Search results for: active and reactive power
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9943

Search results for: active and reactive power

4843 4-Channel CWDM Optical Transceiver Applying Silicon Photonics Ge-Photodiode and MZ-Modulator

Authors: Do-Won Kim, Andy Eu Jin Lim, Raja Muthusamy Kumarasamy, Vishal Vinayak, Jacky Wang Yu-Shun, Jason Liow Tsung Yang, Patrick Lo Guo Qiang

Abstract:

In this study, we demonstrate 4-channel coarse wavelength division multiplexing (CWDM) optical transceiver based on silicon photonics integrated circuits (PIC) of waveguide Ge-photodiode (Ge-PD) and Mach Zehnder (MZ)-modulator. 4-channel arrayed PICs of Ge-PD and MZ-modulator are verified to operate at 25 Gbps/ch achieving 4x25 Gbps of total data rate. 4 bare dies of single-channel commercial electronics ICs (EICs) of trans-impedance amplifier (TIA) for Ge-PD and driver IC for MZ-modulator are packaged with PIC on printed circuit board (PCB) in a chip-on-board (COB) manner. Each single-channel EIC is electrically connected to the one channel of 4-channel PICs by wire bonds to trace. The PICs have 4-channel multiplexer for MZ-modulator and 4-channel demultiplexer for Ge-PD. The 4-channel multiplexer/demultiplexer have echelle gratings for4 CWDM optic signals of which center wavelengths are 1511, 1531, 1553, and 1573 nm. Its insertion loss is around 4dB with over 15dB of extinction ratio.The dimension of 4-channel Ge-PD is 3.6x1.4x0.3mm, and its responsivity is 1A/W with dark current of less than 20 nA.Its measured 3dB bandwidth is around 20GHz. The dimension of the 4-channel MZ-modulator is 3.6x4.8x0.3mm, and its 3dB bandwidth is around 11Ghz at -2V of reverse biasing voltage. It has 2.4V•cmbyVπVL of 6V for π shift to 4 mm length modulator.5x5um of Inversed tapered mode size converter with less than 2dB of coupling loss is used for the coupling of the lensed fiber which has 5um of mode field diameter.The PCB for COB packaging and signal transmission is designed to have 6 layers in the hybrid layer structure. 0.25 mm-thick Rogers Duroid RT5880 is used as the first core dielectric layer for high-speed performance over 25 Gbps. It has 0.017 mm-thick of copper layers and its dielectric constant is 2.2and dissipation factor is 0.0009 at 10 GHz. The dimension of both single ended and differential microstrip transmission lines are calculated using full-wave electromagnetic (EM) field simulator HFSS which RF industry is using most. It showed 3dB bandwidth at around 15GHz in S-parameter measurement using network analyzer. The wire bond length for transmission line and ground connection from EIC is done to have less than 300 µm to minimize the parasitic effect to the system.Single layered capacitors (SLC) of 100pF and 1000pF are connected as close as possible to the EICs for stabilizing the DC biasing voltage by decoupling. Its signal transmission performance is under measurement at 25Gbps achieving 100Gbps by 4chx25Gbps. This work can be applied for the active optical cable (AOC) and quad small form-factor pluggable (QSFP) for high-speed optical interconnections. Its demands are quite large in data centers targeting 100 Gbps, 400 Gbps, and 1 Tbps. As the demands of high-speed AOC and QSFP for the application to intra/inter data centers increase, this silicon photonics based high-speed 4 channel CWDM scheme can have advantages not only in data throughput but also cost effectiveness since it reduces fiber cost dramatically through WDM.

Keywords: active optical cable(AOC), 4-channel coarse wavelength division multiplexing (CWDM), communication system, data center, ge-photodiode, Mach Zehnder (MZ) modulator, optical interconnections, optical transceiver, photonics integrated circuits (PIC), quad small form-factor pluggable (QSFP), silicon photonics

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4842 Electronic Media and Physical Activity of Primary School Children

Authors: Srna Jenko Miholic, Marta Borovec, Josipa Persun

Abstract:

The constant expansion of technology has further accelerated the development of media and vice versa. Although its promotion includes all kinds of interesting and positive sides, the poor functioning of the media is still being researched and proven. Young people, as well as children from the earliest age, resort to the media the most, so it is necessary to defend the role of adults as it were parents, teachers, and environment against virtual co-educators such as the media. The research aim of this study was to determine the time consumption of using electronic media by primary school children as well as their involvement in certain physical activities. Furthermore, to determine what is happening when parents restrict their children's access to electronic media and encourage them to participate in alternative contents during their leisure time. Result reveals a higher percentage of parents restrict their children's access to electronic media and then encourage children to socialize with family and friends, spend time outdoors, engage in physical activity, read books or learn something unrelated to school content even though it would not be children's favorite activity. The results highlight the importance of parental control when it comes to children's use of electronic media and the positive effects that parental control has in terms of encouraging children to be useful, socially desirable, physically active, and healthy activities.

Keywords: elementary school, digital media, leisure time, parents, physical engagement

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4841 Copper Related Toxicity of 1-Hydroxy-2-Thiopyridines

Authors: Elena G. Salina, Vadim A. Makarov

Abstract:

With the emergence of primary resistance to the current drugs and wide distribution of latent tuberculosis infection, a need for new compounds with a novel mode of action is growing steadily. Copper-mediated innate immunity and antibacterial toxicity propose novel strategies in TB drug discovery and development. Transcriptome of M. tuberculosis was obtained by RNA-seq, intracellular copper content was measured by ISP MS and complexes of 1-hydroxy-2-thiopyridines with copper were detected by HPLC.1-hydroxy-2-thiopyridine derivatives were found to be highly active in vitro against both actively growing and dormant non-culturable M. tuberculosis. Transcriptome response to 1-hydroxy-2-thiopyridines revealed signs of copper toxicity in M. tuberculosis bacilli. Indeed, Cu was found to accumulate inside cells treated with 1-hydroxy-2-thiopyridines. These compounds were found to form stable charged lipophylic complexes with Cu²⁺ ions which transport into mycobacterial cell. Subsequent metabolic destruction of the complex led to transformation of 1-hydroxy-2-thiopyridines into 2-methylmercapto-2-ethoxycarbonylpyridines, which did not possess antitubercular activity and releasing of free Cu²⁺ in the cytoplasm. 1-hydroxy-2-thiopyridines are a potent class of Cu-dependent inhibitors of M. tuberculosis which may control M. tuberculosis infection by impairment of copper homeostasis. Acknowledgment: This work was financially supported by the Ministry of Education and Science of the RussianFederation (Agreement No 14.616.21.0065; unique identifier RFMEFI61616X0065).

Keywords: copper toxicity, drug discovery, M. tuberculosis inhibitors, 2-thiopyridines

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4840 Anthropomorphic Brand Mascot Serve as the Vehicle: To Quickly Remind Customers Who You Are and What You Stand for in Indian Cultural Context

Authors: Preeti Yadav, Dandeswar Bisoyi, Debkumar Chakrabati

Abstract:

For many years organization have been exercising a creative technique of applying brand mascots, which results in making a visual ‘ambassador’ of a brand. The goal of mascot’s is just not confined to strengthening the brand identity, improving customer perception, but also acting as a vehicle of anthropomorphic translation towards the consumer. Such that it helps in embracing the power of recognition and processing the experiences happening in our daily lives. The study examines the relationship between the specific mascot features and brand attitude. It eliminates that mascot trust is an important mediator of the mascot features on brand attitude. Anthropomorphic characters turn out to be the key players despite the application of brand mascots in today’s marketing.

Keywords: advertising, mascot, branding, recall

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4839 A Discussion on the Design Practice of College Students for Virtual Avatars in Social Media Ecology

Authors: Mei-Chun Chang

Abstract:

Due to digital transformation and social media development in recent years, various real-time interactive digital tools have been developed to meet the design demands for virtual reality avatars, which also promote digital content learners' active participation in the creation process. As a result, new social media design tools have the characteristics of intuitive operation with a simplified interface for fast production, from which works can be simply created. This study carried out observations, records, questionnaire surveys, and interviews on the creation and learning of visual avatars made by students of the National Taiwan University of Science and Technology (NTUST) with the VRoid Studio 3D modeling tool so as to explore their learning effectiveness on the design of visual avatars. According to the results of this study, the VRoid Studio 3D character modeling tool has a positive impact on the learners and helps to improve their learning effectiveness. Students with low academic achievements said that they could complete the conceived modeling with their own thinking by using the design tool, which increased their sense of accomplishment. Conclusions are drawn according to the results, and relevant future suggestions are put forward.

Keywords: virtual avatar, character design, social media, vroid studio, creation, digital learning

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4838 Upsouth: Digitally Empowering Rangatahi (Youth) and Whaanau (Families) to Build Skills in Critical and Creative Thinking to Achieve More Active Citizenship in Aotearoa New Zealand

Authors: Ayla Hoeta

Abstract:

In a post-colonial Aotearoa New Zealand, solutions by rangatahi (youth) for rangatahi are essential as is civic participation and building economic agency in an increasingly tough economic climate. Upsouth was an online community crowdsourcing platform developed by The Southern Initiative, in collaboration with Itsnoon that provides rangatahi and whānau (family) a safe space to share lived experience, thoughts and ideas about local kaupapa (issues/topics) of importance to them. The target participants were Māori indigenous peoples and Pacifica groups, aged 14 - 21 years. In the Aotearoa New Zealand context, this participant group is not likely to engage in traditional consultation processes despite being an essential constituent in helping shape better local communities, whānau and futures. The Upsouth platform was active for two years from 2018-2019 where it completed 42 callups with 4300+ participants. The web platform collates the ideas, voices, feedback, and content of users around a callup that has been commissioned by a sponsor, such as Auckland Council, Z Energy or Auckland Transport. A callup may be about a pressing challenge in a community such as climate change, a new housing development, homelessness etc. Each callup was funded by the sponsor with Upsouths main point of difference being that participants are given koha (money donation) through digital wallets for their ideas. Depending on the quality of what participants upload, the koha varies between small micropayments and larger payments. This encouraged participants to develop creative and critical thinking - upskilling for future focussed jobs, enterprise and democratic skills while earning pocket money at the same time. Upsouth enables youth-led action and voice, and empowers them to be a part of a reciprocal and creative economy. Rangatahi are encouraged to express themselves culturally, creatively, freely and in a way they are free to choose - for example, spoken word, song, dance, video, drawings, and/or poems. This challenges and changes what is considered acceptable as community engagement feedback by the local government. Many traditional engagement platforms are not as consultative, do not accept diverse types of feedback, nor incentivise this valuable expression of feedback. Upsouth is also empowering for rangatahi, since it allows them the opportunity to express their opinions directly to the government. Upsouth gained national and international recognition for the way it engages with youth: winning the Supreme Award and the Accessibility and Transparency Award at Auckland Council’s 2018 Engagement Awards, becoming a finalist in the 2018 Digital Equity and Accessibility category of International Data Corporation’s Smart City Asia and Pacific Awards. This paper will fully contextualize the challenges of rangatahi and whānau civic engagement in Aotearoa New Zealand and then present a reflective case study of the Upsouth project, with examples from some of the callups. This is intended to form part of the Divided Cities 22 conference New Ground sub-theme as a critical reflection on a design intervention, which was conceived and implemented by the lead author to overcome the post-colonial divisions of Māori, Pacifica and minority ethnic rangatahi in Aotearoa New Zealand.

Keywords: rangatahi, youth empowerment, civic engagement, enabling, relating, digital platform, participation

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4837 Investigating the Effect of the Flipped Classroom Using E-Learning on Language Proficiency, Learner's Autonomy, and Class Participation of English Language Learners

Authors: Michelle Siao-Cing Guo

Abstract:

Technology is widely adopted to assist instruction and learning across disciplines. Traditional teaching method fails to capture the attention of the generation of digital native and does not accommodate diverse needs of today’s learners. The innovation in technology allows new pedagogical approaches. One approach that converts the traditional learning classroom to a more flexible learning time and space is known as the flipped classroom. This new pedagogy extends and enhances learning and accommodates different learning styles. The flipped classroom employs technology to offer course materials online 24 hours/day and to promote active class learning. However, will Taiwanese students who are used to more traditional instructional methods embrace the flipped classroom using E-learning? Will the flipped approach have an effect on Taiwanese students’ English mastery and learning autonomy? The researcher compares a flipped classroom model using E-learning and the traditional-lecture model. A pre- and post-test and a questionnaire were utilized to examine the effect of the flipped classroom on Taiwanese college students. The test results showed that the flipped approach had a positive effect on learners’ English proficiency level, topical knowledge, and willingness to participate in class. The questionnaire also demonstrates the acceptance of the new teaching model.

Keywords: flipped classroom , E-learning, innovative teaching, technology

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4836 Design of Functional Safe Motor Control Systems in Automotive Applications

Authors: Jae-Woo Kim, Kyung-Jung Lee, Hyun-Sik Ahn

Abstract:

This paper presents a design methodology for the motor driven automotive subsystems with the consideration of the functional safety. There are many such modules in vehicles which use DC/AC motors for an electronic throttle control system, a motor driven power steering, a motor driven seat belt systems and for HVAC systems. The functional safety for the automotive electrical and electronic parts are standardized as ISO 26262, but the development procedure is very complex to be followed. We focus on the functional safe motor controller design process and show the designed motor controller hardware satisfies the required safety integrity level by using metric calculations with the safety mechanism.

Keywords: AUTOSAR, MDPS, Simulink, software component

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4835 Analyzing Soviet and Post-Soviet Contemporary Russian Foreign Policy by Applying the Theory of Political Realism

Authors: Simon Tsipis

Abstract:

In this study, we propose to analyze Russian foreign policy conduct by applying the theory of Political Realism and the qualitative comparative method of analysis. We find that the paradigm of Political Realism supplies us with significant insights into the sources of contemporary Russian foreign policy conduct since the power factor was and remains an integral element in Russian foreign policies, especially when we apply comparative analysis and compare it with the behavior of its Soviet predecessor. Through the lens of the Realist theory, a handful of Russian foreign policy-making becomes clearer and much more comprehensible.

Keywords: realism, Russia, cold war, Soviet Union, European security

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4834 Denoising of Motor Unit Action Potential Based on Tunable Band-Pass Filter

Authors: Khalida S. Rijab, Mohammed E. Safi, Ayad A. Ibrahim

Abstract:

When electrical electrodes are mounted on the skin surface of the muscle, a signal is detected when a skeletal muscle undergoes contraction; the signal is known as surface electromyographic signal (EMG). This signal has a noise-like interference pattern resulting from the temporal and spatial summation of action potentials (AP) of all active motor units (MU) near electrode detection. By appropriate processing (Decomposition), the surface EMG signal may be used to give an estimate of motor unit action potential. In this work, a denoising technique is applied to the MUAP signals extracted from the spatial filter (IB2). A set of signals from a non-invasive two-dimensional grid of 16 electrodes from different types of subjects, muscles, and sex are recorded. These signals will acquire noise during recording and detection. A digital fourth order band- pass Butterworth filter is used for denoising, with a tuned band-pass frequency of suitable choice of cutoff frequencies is investigated, with the aim of obtaining a suitable band pass frequency. Results show an improvement of (1-3 dB) in the signal to noise ratio (SNR) have been achieved, relative to the raw spatial filter output signals for all cases that were under investigation. Furthermore, the research’s goal included also estimation and reconstruction of the mean shape of the MUAP.

Keywords: EMG, Motor Unit, Digital Filter, Denoising

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4833 Multi-Tooled Robotic Hand for Tele-Operation of Explosive Devices

Authors: Faik Derya Ince, Ugur Topgul, Alp Gunay, Can Bayoglu, Dante J. Dorantes-Gonzalez

Abstract:

Explosive attacks are arguably the most lethal threat that may occur in terrorist attacks. In order to counteract this issue, explosive ordnance disposal operators put their lives on the line to dispose of a possible improvised explosive device. Robots can make the disposal process more accurately and saving human lives. For this purpose, there is a demand for more accurate and dexterous manipulating robotic hands that can be teleoperated from a distance. The aim of this project is to design a robotic hand that contains two active and two passive DOF for each finger, as well as a minimum set of tools for mechanical cutting and screw driving within the same robotic hand. Both hand and toolset, are teleoperated from a distance from a haptic robotic glove in order to manipulate dangerous objects such as improvised explosive devices. SolidWorks® Computer-Aided Design, computerized dynamic simulation, and MATLAB® kinematic and static analysis were used for the robotic hand and toolset design. Novel, dexterous and robust solutions for the fingers were obtained, and six servo motors are used in total to remotely control the multi-tooled robotic hand. This project is still undergoing and presents currents results. Future research steps are also presented.

Keywords: Explosive Manipulation, Robotic Hand, Tele-Operation, Tool Integration

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4832 Servitization in Machine and Plant Engineering: Leveraging Generative AI for Effective Product Portfolio Management Amidst Disruptive Innovations

Authors: Till Gramberg

Abstract:

In the dynamic world of machine and plant engineering, stagnation in the growth of new product sales compels companies to reconsider their business models. The increasing shift toward service orientation, known as "servitization," along with challenges posed by digitalization and sustainability, necessitates an adaptation of product portfolio management (PPM). Against this backdrop, this study investigates the current challenges and requirements of PPM in this industrial context and develops a framework for the application of generative artificial intelligence (AI) to enhance agility and efficiency in PPM processes. The research approach of this study is based on a mixed-method design. Initially, qualitative interviews with industry experts were conducted to gain a deep understanding of the specific challenges and requirements in PPM. These interviews were analyzed using the Gioia method, painting a detailed picture of the existing issues and needs within the sector. This was complemented by a quantitative online survey. The combination of qualitative and quantitative research enabled a comprehensive understanding of the current challenges in the practical application of machine and plant engineering PPM. Based on these insights, a specific framework for the application of generative AI in PPM was developed. This framework aims to assist companies in implementing faster and more agile processes, systematically integrating dynamic requirements from trends such as digitalization and sustainability into their PPM process. Utilizing generative AI technologies, companies can more quickly identify and respond to trends and market changes, allowing for a more efficient and targeted adaptation of the product portfolio. The study emphasizes the importance of an agile and reactive approach to PPM in a rapidly changing environment. It demonstrates how generative AI can serve as a powerful tool to manage the complexity of a diversified and continually evolving product portfolio. The developed framework offers practical guidelines and strategies for companies to improve their PPM processes by leveraging the latest technological advancements while maintaining ecological and social responsibility. This paper significantly contributes to deepening the understanding of the application of generative AI in PPM and provides a framework for companies to manage their product portfolios more effectively and adapt to changing market conditions. The findings underscore the relevance of continuous adaptation and innovation in PPM strategies and demonstrate the potential of generative AI for proactive and future-oriented business management.

Keywords: servitization, product portfolio management, generative AI, disruptive innovation, machine and plant engineering

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4831 Optimal Voltage and Frequency Control of a Microgrid Using the Harmony Search Algorithm

Authors: Hossein Abbasi

Abstract:

The stability is an important topic to plan and manage the energy in the microgrids as the same as the conventional power systems. The voltage and frequency stability is one of the most important issues recently studied in microgrids. The objectives of this paper are the modelling and designing of the components and optimal controllers for the voltage and frequency control of the AC/DC hybrid microgrid under the different disturbances. Since the PI controllers have the advantages of simple structure and easy implementation, so they are designed and modeled in this paper. The harmony search (HS) algorithm is used to optimize the controllers’ parameters. According to the achieved results, the PI controllers have a good performance in voltage and frequency control of the microgrid.

Keywords: frequency control, HS algorithm, microgrid, PI controller, voltage control

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4830 Impact of Harmonic Resonance and V-THD in Sohar Industrial Port–C Substation

Authors: R. S. Al Abri, M. H. Albadi, M. H. Al Abri, U. K. Al Rasbi, M. H. Al Hasni, S. M. Al Shidi

Abstract:

This paper presents an analysis study on the impacts of the changes of the capacitor banks, the loss of a transformer, and the installation of distributed generation on the voltage total harmonic distortion and harmonic resonance. The study is applied in a real system in Oman, Sohar Industrial Port–C Substation Network. Frequency scan method and Fourier series analysis method are used with the help of EDSA software. Moreover, the results are compared with limits specified by national Oman distribution code.

Keywords: power quality, capacitor bank, voltage total harmonics distortion, harmonic resonance, frequency scan

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4829 Advancing UAV Operations with Hybrid Mobile Network and LoRa Communications

Authors: Annika J. Meyer, Tom Piechotta

Abstract:

Unmanned Aerial Vehicles (UAVs) have increasingly become vital tools in various applications, including surveillance, search and rescue, and environmental monitoring. One common approach to ensure redundant communication systems when flying beyond visual line of sight is for UAVs to employ multiple mobile data modems by different providers. Although widely adopted, this approach suffers from several drawbacks, such as high costs, added weight and potential increases in signal interference. In light of these challenges, this paper proposes a communication framework intermeshing mobile networks and LoRa (Long Range) technology—a low-power, long-range communication protocol. LoRaWAN (Long Range Wide Area Network) is commonly used in Internet of Things applications, relying on stationary gateways and Internet connectivity. This paper, however, utilizes the underlying LoRa protocol, taking advantage of the protocol’s low power and long-range capabilities while ensuring efficiency and reliability. Conducted in collaboration with the Potsdam Fire Department, the implementation of mobile network technology in combination with the LoRa protocol in small UAVs (take-off weight < 0.4 kg), specifically designed for search and rescue and area monitoring missions, is explored. This research aims to test the viability of LoRa as an additional redundant communication system during UAV flights as well as its intermeshing with the primary, mobile network-based controller. The methodology focuses on direct UAV-to-UAV and UAV-to-ground communications, employing different spreading factors optimized for specific operational scenarios—short-range for UAV-to-UAV interactions and long-range for UAV-to-ground commands. This explored use case also dramatically reduces one of the major drawbacks of LoRa communication systems, as a line of sight between the modules is necessary for reliable data transfer. Something that UAVs are uniquely suited to provide, especially when deployed as a swarm. Additionally, swarm deployment may enable UAVs that have lost contact with their primary network to reestablish their connection through another, better-situated UAV. The experimental setup involves multiple phases of testing, starting with controlled environments to assess basic communication capabilities and gradually advancing to complex scenarios involving multiple UAVs. Such a staged approach allows for meticulous adjustment of parameters and optimization of the communication protocols to ensure reliability and effectiveness. Furthermore, due to the close partnership with the Fire Department, the real-world applicability of the communication system is assured. The expected outcomes of this paper include a detailed analysis of LoRa's performance as a communication tool for UAVs, focusing on aspects such as signal integrity, range, and reliability under different environmental conditions. Additionally, the paper seeks to demonstrate the cost-effectiveness and operational efficiency of using a single type of communication technology that reduces UAV payload and power consumption. By shifting from traditional cellular network communications to a more robust and versatile cellular and LoRa-based system, this research has the potential to significantly enhance UAV capabilities, especially in critical applications where reliability is paramount. The success of this paper could pave the way for broader adoption of LoRa in UAV communications, setting a new standard for UAV operational communication frameworks.

Keywords: LoRa communication protocol, mobile network communication, UAV communication systems, search and rescue operations

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4828 Identification of Active Phytocomponents in the Ethyl Acetate Extract of Glycosmis pentaphylla Retz. DC by Using GC-MS

Authors: M. Sivakumar, D. Chamundeeswari

Abstract:

Glycosmis pentaphylla is one of the medicinally important plants belonging to the family Rutaceae, commonly known as “Anam or Panal” in Tamil. Traditionally, leaves are useful in fever, hepatopathy, eczema, skin disease, helminthiasis, wounds, and erysipelas. The fruits are sweet and are useful in vitiated conditions of vata, kapha, cough, and bronchitis. The roots are good for facial inflammations, rheumatism, jaundice, and anemia. The preliminary phytochemical investigations indicated the presence of alkaloids, terpenoids, flavonoids, tannins, sugar, glycoside, and phenolic compounds. In the present study, the root part of Glycosmis pentaphylla was used, and the root was collected from Western Ghats of South India. The root was sun/shade dried and pulverized to powder in a mechanical grinder. The powder was successively extracted with various solvents, and the ethyl acetate extract of Glycosmis pentaphylla has been subjected to the GC-MS analysis. Amongst the 46 chemical constituents identified from this plant, three major phytoconstituents were reported for the first time. Marmesin, a furanocumarin compound with the chemical structure 7H-Furo (3,2-G) (1)Benzopyran-7-one,2,3–dihydro–2 - (1-Hydroxy-1methylethyl)-(s) is one of the three compounds identified for the first time at the concentration of 11-60% in ethyl acetate extract of Glycosmis pentaphylla. Others include, Beta.-Fagarine (4.71%) and Paverine (13.08%).

Keywords: ethyl acetate extract, Glycosmis pentaphylla, GC-MS analysis, Phytochemicals

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4827 Comparison of Cardiometabolic Risk Factors in Lean Versus Overweight/Obese Peri-Urban Female Adolescent School Learners in Mthatha, South Africa: A Pilot Case Control Study

Authors: Benedicta N. Nkeh-Chungag, Constance R. Sewani-Rusike, Isaac M. Malema, Daniel T. Goon, Oladele V. Adeniyi, Idowu A. Ajayi

Abstract:

Background: Childhood and adolescent obesity is an important predictor of adult cardiometabolic diseases. Current data on age- and gender-specific cardiometabolic risk factors are lacking in the peri-urban Eastern Cape Province, South Africa. However, such information is important in designing innovative strategies to promote healthy living among children and adolescents. The purpose of this pilot study was to compare and determine the extent of cardiometabolic risk factors between samples of lean and overweight/obese adolescent population in a peri-urban township of South Africa. Methods: In this case-control study, age-matched, non-pregnant and non-lactating female adolescents consisting of equal number of cases (50 overweight/obese) and control (50 lean) participated in the study. Fasting venous blood samples were obtained for total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (Trig), highly sensitive C-reactive protein (hsCRP) and blood sugar. Anthropometric measurements included weight, height, waist and hip circumferences. Body mass index was calculated. Blood pressure was measured; and metabolic syndrome was assessed using appropriate diagnostic criteria for children and adolescents. Results: Of the 76 participants with complete data, 12/38 of the overweight/obese and 1/38 of the lean group met the criteria for adolescent metabolic syndrome. All cardiometabolic risk factors were elevated in the overweight/obese group compared with the lean group: low HDL-C (RR = 2.21), elevated TC (RR = 1.23), elevated LDL-C (RR = 1.42), elevated Trig (RR = 1.73), and elevated hsCRP (RR = 1.9). There were significant atherosclerotic indices among the overweight/obese group compared with the lean group: TC/HDL and LDL/HDL (2.99±0.91 vs 2.63±0.48; p=0.016 and 1.73±0.61 vs 1.41±0.46; p= 0.014, respectively). Conclusion: There are multiple cardiometabolic risk factors among the overweight/obese female adolescent group compared with lean adolescent group in the study. Female adolescent who are overweight and obese have higher relative risks of developing cardiometabolic diseases compared with their lean counterparts in the peri-urban Mthatha, South Africa. School health programme focusing on promoting physical exercise, healthy eating and keeping appropriate weight are needed in the country.

Keywords: adolescents, cardiometabolic risk factors, obesity, peri-urban South Africa

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4826 Achieving Product Robustness through Variation Simulation: An Industrial Case Study

Authors: Narendra Akhadkar, Philippe Delcambre

Abstract:

In power protection and control products, assembly process variations due to the individual parts manufactured from single or multi-cavity tooling is a major problem. The dimensional and geometrical variations on the individual parts, in the form of manufacturing tolerances and assembly tolerances, are sources of clearance in the kinematic joints, polarization effect in the joints, and tolerance stack-up. All these variations adversely affect the quality of product, functionality, cost, and time-to-market. Variation simulation analysis may be used in the early product design stage to predict such uncertainties. Usually, variations exist in both manufacturing processes and materials. In the tolerance analysis, the effect of the dimensional and geometrical variations of the individual parts on the functional characteristics (conditions) of the final assembled products are studied. A functional characteristic of the product may be affected by a set of interrelated dimensions (functional parameters) that usually form a geometrical closure in a 3D chain. In power protection and control products, the prerequisite is: when a fault occurs in the electrical network, the product must respond quickly to react and break the circuit to clear the fault. Usually, the response time is in milliseconds. Any failure in clearing the fault may result in severe damage to the equipment or network, and human safety is at stake. In this article, we have investigated two important functional characteristics that are associated with the robust performance of the product. It is demonstrated that the experimental data obtained at the Schneider Electric Laboratory prove the very good prediction capabilities of the variation simulation performed using CETOL (tolerance analysis software) in an industrial context. Especially, this study allows design engineers to better understand the critical parts in the product that needs to be manufactured with good, capable tolerances. On the contrary, some parts are not critical for the functional characteristics (conditions) of the product and may lead to some reduction of the manufacturing cost, ensuring robust performance. The capable tolerancing is one of the most important aspects in product and manufacturing process design. In the case of miniature circuit breaker (MCB), the product's quality and its robustness are mainly impacted by two aspects: (1) allocation of design tolerances between the components of a mechanical assembly and (2) manufacturing tolerances in the intermediate machining steps of component fabrication.

Keywords: geometrical variation, product robustness, tolerance analysis, variation simulation

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4825 Early Vasopressor and De-resuscitation in Steven Johnson Syndrome with Septic Shock: A Case Report

Authors: Darma Putra Sitepu, Dewi Larasati, Yohanes Wolter Hendrik George

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Sepsis is a life-threatening medical emergency frequently observed in intensive care unit (ICU). Surviving Sepsis Campaign in 2018 has recommended the administration of early vasopressor in the first hour of sepsis or septic shock but has not yet included de-resuscitation protocol. De-resuscitation in acute management of septic shock is where patient received active removal of accumulated fluid. It has been proposed by some studies and ongoing clinical trials. Here we present a case with early vasopressor and de-resuscitation. Male, 27 years old presenting to the emergency room with shortness of breath, altered mental status, and widespread blisters on his body and lips started a few hours prior, after receiving non-steroidal anti-inflammatory drug through intravenous injection. Patient was hypotensive, tachycardic, and tachypneic at admission, diagnosed with Steven Johnson Syndrome with Septic Shock. Patient received fluid resuscitation, early vasopressor, and diuresis agent aimed to actively remove fluid after the initial phase of resuscitation. Patient was admitted to ICU and progressively recovering. At day-10, patient was stabilized and was transferred to general ward. Early vasopressor and de-resuscitation are beneficial for the patient.

Keywords: sepsis, shock, de-resuscitation, vasopressor, fluid, case report

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4824 Implementing Service Innovation in Public Transport Sector: Drivers and Challenges

Authors: Chaoren Lu

Abstract:

Public policy is playing as one driving force that influencing service innovation implementation in public sector. However, public policy implications cannot be automatically derived from the analyses of innovation issues, and there lacks of researches about the influences of public policy onto innovation. Moreover, innovation in service system is hard to predictable and whether policy encourages or hidden innovation is still lack of study. Especially, by given the context that multiple actors are active involving within the service delivery process in public transport sector, the complex driving forces and challenges are emerged towards the service operation. This study is aim to analysis the service innovation practices within service operating organizations to understand the drivers and challenges of service operation based on policy requirements, and where the innovation idea generating from. The case studies of Changzhou Transit Group and Nanjing Jiangnan Public Transit Group will be launched. This paper reveals the ambidexterity between top-down and bottom-up demands within the public transport service operating organizations contribute to the innovation ideas. Meanwhile, it contributes to the understanding of fundamental elements of service innovation is the new relationship creation and new way of sharing knowledge. The policy contributes to the trigger of creation of such relationship. The research question is: what are the sources of service innovation practices in local public transport system in China in in facing the policy implementation?

Keywords: public value, service innovation, public transport service, China

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4823 Conceptualization and Strategies of Biogas Technology for Rural Development in Nigeria

Authors: Okorowo Cyril Agochi

Abstract:

The main challenge of present world is to harness the energy source which is environment friendly and ecologically balanced. This need has forced to search for other alternate source of energy. But unfortunately the new alternative energy sources like the solar, hydro, wind etc. require huge economical value and technical power to operate, which seem to be very difficult for the developing countries like Nigeria. In the present moment biogas energy can be one and only reliable, easily available and economically feasible source of alternative and renewable source which can be managed by locally available sources and simple technology for secondary schools, tertiary institution and rural villages. This paper is aimed at boosting the energy generation for developing of rural Nigeria, through Biogas.

Keywords: bio-gas, energy, environment, nigeria, technology

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4822 Chemopreventive Potency of Medicinal and Eatable Plant, Gromwell Seed on in Vitro and in Vivo Carcinogenesis Systems

Authors: Harukuni Tokuda, Xu FengHao, Nobutaka Suzuki

Abstract:

As part of an ongoing our projects to investigate the anti-tumor promoring properties (chemopreventive potency) of Gromwell seed, dry powder materials and its active compounds were carried out through useful test systems. Gromwell seed (Coix lachryma-jobi seed) (GS) is a grass crop that has long been used and played a role in traditional medicine as a nourishing food, and for the treatment of various aliments, paticularly cancer. The application of a new screening procedure which utilizes the synergistic effect of short-chain fatty acids and phorbol esters in enable rapid and easy detection of naturally occurring substances(anti-tumor promoters chemo-preventive agents) with inhibition of Epstein-Barr virus(EBV) activation, using human lymphblastoid cells. In addition, we have now extended these investigations to a new tumorigenesis model in which we initiated the tumors with DMBA intiation and promoted with 1.7 nmol of TPA in two-stage mouse skin test and other models. these results provide a basis for further development of these botanical supplements for human cancer chemoprevention and observations seem that this materials more extensively as one of the trials for the purpose of complementary and alternative medicine.

Keywords: chemoprevention, medicinal plant, mouse, carcinogenesis systems

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4821 Structural Alteration of MoS₂ by Incorporating Fe, Co Composite for an Enhanced Oxygen Evolution Reaction

Authors: Krishnamoorthy Sathiyan, Shanti Gopal Patra, Ronen Bar-Ziv, Tomer Zidki

Abstract:

Developing efficient non-noble metal catalysts that are cheap and durable for oxygen evolution reaction (OER) is a great challenge. Moreover, altering the electronic structure of the catalyst and structural engineering of the materials provide a new direction for enhancing the OER. Herein, we have successfully synthesized Fe and Co incorporated MoS₂ catalysts, which show improved catalytic activity for OER when compared with MoS₂, Fe-MoS₂, and Co-MoS₂. It was found that at an optimal ratio of Fe and Co, the electronic and structural modification of MoS₂ occurs, which leads to change in orientation and thereby enhances the active catalytic sites on the edges, which are more exposed for OER. The nanocomposites have been well characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive X-ray analysis (EDX), Elemental Mapping, transmission electron microscope (TEM), and high-resolution transmission electron microscope (HR-TEM) analysis. Among all, a particular ratio of FeCo-MoS₂ exhibits a much smaller onset with better catalytic current density. The remarkable catalytic activity is mainly attributed to the synergistic effect from the Fe and Co. Most importantly, our work provides an essential insight in altering the electronic structure of MoS₂ based materials by incorporating promoters such as Co and Fe in an optimal amount, which enhances OER activity.

Keywords: electrocatalysts, molybdenum disulfide, oxygen evolution reaction, transition metals

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4820 Improvement of Fatigue and Fatigue Corrosion Resistances of Turbine Blades Using Laser Cladding

Authors: Sami I. Jafar, Sami A. Ajeel, Zaman A. Abdulwahab

Abstract:

The turbine blades used in electric power plants are made of low alloy steel type 52. These blades will be subjected to fatigue and also at other times to fatigue corrosion with aging time. Due to their continuous exposure to cyclic rotational stresses in corrosive steam environments, The current research aims to deal with this problem using the laser cladding method for low alloy steel type 52, which works to re-compose the metallurgical structure and improve the mechanical properties by strengthening the resulting structure, which leads to an increase in fatigue and wears resistance, therefore, an increase in the life of these blades is observed.

Keywords: fatigue, fatigue corrosion, turbine blades, laser cladding

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4819 Effect of Hydrogen Peroxide Concentration Produced by Cold Atmospheric Plasma on Inactivation of Escherichia Coli in Water

Authors: Zohreh Rashmei

Abstract:

Introduction: Plasma inactivation is one of the emerging technologies in biomedical field and has been applied to the inactivation of microorganisms in water. The inactivation effect has been attributed to the presence of active plasma species, i.e. OH, O, O3, H2O2, UV and electric fields, generated by the discharge of plasma. Material and Method: To evaluate germicidal effects of plasma, the electric spark discharge device was used. After the effect of the plasma samples were collected for culture medium agar plate count. In addition to biological experiments, the concentration of hydrogen peroxide was also measured. Results: The results showed that Plasma is able to inactivate a high concentration of E. coli. After a short period of plasma radiation on the surface of water, the amount log8 reduced the microbial load. Starting plasma radiation on the surface of the water, the measurements show of production and increasing the amount of hydrogen peroxide in water. So that at the end of the experiment, the concentration of hydrogen peroxide to about 100 mg / l increased. Conclusion: Increasing the concentration of hydrogen peroxide is directly related to the reduction of microbial load. The results of E. coli culture in media containing certain concentrations of H2O2 showed that E. coli can not to grow in a medium containing more than 2/5 mg/l of H2O2. Surely we can say that the main cause of killing bacteria is a molecule of H2O2.

Keywords: plasma, hydrogen peroxide, disinfection, E. coli

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4818 Liquefaction Susceptibility of Tailing Storage Facility-Comparison of National Centre for Earthquake Engineering Research and Finite Element Methods

Authors: Mehdi Ghatei, Masoomeh Lorestani

Abstract:

Upstream Tailings Storage Facilities (TSFs) may experience slope instabilities due to soil liquefaction, especially in regions known to be seismically active. In this study, liquefaction susceptibility of an upstream-raised TSF in Western Australia was assessed using two different approaches. The first approach assessed liquefaction susceptibility using Cone Penetration Tests with pore pressure measurement (CPTu) as described by the National Centre for Earthquake Engineering Research (NCEER). This assessment was based on the four CPTu tests that were conducted on the perimeter embankment of the TSF. The second approach used the Finite Element (FE) method with application of an equivalent linear model to predict the undrained cyclic behavior, the pore water pressure and the liquefaction of the materials. The tailings parameters were estimated from the CPTu profiles and from the laboratory tests. The cyclic parameters were estimated from the literature where test results of similar material were available. The results showed that there was a good agreement, in the liquefaction susceptibility of the tailings material, between the NCEER and FE methods with equivalent linear model.

Keywords: liquefaction , CPTU, NCEER, finite element method, equivalent linear model

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4817 An Antifungal Peptide from Actinobacteria (Streptomyces Sp. TKJ2): Isolation and Partial Characterization

Authors: Abdelaziz Messis, Azzeddine Bettache, Nawel Boucherba, Said Benallaoua, Mouloud Kecha

Abstract:

Actinobacteria are of special biotechnological interest since they are known to produce chemically diverse compounds with a wide range of biological activity. This distinct clade of Gram-positve bacteria include some of the key antibiotic producers and are also sources of several bioactive compounds, established commercially a newly filamentous bacteria was recovered from Tikjda forest soil (Algeria) for its high antifungal activity against various pathogenic and phytopathogenic fungi. The nucleotide sequence of the 16S rRNA gene (1454 pb) of Streptomyces sp. TKJ2 exhibited close similarity (99 %) with other Streptomyces16S rRNA genes. Antifungal metabolite production of Streptomyces sp TKJ2 was evaluated using six different fermentation media. The extracellular products contained potent antifungal agents. Antifungal protein produced by Streptomyces sp. TKJ2 on PCA medium has been purified by ammonium sulfate precipitation, SPE column chromatography and high-performance liquid chromatography in a reverse-phase column. The UV chromatograms of the active fractions obtained at 214 nm by NanoLC-ESI-MS/MS have different molecular weights. The F20 Peptidic fraction obtained from culture filtrat of Streptomyces sp. TKJ2 precipitated at 30% of ammonium sulfate was selected for analysis by infusion ESI-MS which yielded a singly charged ion mass of 437.17 Da.

Keywords: actinobacteria, antifungal protein, chromatography, Streptomyces

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4816 Analysis of Syngas Combustion Characteristics in Can-Type Combustor using CFD

Authors: Norhaslina Mat Zian, Hasril Hasini, Nur Irmawati Om

Abstract:

This study focuses on the flow and combustion behavior inside gas turbine combustor used in thermal power plant. The combustion process takes place using synthetic gas and the baseline solution was made on gas turbine combustor firing natural gas (100% Methane) as the main source of fuel. Attention is given to the effect of the H2/CO ratio on the variation of the flame profile, temperature distribution, and emissions. The H2/CO ratio varies in the range of 10-80 % and the CH4 values are fixed 10% for each case. While keeping constant the mass flow rate and operating pressure, the preliminary result shows that the flow inside the can-combustor is highly swirling which indicates good mixing of fuel and air prior to the entrance of the mixture to the main combustion zone.

Keywords: cfd, combustion, flame, syngas

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4815 Energy Detection Based Sensing and Primary User Traffic Classification for Cognitive Radio

Authors: Urvee B. Trivedi, U. D. Dalal

Abstract:

As wireless communication services grow quickly; the seriousness of spectrum utilization has been on the rise gradually. An emerging technology, cognitive radio has come out to solve today’s spectrum scarcity problem. To support the spectrum reuse functionality, secondary users are required to sense the radio frequency environment, and once the primary users are found to be active, the secondary users are required to vacate the channel within a certain amount of time. Therefore, spectrum sensing is of significant importance. Once sensing is done, different prediction rules apply to classify the traffic pattern of primary user. Primary user follows two types of traffic patterns: periodic and stochastic ON-OFF patterns. A cognitive radio can learn the patterns in different channels over time. Two types of classification methods are discussed in this paper, by considering edge detection and by using autocorrelation function. Edge detection method has a high accuracy but it cannot tolerate sensing errors. Autocorrelation-based classification is applicable in the real environment as it can tolerate some amount of sensing errors.

Keywords: cognitive radio (CR), probability of detection (PD), probability of false alarm (PF), primary user (PU), secondary user (SU), fast Fourier transform (FFT), signal to noise ratio (SNR)

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4814 Rethinking Propaganda Discourse: Convergence and Divergence Unveiled

Authors: Mandy Tao Benec

Abstract:

Propaganda, understood as a ‘deliberate attempt to persuade people to think and behave in a desired way’, contributes to the fabric of mass media discourse as an important component, albeit often under various alternative expressions except ‘propaganda’. When the word ‘propaganda’ does appear in the mainstream media of the West, it is often selectively applied upon undesiring parties such as China, the North Korea, Russia’s Putin, or terrorists, etc.. This attitude reveals an ‘us verse them’ mentality; and a presupposition that propaganda is something only ‘they’ do whilst ‘we’ do not. This phenomenon not only runs in danger of generating political naivety, but also calls for the necessity of re-examining propaganda which will benefit from analysing it in contrasting social and political environments. Therefore, this paper aims to compare how propaganda has been understood and put in practice both in the Anglo-American context and by the Chinese Communist Party (CCP). By revealing the convergence and divergence of the propaganda discourses between China and the West, it will help clarify the misconception and misunderstanding of the term. Historical narrative analysis and critical discourse analysis are the main methodologies. By carefully examining data from academic research on propaganda in both English and Chinese, the landscape of how propaganda is defined throughout different eras is mapped, with special attention paid to analysing the parallelism and/or correspondence between China and the West when applicable. Meanwhile, critically analysing the official documents such as speeches and guidelines for propaganda administration given by top-rank CCP leaders will help reveal that in contrast to the West’s ‘us-them’ mentality, China sees oneself in no difference with the Western democracies when propaganda is concerned. Major findings of this study will identify a series of convergence and divergence between Chinese and Western propaganda discourses, and the relationship between propaganda the ‘signified’ (its essence) and propaganda the ‘signifier’ (the term itself), including (yet not limited to): 1) convergence in China catching up with the West, acknowledging the perceived pejorative connotation of the term 2) divergence in propaganda activities disassociated from the term in the West; and convergence in adopting such practice when China following suit in its external propaganda towards the West 3) convergence in utilising alternative notions to replace ‘propaganda’, first by the West, then imported and incorporated enthusiastically by China into its propaganda discourse 4) divergence between China’s internal and external propaganda and the subsequent differentiation between in which contexts the CCP sees fit to utilise the concept 5) convergence between China and the West in their English language propaganda discourses, whilst simultaneous divergence in their presuppositions: ‘usthem’ by the West and ‘we are the same’ by China. To conclude, this paper will contribute to the study of propaganda and its discourse by analysing how propaganda is understood and utilised in both worlds, and hence to uncover the discourse power struggle between the two, which contributes to the propaganda discourse itself. Hence, to untie the misconception of propaganda.

Keywords: China, discourse, power, propaganda

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