online Social Networks Using Machine Learning and the Bio-Inspired Algorithms

Authors: Sekkal Nawel, Mahammed Nadir

Abstract:

The proliferation of online activities on Online Social Networks (OSNs) has captured significant user attention. However, this growth has been hindered by the emergence of fraudulent accounts that do not represent real individuals and violate privacy regulations within social network communities. Consequently, it is imperative to identify and remove these profiles to enhance the security of OSN users. In recent years, researchers have turned to machine learning (ML) to develop strategies and methods to tackle this issue. Numerous studies have been conducted in this field to compare various ML-based techniques. However, the existing literature still lacks a comprehensive examination, especially considering different OSN platforms. Additionally, the utilization of bio-inspired algorithms has been largely overlooked. Our study conducts an extensive comparison analysis of various fake profile detection techniques in online social networks. The results of our study indicate that supervised models, along with other machine learning techniques, as well as unsupervised models, are effective for detecting false profiles in social media. To achieve optimal results, we have incorporated six bio-inspired algorithms to enhance the performance of fake profile identification results.

Keywords: machine learning, bio-inspired algorithm, detection, fake profile, system, social network

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1223 In vitro Effects of Berberine on the Vitality and Oxidative Profile of Bovine Spermatozoa

Authors: Eva Tvrdá, Hana Greifová, Peter Ivanič, Norbert Lukáč

Abstract:

The aim of this study was to evaluate the dose- and time-dependent in vitro effects of berberine (BER), a natural alkaloid with numerous biological properties on bovine spermatozoa during three time periods (0 h, 2 h, 24 h). Bovine semen samples were diluted and cultivated in physiological saline solution containing 0.5% DMSO together with 200, 100, 50, 10, 5, and 1 μmol/L BER. Spermatozoa motility was assessed using the computer assisted semen analyzer. The viability of spermatozoa was assessed by the metabolic (MTT) assay, production of superoxide radicals was quantified using the nitroblue tetrazolium (NBT) test, and chemiluminescence was used to evaluate the generation of reactive oxygen species (ROS). Cell lysates were prepared and the extent of lipid peroxidation (LPO) was evaluated using the TBARS assay. The results of the movement activity showed a significant increase in the motility during long term cultivation in case of concentrations ranging between 1 and 10 μmol/L BER (P < 0.01; P < 0.001; 24 h). At the same time, supplementation of 1, 5 and 10 μmol/L BER led to a significant preservation of the cell viability (P < 0.001; 24 h). BER addition at a range of 1-50 μmol/L also provided a significantly higher protection against superoxide (P < 0.05) and ROS (P < 0.001; P < 0.01) overgeneration as well as LPO (P < 0.01; P<0.05) after a 24 h cultivation. We may suggest that supplementation of BER to bovine spermatozoa, particularly at concentrations ranging between 1 and 50 μmol/L, may offer protection to the motility, viability and oxidative status of the spermatozoa, particularly notable at 24 h.

Keywords: berberine, bulls, motility, oxidative profile, spermatozoa, viability

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1222 In vitro Investigation of Genotoxic and Antigenotoxic Properties of Gunnera perpensa Roots Extracts

Authors: P. H. Mfengwana, S. S. Mashele, L. Verschaeve, R. Anthonissen, I. T. Manduna

Abstract:

Gunnera perpensa is traditionally used mostly by women for the treatment of different gynaecological related conditions due to its proven uterine contractility effects. The uses of this plant include menstrual pain relief, treatment of infertility and promotion of easy labour. However, even though this plant species has been reported to possess numerous medicinal properties, to author’s best knowledge, its safety has not been investigated. Thus, this study was aimed at investigating the genotoxicity and antigenotoxicity of Gunnera perpensa aqueous, methanol and dichloromethane extracts. The in vitro toxicity of the plant extracts was assessed with the neutral red uptake (NRU) test. Genotoxic and antigenotoxic properties of Gunnera perpensa were investigated using high-throughput assays: bacterial Vitotox test and the alkaline comet assay with and without S9 activation on human C3A cells. Ethyl Methanesulfonate (EMS) and 4-nitroquinoline-oxide (4-NQO) were used as positive controls, respectively. All extracts showed toxicity in a dose-dependent manner; however, that does not mean they were all genotoxic. Methanol extract did show genotoxicity with S9 (metabolism) only at the highest concentration of 500 µg/ml due to increased DNA damage observed, however, no genotoxicity was observed from other concentrations. Therefore, the results show that Gunnera perpensa extracts are genotoxic and not safe for human use.

Keywords: antigenotoxicity, comet test, genotoxicity, Gunnera perpensa, vitotox assay

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1221 Developing House’s Model to Assess the Translation of Key Cultural Texts

Authors: Raja Al-Ghamdi

Abstract:

This paper aims to systematically assess the translation of key cultural texts. The paper, therefore, proposes a modification of the discourse analysis model for translation quality assessment introduced by the linguist Juliane House (1977, 1997, 2015). The data for analysis has been chosen from a religious text that has never been investigated before. It is an overt translation of the biography of Prophet Mohammad. The book is written originally in Arabic and translated into English. A soft copy of the translation, entitled The Sealed Nectar, is posted on numerous websites including the Internet Archive library which offers a free access to everyone. The text abounds with linguistic and cultural phenomena relevant to Islamic and Arab lingua-cultural context which make its translation a challenge, as well as its assessment. Interesting findings show that (1) culturemes are rich points and both the translator’s subjectivity and intervention are apparent in mediating them, (2) given the nature of historical narration, the source text reflects the author’s positive shading, whereas the target text reflects the translator’s axiological orientation as neutrally shaded, and, (3) linguistic gaps, metaphorical expressions and intertextuality are major stimuli to compensation strategies.

Keywords: Arabic-English discourse analysis, key cultural texts, overt translation, quality assessment

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1220 Tool Wear Analysis in 3D Manufactured Ti6AI4V

Authors: David Downey

Abstract:

With the introduction of additive manufacturing (3D printing) to produce titanium (Ti6Al4V) components in the medical/aerospace and automotive industries, intricate geometries can be produced with virtually complete design freedom. However, the consideration of microstructural anisotropy resulting from the additive manufacturing process becomes necessary due to this design flexibility and the need to print a geometric shape that can consist of numerous angles, radii, and swept surfaces. A femoral knee implant serves as an example of a 3D-printed near-net-shaped product. The mechanical properties of the printed components, and consequently, their machinability, are affected by microstructural anisotropy. Currently, finish-machining operations performed on titanium printed parts using selective laser melting (SLM) utilize the same cutting tools employed for processing wrought titanium components. Cutting forces for components manufactured through SLM can be up to 70% higher than those for their wrought counterparts made of Ti6Al4V. Moreover, temperatures at the cutting interface of 3D printed material can surpass those of wrought titanium, leading to significant tool wear. Although the criteria for tool wear may be similar for both 3D printed and wrought materials, the rate of wear during the machining process may differ. The impact of these issues on the choice of cutting tool material and tool lifetimes will be discussed.

Keywords: additive manufacturing, build orientation, microstructural anisotropy, printed titanium Ti6Al4V, tool wear

Procedia PDF Downloads 85
1219 A Study of Industry 4.0 and Digital Transformation

Authors: Ibrahim Bashir, Yahaya Y. Yusuf

Abstract:

The ongoing shift towards Industry 4.0 represents a critical growth factor in the industrial enterprise, where the digital transformation of industries is increasingly seen as a crucial element for competitiveness. This transformation holds substantial potential, yet its full benefits have yet to be realized due to the fragmented approach to introducing Industry 4.0 technologies. Therefore, this pilot study aims to explore the individual and collective impact of Industry 4.0 technologies and digital transformation on organizational performance. Data were collected through a questionnaire-based survey across 51 companies in the manufacturing industry in the United Kingdom. The correlations and multiple linear regression analyses were conducted to assess the relationship and impact between the variables in the study. The results show that Industry 4.0 and digital transformation positively influence organizational performance and that Industry 4.0 technologies positively influence digital transformation. The results of this pilot study indicate that the implementation of Industry 4.0 technology is vital for increasing organizational performance; however, their roles differ largely. The differences are manifest in how the types of Industry 4.0 technologies correlate with how organizations integrate digital technologies into their operations. Hence, there is a clear indication of a strong correlation between Industry 4.0 technology, digital transformation, and organizational performance. Consequently, our study presents numerous pertinent implications that propel the theory of I4.0, digital business transformation (DBT), and organizational performance forward, as well as guide managers in the manufacturing sector.

Keywords: industry 4.0 technologies, digital transformation, digital integration, organizational performance

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1218 Pro-Ecological Antioxidants for Polymeric Composites

Authors: Masek A., Zaborski M.

Abstract:

In our studies, we propose the use of natural, pro-ecological substances such as polyphenols to protect polymers against ageing. In our studies, we plan to focus on the following compounds: polyphenols, gallic acid esters, flavonoides, carotenoids, curcumin and its derivatives, vitamin A, tocochromanoles, betalain. Phyto-compounds will be selected on the basis of available literature and our preliminary studies. So, we will select compounds with various contents of hydroxyl groups and colored substances capable of participating in color oxidation processes. The natural antioxidants which were added to ethylene-octene elastomer (polyolefin elastomer-Engage) and ethylene-nonbornene (TOPAS). Composites were then subjected to numerous ageing: weathering (climat of Floryda), UV (0,7 W/m2), thermo-oxidation ageing (1000C/10days) and thermal-shock (-600C/+1000C) as a function of the aging time. The efficiency of used anti-ageing agents was checked on the base of the changes after the degradation in deformation energy (tensile strength and elongation at the break), cross-link density, color (parameters L,a,b) and values of carbonyl index (based on the spectrum of infra red spectroscopy), OIT (induction oxygen time as performed in using differential scanning calorimeter -DSC) of the vulcanizates. Therefore polyphenols are considered to be the best stabilisers for polymeric composites against to oxidation processes.

Keywords: polymers, flavonoids, stabilization, ageing, oxidation

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1217 Metastatic Ovarian Tumor Discovered Accidentally during Cesarean Section in a 34 Year Old Woman: A Case Report

Authors: Ghada E. Esheba, Ghufran Kheshaifaty, Kholoud Al-Harbi, Wafa'a Al-Harbi, Ala'a Al-Orabi, Moayad Turkistani

Abstract:

Krukenberg tumor is a rare metastatic ovarian carcinoma that usually occurs in female between 30 - 40 year old and rarely seen after menopause. Stomach is the most common primary site. Histopathological features of krukenberg tumors appear as diffuse stromal proliferation, mucus-production, and numerous signet-cells and these tumors spread mostly by lymphatic route. Treatment and prognostic factors are not well established. This study describes a 34 year old female with a unilateral ovarian mass discovered accidentally during cesarean section delivery and it was misdiagnosed as luteoma of pregnancy, but histopathological examination showed a diffuse infiltration of the ovary and omentum by signet ring cells. These findings were not correlated with luteoma of pregnancy or any other types of primary ovarian tumors like surface epithelial tumor, sex cord stromal tumor or germ cell tumor. However, after the analysis of immunohistochemical results (negative CK7, positive CK20 and CDX-2), the finding was the diagnostic of metastatic krukenberg tumor. Two weeks later, the patient was evaluated and a large gastric tumor was found in her stomach and she underwent gastrectomy.

Keywords: CK7, CK20, CDX-2, Krukenburg tumor, metastatic ovarian tumor

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1216 An Optimal Approach for Full-Detailed Friction Model Identification of Reaction Wheel

Authors: Ghasem Sharifi, Hamed Shahmohamadi Ousaloo, Milad Azimi, Mehran Mirshams

Abstract:

The ever-increasing use of satellites demands a search for increasingly accurate and reliable pointing systems. Reaction wheels are rotating devices used commonly for the attitude control of the spacecraft since provide a wide range of torque magnitude and high reliability. The numerical modeling of this device can significantly enhance the accuracy of the satellite control in space. Modeling the wheel rotation in the presence of the various frictions is one of the critical parts of this approach. This paper presents a Dynamic Model Control of a Reaction Wheel (DMCR) in the current control mode. In current-mode, the required current is delivered to the coils in order to achieve the desired torque. During this research, all the friction parameters as viscous and coulomb, motor coefficient, resistance and voltage constant are identified. In order to model identification of a reaction wheel, numerous varying current commands apply on the particular wheel to verify the estimated model. All the parameters of DMCR are identified by classical Levenberg-Marquardt (CLM) optimization method. The experimental results demonstrate that the developed model has an appropriate precise and can be used in the satellite control simulation.

Keywords: experimental modeling, friction parameters, model identification, reaction wheel

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1215 Heterocyclic Ring Extension of Estrone: Synthesis and Cytotoxicity of Fused Pyrin, Pyrimidine and Thiazole Derivatives

Authors: Rafat M. Mohareb

Abstract:

Several D-ring alkylated estrone analogues display exceptionally high affinity for estrogen receptors. In particular, compounds in which an E-ring is formed are known to be involved in the inhibition of steroidogenic enzymes. Such compounds also have an effect on steroid dehydrogenase activity and the ability to inhibit the detrimental action of the steroid sulfatase enzyme. Generally, E-ring extended steroids have been accessed by modification of the C17-ketone in the D-ring by either arylimine or oximino formation, addition of a carbon nucleophile or hydrazone formation. Other approaches have included ketone reduction, silyl enol ether formation or ring-closing metathesis (giving five- or six-membered E-rings). Chemical modification of the steroid D-ring provides a way to alter the functional groups, sizes and stereochemistry of the D-ring, and numerous structure-activity relationships have been established by such synthetic alterations. Steroids bearing heterocycles fused to the D-ring of the steroid nucleus have been of pharmaceutical interest. In the present paper, we report on the efficient synthesis of estrone possessing pyran, pyrimidine and thiazole ring systems. This study focused on the synthesis and biochemical evaluation of newly synthesized heterocyclic compounds which were then subjected through inhibitory evaluations towards human cancer and normal cell lines.

Keywords: estrone, heterocyclization, cytotoxicity, biomedicine

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1214 US-ASEAN Counter Terrorism Cooperation: Maintaining International Security and Avoiding Muslim Stereotypes

Authors: Jordan Daud, Satriya Wibawa, Wahyu Wardhana

Abstract:

The US Global War on Terror has had effect on Southeast Asia as Second Front of Global War on Terror. Since 2001, ASEAN had adopted legal framework to counter the terrorist threat through numerous approach which accommodate various counterterrorism policy of the ten member states. ASEAN have also enhanced multilateral cooperation with US and its allies in Asia Pacific region in addressing terrorist threat, terrorist funding, cyber terrorism and other forms of terrorism. This cooperation is essential to maintain international security and stability and also assure economic development. This work focuses on the US-ASEAN counterterrorism cooperation due to they identified terrorism as a mutual enemy that posed to human security, infrastructure security, and national security. Having in mind that international terrorism usually connected with Muslim community, this paper will also elaborate the concept of Jihad and Islam revivalism in politics to avoid negative image of Islam and Muslim. This paper argues that as region with large Muslim community, Southeast Asia still need to tighten counter terrorism cooperation and also lessening Muslim stereotypes with terrorism through educating public understanding and inter-faith and intra-faith dialogue to create a better world.

Keywords: ASEAN, U.S., counter terrorism, Muslim stereotypes

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1213 Government (Big) Data Ecosystem: Definition, Classification of Actors, and Their Roles

Authors: Syed Iftikhar Hussain Shah, Vasilis Peristeras, Ioannis Magnisalis

Abstract:

Organizations, including governments, generate (big) data that are high in volume, velocity, veracity, and come from a variety of sources. Public Administrations are using (big) data, implementing base registries, and enforcing data sharing within the entire government to deliver (big) data related integrated services, provision of insights to users, and for good governance. Government (Big) data ecosystem actors represent distinct entities that provide data, consume data, manipulate data to offer paid services, and extend data services like data storage, hosting services to other actors. In this research work, we perform a systematic literature review. The key objectives of this paper are to propose a robust definition of government (big) data ecosystem and a classification of government (big) data ecosystem actors and their roles. We showcase a graphical view of actors, roles, and their relationship in the government (big) data ecosystem. We also discuss our research findings. We did not find too much published research articles about the government (big) data ecosystem, including its definition and classification of actors and their roles. Therefore, we lent ideas for the government (big) data ecosystem from numerous areas that include scientific research data, humanitarian data, open government data, industry data, in the literature.

Keywords: big data, big data ecosystem, classification of big data actors, big data actors roles, definition of government (big) data ecosystem, data-driven government, eGovernment, gaps in data ecosystems, government (big) data, public administration, systematic literature review

Procedia PDF Downloads 155
1212 Effective Solvents for Proteins Recovery from Microalgae

Authors: Win Nee Phong, Tau Chuan Ling, Pau Loke Show

Abstract:

From an industrial perspective, the exploitation of microalgae for protein source is of great economical and commercial interest due to numerous attractive characteristics. Nonetheless, the release of protein from microalgae is limited by the multiple layers of the rigid thick cell wall that generally contain a large proportion of cellulose. Thus an efficient cell disruption process is required to rupture the cell wall. The conventional downstream processing methods which typically involve several unit operational steps such as disruption, isolation, extraction, concentration and purification are energy-intensive and costly. To reduce the overall cost and establish a feasible technology for the success of the large-scale production, microalgal industry today demands a more cost-effective and eco-friendly technique in downstream processing. One of the main challenges to extract the proteins from microalgae is the presence of rigid cell wall. This study aims to provide some guidance on the selection of the efficient solvent to facilitate the proteins released during the cell disruption process. The effects of solvent types such as methanol, ethanol, 1-propanol and water in rupturing the microalgae cell wall were studied. It is interesting to know that water is the most effective solvent to recover proteins from microalgae and the cost is cheapest among all other solvents.

Keywords: green, microalgae, protein, solvents

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1211 Preparation of Zno/Ag Nanocomposite and Coating on Polymers for Anti-Infection Biomaterial Application

Authors: Babak Sadeghi, Parisa Ghayomipour

Abstract:

ZnO/Ag nanocomposites coated with polyvinyl chloride (PVC) were prepared by chemical reduction method, for anti-infection biomaterial application. There is a growing interest in attempts in using biomolecular as the templates to grow inorganic nanocomposites in controlled morphology and structure. By optimizing the experiment conditions, we successfully fabricated high yield of ZnO/Ag nanocomposite with full coverage of high-density polyvinyl chloride (PVC) coating. More importantly, ZnO/Ag nanocomposites were shown to significantly inhibit the growth of S. aureus in solution. It was further shown that ZnO/Ag nanocomposites induced thiol depletion that caused death of S. aureus. The coatings were fully characterized using techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Most importantly, compared to uncoated metals, the coatings on PVC promoted healthy antibacterial activity. Importantly, compared to ZnO-Ag -uncoated PVC, the ZnO/Ag nanocomposites coated was approximately triplet more effective in preventing bacteria attachment. The result of Thermal Gravimetric Analysis (TGA) indicates that, the ZnO/Ag nanocomposites are chemically stable in the temperature range from 50 to 900 ºC. This result, for the first time, demonstrates the potential of using ZnO/Ag nanocomposites as a coating material for numerous anti-bacterial applications.

Keywords: nanocomposites, antibacterial activity, scanning electron microscopy (SEM), x-ray diffraction (XRD)

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1210 Breast Cancer Diagnosing Based on Online Sequential Extreme Learning Machine Approach

Authors: Musatafa Abbas Abbood Albadr, Masri Ayob, Sabrina Tiun, Fahad Taha Al-Dhief, Mohammad Kamrul Hasan

Abstract:

Breast Cancer (BC) is considered one of the most frequent reasons of cancer death in women between 40 to 55 ages. The BC is diagnosed by using digital images of the FNA (Fine Needle Aspirate) for both benign and malignant tumors of the breast mass. Therefore, this work proposes the Online Sequential Extreme Learning Machine (OSELM) algorithm for diagnosing BC by using the tumor features of the breast mass. The current work has used the Wisconsin Diagnosis Breast Cancer (WDBC) dataset, which contains 569 samples (i.e., 357 samples for benign class and 212 samples for malignant class). Further, numerous measurements of assessment were used in order to evaluate the proposed OSELM algorithm, such as specificity, precision, F-measure, accuracy, G-mean, MCC, and recall. According to the outcomes of the experiment, the highest performance of the proposed OSELM was accomplished with 97.66% accuracy, 98.39% recall, 95.31% precision, 97.25% specificity, 96.83% F-measure, 95.00% MCC, and 96.84% G-Mean. The proposed OSELM algorithm demonstrates promising results in diagnosing BC. Besides, the performance of the proposed OSELM algorithm was superior to all its comparatives with respect to the rate of classification.

Keywords: breast cancer, machine learning, online sequential extreme learning machine, artificial intelligence

Procedia PDF Downloads 104
1209 Entrepreneurial Innovation and Challenges of Growth: Perspective from a Developing Economy

Authors: Ibrahim Danjuma, Dahiru Dauda Hammawa

Abstract:

Economic growth and development can be driven by entrepreneurial innovation. The Nigerian economy has faced numerous obstacles over the past few years, including the energy crisis, the death and winding up of many small and medium enterprises, high unemployment rates, and escalating inflation, amongst others. Entrepreneurial innovation has emerged as a potential catalyst for revitalizing the troubled economy and driving sustainable growth. Entrepreneurial innovation can revitalize key industries and foster job creation. This paper proposes significant options as key drivers to entrepreneurial innovation that can take the troubled Nigerian economy out of the woods. It also discusses the significance of government assistance and regulatory actions in fostering entrepreneurial creativity. It argues that initiatives such as funding support, infrastructure development, and regulatory reforms are necessary for fostering a vibrant entrepreneurial ecosystem in Nigeria in order to unlock the full potential of innovative entrepreneurs. Finally, the paper emphasizes the transformative power of entrepreneurial innovation in revamping the troubled Nigerian economy and calls for concerted efforts by all stakeholders to harness its potential for sustainable growth and development. By fostering a culture of innovation, fostering entrepreneurship, and supporting emerging ventures, Nigeria can overcome its economic challenges and pave the way for a prosperous future.

Keywords: entrepreneurial innovation, entrepreneurial ecosystem, troubled economy, Nigeria

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1208 A PROMETHEE-BELIEF Approach for Multi-Criteria Decision Making Problems with Incomplete Information

Authors: H. Moalla, A. Frikha

Abstract:

Multi-criteria decision aid methods consider decision problems where numerous alternatives are evaluated on several criteria. These methods are used to deal with perfect information. However, in practice, it is obvious that this information requirement is too much strict. In fact, the imperfect data provided by more or less reliable decision makers usually affect decision results since any decision is closely linked to the quality and availability of information. In this paper, a PROMETHEE-BELIEF approach is proposed to help multi-criteria decisions based on incomplete information. This approach solves problems with incomplete decision matrix and unknown weights within PROMETHEE method. On the base of belief function theory, our approach first determines the distributions of belief masses based on PROMETHEE’s net flows and then calculates weights. Subsequently, it aggregates the distribution masses associated to each criterion using Murphy’s modified combination rule in order to infer a global belief structure. The final action ranking is obtained via pignistic probability transformation. A case study of real-world application concerning the location of a waste treatment center from healthcare activities with infectious risk in the center of Tunisia is studied to illustrate the detailed process of the BELIEF-PROMETHEE approach.

Keywords: belief function theory, incomplete information, multiple criteria analysis, PROMETHEE method

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1207 Artificial Neural Network for Forecasting of Daily Reservoir Inflow: Case Study of the Kotmale Reservoir in Sri Lanka

Authors: E. U. Dampage, Ovindi D. Bandara, Vinushi S. Waraketiya, Samitha S. R. De Silva, Yasiru S. Gunarathne

Abstract:

The knowledge of water inflow figures is paramount in decision making on the allocation for consumption for numerous purposes; irrigation, hydropower, domestic and industrial usage, and flood control. The understanding of how reservoir inflows are affected by different climatic and hydrological conditions is crucial to enable effective water management and downstream flood control. In this research, we propose a method using a Long Short Term Memory (LSTM) Artificial Neural Network (ANN) to assist the aforesaid decision-making process. The Kotmale reservoir, which is the uppermost reservoir in the Mahaweli reservoir complex in Sri Lanka, was used as the test bed for this research. The ANN uses the runoff in the Kotmale reservoir catchment area and the effect of Sea Surface Temperatures (SST) to make a forecast for seven days ahead. Three types of ANN are tested; Multi-Layer Perceptron (MLP), Convolutional Neural Network (CNN), and LSTM. The extensive field trials and validation endeavors found that the LSTM ANN provides superior performance in the aspects of accuracy and latency.

Keywords: convolutional neural network, CNN, inflow, long short-term memory, LSTM, multi-layer perceptron, MLP, neural network

Procedia PDF Downloads 145
1206 Modified Newton's Iterative Method for Solving System of Nonlinear Equations in Two Variables

Authors: Sara Mahesar, Saleem M. Chandio, Hira Soomro

Abstract:

Nonlinear system of equations in two variables is a system which contains variables of degree greater or equal to two or that comprises of the transcendental functions. Mathematical modeling of numerous physical problems occurs as a system of nonlinear equations. In applied and pure mathematics it is the main dispute to solve a system of nonlinear equations. Numerical techniques mainly used for finding the solution to problems where analytical methods are failed, which leads to the inexact solutions. To find the exact roots or solutions in case of the system of non-linear equations there does not exist any analytical technique. Various methods have been proposed to solve such systems with an improved rate of convergence and accuracy. In this paper, a new scheme is developed for solving system of non-linear equation in two variables. The iterative scheme proposed here is modified form of the conventional Newton’s Method (CN) whose order of convergence is two whereas the order of convergence of the devised technique is three. Furthermore, the detailed error and convergence analysis of the proposed method is also examined. Additionally, various numerical test problems are compared with the results of its counterpart conventional Newton’s Method (CN) which confirms the theoretic consequences of the proposed method.

Keywords: conventional Newton’s method, modified Newton’s method, order of convergence, system of nonlinear equations

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1205 Comparison of Different in vitro Models of the Blood-Brain Barrier for Study of Toxic Effects of Engineered Nanoparticles

Authors: Samir Dekali, David Crouzier

Abstract:

Due to their new physico-chemical properties engineered nanoparticles (ENPs) are increasingly employed in numerous industrial sectors (such as electronics, textile, aerospace, cosmetics, pharmaceuticals, food industry, etc). These new physico-chemical properties can also represent a threat for the human health. Consumers can notably be exposed involuntarily by different routes such as inhalation, ingestion or through the skin. Several studies recently reported a possible biodistribution of these ENPs on the blood-brain barrier (BBB). Consequently, there is a great need for developing BBB in vitro models representative of the in vivo situation and capable of rapidly and accurately assessing ENPs toxic effects and their potential translocation through this barrier. In this study, several in vitro models established with micro-endothelial brain cell lines of different origins (bEnd.3 mouse cell line or a new human cell line) co-cultivated or not with astrocytic cells (C6 rat or C8-B4 mouse cell lines) on Transwells® were compared using different endpoints: trans-endothelial resistance, permeability of the Lucifer yellow and protein junction labeling. Impact of NIST diesel exhaust particles on BBB cell viability is also discussed.

Keywords: nanoparticles, blood-brain barrier, diesel exhaust particles, toxicology

Procedia PDF Downloads 436