bluuebunny/crossref_metadata_2025 huggingface dataset:
Offset Cancellation and Programmable Gain Design for Switched Capacitor Amplifier in Digital DC-DC Converter
Authors: Zhang Panpan , Zhao Peng , Chen Xiaoping , Song Yang , Zhang Zongjiang
Published: April 2021

This paper presents a fully differential switched capacitor amplifier with programmable gain design and offset cancellation technique used in digital DC-DC converter. To trade off the effective resolution for dynamic range of the error ADC, the gain of the switched capacitor amplifier is designed programmable that can be configured 1X, 2X, 4X or 8X. To improve system offset performance, the first stage is utilized full-differential switch-capacitor architecture conducive to common mode noise rejection and differential offset cancellation caused by charge injection. In addition, to cancel the offset brought by amplifier input stage, offset cancellation techniques are also implemented. The offset voltage is stored in calibration capacitor in sampling phase and cancels the input offset in amplification phase. This proposed circuit is simulated in 180nm 4P6M CMOS technology. From the simulation result, the offset voltage is fully cancelled. In addition, programmable gain design is also verified that dynamic adjustment accuracy in DC-DC feedback loop in X8 is superior than X1.
A Diagnosis Method of Vibration Fault of Steam Turbine Based on Information Entropy and Grey Correlation Analysis
Authors: Chen Fei , Cao Hao , Zhang Bolin , Jilong Wei
Published: April 2021

Based on the faulty signals collected from the rotor test platform, the grey correlation analysis was studied for vibration fault diagnosis of steam turbine shafting. The reference faulty matrix and the calculation model of grey correlation degree were established based on three kinds of information entropy. The analysis shows that grey correlation analysis is a useful method for fault diagnosis of shafting and can be used as a quantitative index for fault diagnosis.
Research on Measurement Traceability Method of Dynamic Shear Rheometer
Authors: Miao Na , Peng Lu , Chen Lei , You Chunmei , Wang Yixu
Published: April 2021

The dynamic shear rheometer is the basic instrument for studying viscoelastic materials. In this paper, the influences of the accuracy of dynamic shear rheometer were analyzed, calibration parameters were proposed and verified through experiments, and the extended uncertainty was 3.0 (k=2), which verified the feasibility of using viscosity reference materials as a technology to realize the measurement traceability of dynamic shear rheometer, and the traceability method can be promoted and applied to the traceability of various equipment.
Optimization Design of Solar Power Generation System Based on Big Data
Authors: Liang Yuwen , Yang Meiyi
Published: April 2021

Based on the data analysis and collection of optical thermal power station, this paper uses big data and machine learning method to mine the knowledge and rules contained in various data to guide the operation. Combined with various data sources, the model is established, and the system optimization and operation reference research are carried out.
Winding Vibration Analysis of UHV Shunt Reactor With Finite Element Method
Authors: Wu Xiaowen , Cao Hao , Tan Ben
Published: April 2021

In order to investigate the winding vibration characteristics of UHV shunt reactors, a scale model of UHV reactor is designed and manufactured with rated voltage 29.27 kV and rated current 669.9 A. The magnetic-structure coupled finite element model is proposed to analyze the winding vibration of the reactor. With this model, the distribution and time variation magnetic flux density (MFD) of the reactor is calculated. The Lorentz force in the winding is used as load input for structure analysis. The vibration displacement and acceleration distribution and variation process of the reactor winding is obtained.
An Experimental Study on High-Pressure Hydrogen Compatibility of Rubber Seals at FCV Refuelling Receptacles
Authors: Hao Dong , Yang Yunpeng , Gao Bin , Zhang Shimin , Zhang Yanyi , Wang Renguang
Published: April 2021

A method is proposed to test the sensitivity of high-pressure hydrogen compatibility of rubber O-ring seals at FCV refuelling receptacles based on a long-term high-pressure pure hydrogen full-immersion environment testing, in combination with such Chinese standards as the determination of the effect of liquids of rubber and FCV refuelling receptables. Through an aging property test system, the high-pressure pure hydrogen full-immersion testing is conducted for 5 groups of rubber O-ring seals to be measured. Before and after the testing, an electronic balance is used to measure the mass of the rubber O-ring seals, obtaining changes in mass and volume. At last, on the basis of the changes, the sensitivity of the seals of various models and in diverse experimental groups to the high-pressure hydrogen compatibility is obtained through our analysis.
Big Data: What are the Implications for Public Sector Policy in Society 5.0 Era?
Authors: Rahmanto Fajar , Pribadi Ulung , Priyanto Agus
Published: April 2021

Modernization in various sectors of life has made data and information valuable, which has an impact in changing people’s lives. One of the changes is how people get information from a large amount of data to be used in the public development sector. Public policy, as a solution to solve various public problems, needs to be supported by accurate data and information facts. With a massive amount of data, this has an impact on public sector organizations to be able to store and analyze various types of information for public policies consideration. The term ‘Society 5.0’ has emerged, a concept that refers to revolution in people’s lives through the use of technology by considering the humanities aspect. The potential for the huge benefits of big data technology is interesting to know as to whether big data can be used for the public policy formulation process. Therefore, this article will provide an overview of the implications of big data for the public policy process in society. This research uses qualitative method with literature study approach. The data came from websites and government documents related to the use of big data in public policies, analyzed using the NVivo12 Plus application. The emergence of big data, as a basis for making public policy, can be utilized for analysis, which includes social data analysis, historical data analysis, and predictive data analysis which can influence accuracy in the policy decision making. Public policy in the era of society 5.0 is vital to be realized through the use of big data as a source of information supported by technology and the readiness of actors in the policy-making process.
Implementation of Performance Management in Artificial Intelligence System to Improve Indonesian Human Resources Competencies
Authors: Gaol Porman Lumban
Published: April 2021

This study aims to analyze and explore the artificial intelligence system with Performance Management Studies through the POAC (Planning, Organizing, Actuating, and Controlling) method to improve the competence of human resources in Indonesia. The era of digital transformation is part of the process of greater technology, and this is a change related to the application of digital technology in aspects of life that exist in society. Indonesia is in need of higher quality resources to deal with artificial intelligence systems that demand smart company operations, smart services and innovative products. Performance management analysis is needed in the artificial intelligence system that can be applied in the development of science and human resource competencies in Indonesia, which include: analyzing HR competencies in the working world and industry systems, synergizing the role of higher education with relevant ministries and agencies, analyzing and mapping the education budget, and analyzing the HR needs of industry or companies with an artificial intelligence system. It is expected that the POAC method can be used as a reference for developing human resources competencies in the application of artificial intelligence systems in Indonesia.
Artificial Data Management in Reaching Conditional Cash Transfer of Program Keluarga Harapan (PKH) Utilizing Simple Addictive Weighting
Authors: Kasiwi Aulia Nur , Nurmandi Achmad , Mutiarin Dyah , Azka Muhammad Fatih
Published: April 2021

The main challenge in implementing a poverty reduction program is to identify precisely the targets that will benefit a program. Program Keluarga Harapan (PKH) is a social protection program from the central government through the provision of conditional cash transfers to Low-Income Households (RTSM)/Low-Income Families (CBOs), which are designated as Program Keluarga Harapan beneficiary families. Program Keluarga Harapan is the conditional cash transfer (CCT) program to reduce poverty by making welfare programs dependent upon the receivers’ actions. The accuracy of choosing targets directly impacts the achievement of social protection programs’ objectives in poverty alleviation. This research would like to dig up how Jogjakarta’s government is accurate to reach the beneficial Program Keluarga Harapan recipient. In terms of Jogjakarta’s government using the support system to classify the low-income family as the receiver of conditional cash transfers. Therefore, this research will explain which decision-making model used by the government of Jogjakarta managed by a computerized system, known that computerized data processing is expected to present information rapidly, precise, clear, and directed as the exact target for the program.
Internet of Things for Smart City. A Case Study: SMEs Project in Sleman Regency
Authors: Fridayani Helen Dian , Atmojo Muhammad Eko
Published: April 2021

IoT improves the proficiency, precision, and viability in activities and the board of such development ecosystem targeting and ensuring a high caliber of life and animating advancement procedure of organizations. A smart city has been created by setting up cutting edge business-drove development in joint with government and companies to give a solid start business condition, sensible charges, and minimal effort to live and to work together. This paper summarizes the role of IoTs for Small Medium Enterprises in Sleman Regency, divided into 2 categories: development and marketing. This particular study contributes to the strategy of IoTs development for Small Medium Enterprises’ project.
Implementation of E-Tourism In Aceh Province for Future Sustainable Development through Media Promotion
Authors: Ulfa Khalida , Pribadi Ulung , Herizal  , Suswanta
Published: April 2021

E-tourism is a new strategy in Indonesia for the tourism development. Indonesia possesses great potential in tourism, including marine, culture, history, culinary and many other types of tourism. The concept of sustainable development remains the best development principle, one of which is as a guide in the development of tourism and is used for economic growth in the society. This research is based on a previous article published in Sustainability by presenting an integrated framework using a comprehensive and in-depth review on literatures related to tourism. Application of E-Tourism in Aceh province’s tourism management through media promotion is to boost economic growth in tourism development and management. Tourism in Aceh Province has very good potential. This condition has the potential to market tourism using social media. In this modern era, humans tend to use social media as a means of finding information. In this case, the role of social media, such as website and Twitter, is a suitable tool for marketing E-Tourism in Aceh Province. This study used descriptive qualitative method. Data sources were be obtained from Acehtourism, travel websit report documents, and journals related to the research topic. The data were analyzed using the Nvivo 12 plus application and crosstab. The results showed that the implementation of E-tourism in Aceh Province through social media was very influential. This social media is a promotion platform for the region because it is easier, more effective, strategic, and this can increase the regional economic development and the sustainable community in the future.
Artificial Intelligence and Decision Support System to Determine Policies for Controlling River Pollution from Industrial Sectors
Authors: Sulistyaningsih Tri , Sunarto  , Saiman  , Suhariyanti  , Oktaviari Vinggi
Published: April 2021

One of the principal difficulties faced in developing countries is poor water quality. Approximately 90% households and industrial wastes are discharged untreated properly, directly into the ground and surface water. This research aims to analyze the use of artificial intelligence as a decision support system (DSS) to monitor and determine policies for controlling river pollution from industrial sectors. This study uses an interpretive approach or a qualitative approach by implementing the library research method. Integrated river basin management involves all management issues associated with the supply, use, rehabilitation, protection, pollution, and many others in a river basin. In the decision-making process, it considers the relations between the abiotic and the biotic part of the various water systems, between the ecological and economic factors, and between the various stakeholder interests. The use of technology by policymakers is important to address these water quality-related challenges. Therefore, DSS as an artificial intelligence tool is required to carry out river basin management processes. Thus, water managers can make policies and decisions on the implementation of measures to improve the quality of surface water in the river faster and more precise.
The Influence of Artificial Intelligence to Support Halal Tourism Policy in South Korea
Authors: Marlinda A P , Cipto B , Al-Fadhat F , Jubba H
Published: April 2021

This study focuses on the influence of Artificial Intelligence in the form of application (software) supporting South Korea’s halal tourism policy. Specifically, this study analyses the types of correlations between the software and the implementation of halal tourism policies in South Korea. This illustrates the influence of applications on users as Muslim tourists in South Korea. Thirty applications were randomly selected, and data were collected from Google Play Store devices through Android for the period between 2010-2020. In this study a qualitative approach was applied, and literature study was chosen to examine the data. Indicators available on the Google Play Store was used, complemented by the criteria of halal tourism collected by the authors from various sources. Based on these indicators, the results of the analysis revealed that more than 50 percent of the mentioned applications were helpful for users (Muslim tourists) led to a conclusion that artificial intelligence supports the implementation of halal tourism policies in South Korea.
Transformational Leadership in Creating Good District Government
Authors: Dema Herman , Rusdi Andi Fadel , Yasin Akhmad , Hamid Hariyanti , Abriyanti Nur
Published: April 2021

This study aims to determine the role and impact of transformational leadership in creating good governance in sub-district government. The method used is descriptive quantitative, with a sample of 31 respondents. Data collection techniques used in this study were observation, questionnaires, literature studies, and interviews. The collected data is processed using a frequency table. The results showed that the role of transformational leadership in creating good governance in sub-district government is categorized as useful. The most certain thing is if the leader can provide training for officials (facilitation). The impact of transformational leadership in creating good governance is that apparatus compliance increases both to leadership in the sub-district government. The impact is seen from the collaboration of the authorities when serving as well as the moral leaders of the apparatus when serving the community. Therefore, this study suggests that leaders often provide training and act as facilitators in an activity.
Observed Data of Forest Fire Hotspots effects on Respiratory Disorder by Arc-GIS in Riau Province, Indonesia
Authors: Purnomo Eko Priyo , Rahmasari Farindira Vesti , Trisnawati Dina Wahyu , Agustiyara  , Erviana Rima
Published: April 2021

The paper shows that air quality aspects rise from forest fires in Indonesia and they have associations with a wide range of adverse health outcomes, including respiratory health problems. Due to the unpredictable nature of forest fires, it is challenging for public health authorities to evaluate the potential exposures before they occur reliably. Using GIS software, zoning was made om Riau Province, Indonesia. The data shows that the highest fire hotspot was in 2015 by 12,854 and the lowest was 527 in 2017 as well as the lowest Respiratory Disorder Cases in 2017 was 371,044. The Finding proves that smoke has a significant negative effect on increasing respiratory problems Therefore, it also indicates that smoke and haze forecastings are effective tools and challenging to be developed that can be used as public health predictions and establish a suitable policy on forest fires. However, their inherent uncertainties limit their widespread adoption. Observed measurements from air quality monitoring networks and remote sensing platforms are more reliable, but they are inherently retrospective.
Digitalization Era: Website Based E-Government
Authors: Ahmad Jamaluddin , Hardianti  , Nilwana Andi , Muliani  , Hamid Hariyanti
Published: April 2021

The problem in this research is that public services are still manual because the websites in each agency are still inadequate to provide online services, the condition of the website cannot be accessed, many pages are blank and the news displayed is not up to date, this indicates that the website of the agency from The Regional Work Units in Enrekang Regency has not met the standards set by Diskominfo in 2017. The purpose of this study is to see the quality of the website in terms of transparency, effectiveness, and efficiency. Moreover, to see the role of social media in the application of website-based e-government in the Enrekang District Work Unit (SKPD). Research using quantitative methods. The data in the study used online media from the Enrekang Regency website by looking at specific criteria from the agency website of the Regional Work Unit. The technique for calculating existing data is that if there is data available, it will be given a score of 1 and if the information is not available on the website it will be given a score of 0. The results of this study, the websites of local government agencies, are not transparent, ineffective, and inefficient. The role of social media is also not influential because there is no feedback provided by the government on input and questions given by the public.
Usability assessment of virtual reality as a training tool for oral presentation
Authors: Daniels M M
Published: April 2021

One of the widely used teaching-learning strategies in the educational sector is the delivery of oral presentation by students. They are tasked to present their outputs-such as research paper, project, case study findings—to a group of audience. The problem experienced by most students in this type of task is the fear of public speaking combined with the pressure of relaying information effectively. In practice, this problem is resolved by giving more opportunity to students to rehearse repeatedly in front of peers. Organizing such setup, however, becomes almost impossible during times of pandemic when face-to-face interaction is limited, if not prohibited. Hence, this study ventured on assessing the usability of an alternative solution. This is with the use of virtual reality technology that can simulate the traditional training scenario and render it in a virtual environment. Three categories of participants were involved in the rating of its usability - IT students, non-IT students and Trainers. They were given ample time to navigate a public speaking app using a VR headset. Afterwards, they accomplished a survey questionnaire where they assessed the usability of the VR tool as a mode of training for oral presentation. Findings show that the usability rating of virtual reality as a training tool for oral presentation can vary depending on the technological background of users. This is due to the lack of on-screen assistant that would guide users in navigating the system. Despite these minor problems, the use of virtual reality as a training tool for oral presentation is highly recommended. This is supported by the unanimous positive response of participants in the SUS scale measuring their interest in using the VR tool for oral presentation.
Exploring Nano Biotechnology for detecting specific disease in Medical diagnosis and Therapeutic
Authors: Thangamani M. , Kavitha Bharathi S. , Suresh Kumar N.
Published: April 2021

Nanobiotechnology connects the scientific openings between chemistry, physics and biology on the nanoscale. These guides to a lot of modern techniques help and create good result in medical-phtherapeutic appliances. Now a day nanoparticles good aspirants for drug discovery and new therapeutic applications. It consists of the nanotechnology and biotechnology. Nanobiotechnology will help the combination of therapeutics with diagnostics and make easy to improve the specific medicine suitability for an individual and prevent the immune system from side effect drugs delivery. This article explores the nano biotechnology y for detecting specific disease in medical field.
Seismic performance evaluation of steel building frames with modified dual-pipe damper
Authors: Bincy V , Usha S
Published: April 2021

Building performance against resistance to earthquake depends on selection of right building material with right properties. Steel frame structures are widely accepted due to its flexibility and seismic resistance property. However the practice of seismic retrofitting techniques in steel structures helps in the betterment of seismic performance of the building. A number of researches on simple and cost effective Metallic Yielding Device (MYD) are being conducted to evolve the best equipment. Dual-Pipe Damper (DPD) is one of the MYDs, which works on the principle of passive energy dissipation. A recent study brings the effective dimensions of pipes in DPD which can be implemented in a steel building frame conforming to IS 800:2007. This paper aims to study the effect of number of pipes in DPD by conducting parametric study using push over analysis. Three different configurations of optimized DPD installation in the multi-storey building frame are also studied. The Modal and Time-History analyses are performed on multi-storey frame with optimized DPD fixed at three configurations of steel frame conforming to IS 800:2007 to optimize the configuration.
Corrosion control of reinforced concrete structures in construction industry: A review
Authors: Arya E K , Dhanya B S
Published: April 2021

Corrosion of steel reinforcement is one of the main deterioration phenomena which affect the durability of reinforced concrete structures. Together with the structural damages, corrosion will also increase the cost associated with it. Therefore, protection of reinforcing steel in concrete structures from corrosion is an inevitable need. Various protection techniques are in practice to mitigate corrosion of reinforcing steel in the concrete structure such as use of patch repairing, protective coating, impressed current method, and sacrificial anodes. Among these, electrochemical protection technique using sacrificial anodes can be suggested as a very effective tool for corrosion mitigation. Sacrificial anode cathodic protection system is a less popular corrosion control technique because of lack of awareness about the benefits of this method and the wide usage of other corrosion control practices. This paper provides a critical review on the common techniques in construction sites used for corrosion control of reinforced concrete structures. An overview of the benefits of sacrificial anode cathodic protection system, its working and installation is also provided in this paper.
A study on economic feasibility of fly ash and ground granulated blast furnace slag based geopolymer concrete
Authors: Chithra K S , Binoy T , Harismitha A , Ananth R K , Deepa M
Published: April 2021

The rapid increase in the greenhouse gas emission has affected the ecological balance adversely which tends to the need of sustainable development in nature. The carbon dioxide produced during cement production is about 7% globally and it is the second most consumed product in the world. To mitigate this crisis, Geopolymer concrete (GPC) which constitutes industrial wastes like Ground Granulated Blast Furnace Slag (GGBS), flyash, rice husk is considered as a more eco-friendly and economically feasible alternative to Ordinary Portland Cement (OPC) based concrete. The reduction in the carbon dioxide emission from cement production can contribute significantly to the turning down of the global thermostat. The feasibility of production of GPC is much more safe, secure and reliable as it has more strength than conventional concrete [1]. The objective of the study is to compare the economic feasibility of conventional concrete and GPC. In this study, the rate analysis is done for optimum combination of flyash and GGBS based GPC and conventional concrete. From earlier studies flyash and GGBS based GPC is prepared by activating mixture of sodium silicate and NaOH solution. Optimum strength ratio obtained for flyash and GGBS is 1:1. In this study the analysis is done for GPC M 25 grade, conventional concrete of M 25 grade and is observed that GPC is more economical than conventional mix.
Computation of stress concentration factor of tubular joints for the fatigue analysis of steel structures
Authors: Althaf M , Muhammed Navvar K , Prakash Gowtham , Varghese Noel , Navaneeth C A
Published: April 2021

The offshore structures are welded tubular structures which are continuously subjected to cyclic environmental loads like waves, winds, currents, earthquakes etc. These cyclic environmental loads (predominantly wave loads) will induce time varying cyclic stresses on the offshore structures causing fatigue damages even at very low nominal stress levels. Fatigue failure is defined as the tendency of a material to fracture by means of progressive brittle cracking under repeated alternating or cyclic stresses of intensity considerably below the normal strength. Fatigue is very critical at the welded joints, because the stresses at the welded regions are several times higher than the nominal stress. Stress Concentration Factors (SCFs) converts the nominal stress into higher stresses known as hot spot stresses. These SCFs are very sensitive in the computation of fatigue life of steel structures. A small difference in SCFs can cause a huge difference in fatigue life of steel structures. Different empirical methods give different values of SCFs for the same element, hence different fatigue life. This study aims to investigate the stress concentration factor of different configurations of tubular joints numerically using Finite Element Analysis (ANSYS) under certain boundary conditions and compare the result with the SCF obtained from empirical method (using parametric equations).
Potential application of cement amended marine clay as liner material
Authors: Veena V , Reghunath S , Cyrus S , Abraham B M
Published: April 2021

One of the major problems being faced today in the society is solid waste disposal. Compacted clay soils are commonly used as liner materials in waste containment systems. As marine clay is abundant in the coastal belt of Kochi, this locally available soil was used in the study. Desiccation cracking of clay mass can lead to development of shrinkage cracks and also provide pathways for moisture migration into the landfill. In order to minimize the adverse effect of cracks, the behaviour of sun-dried marine clay amended with cement in different percentages of 1%, 2%, and 4% were studied. To stimulate the field conditions, the samples were subjected to alternate wetting and drying cycles. For different cement content, three cycles of alternate wetting and drying were performed. The study indicates that the extent of crack formation decreases with increase in cement content and the optimum percentage of cement amendment is 4%.
A study on seismic response of buildings on coir mat reinforced sand bed
Authors: Sreya M V , Jayalekshmi B R , Venkataramana Katta
Published: April 2021

The present study examines the efficacy of coir mat as a seismic isolation material for reducing the earthquake energy transferred and, so to reduce the dynamic response of the building. A three-dimensional finite element simulation of field-scale models of G+2 and G+3 buildings resting on raft foundation in a sand bed, with and without the seismic isolation mechanism has been carried out by time history analysis with El Centro (1940) input motion. Seismic responses such as roof acceleration, roof deflection, bending moment and shear force of G+2 and G+3 buildings are studied. Variation in the base shear ratio which is defined as the ratio of seismic base shear to the total weight of the building is also analyzed by incorporating the three-dimensional soil-structure interaction effect. The results from the analysis inferred that the reinforcement of the coir mat as a seismic isolation medium limits the transmission of earthquake energy to the superstructure.
Simulation of flow pattern around series of groynes with different orientations in meandering channels
Authors: Indulekha K P , Jayasree P K , Sachin S
Published: April 2021

The mechanism of flow and turbulence around groynes in a meandering channel is very complex phenomena. To simulate the flow pattern around groynes in meanders a 3D numerical model was built with groynes of different inclinations by using ANSYS Fluent. The developed model was verified by the results of experimental study in meanders. Pressure, velocity, stream lines and turbulent kinetic energy for different groyne angles such as 15°, 30°, 45°, 90°, 120° and 150° were compared and analyzed to find the ideal angle configuration for different functions. Streamlines profiles were studied to understand more about the formation of scours and vortices around the groyne. The study of streamline profiles helped in the study of vortex and scours. The most dynamic variation in pressure and turbulent kinetic energy within the contours were found for groynes with 90° orientation. Large numbers of vortices between the groynes were observed for groynes with 15° and 90° orientation and these vortices were observed between the second and third groynes. For groynes in the meandering, the ideal angle for controlling the velocity was found out to be 45°, as it showed very small number of vortices in the groyne field. The results of the study showed that numerical modelling could be used efficiently for the study of flow and turbulence around groynes in meanders.
Impact of urbanization on flooding in chalakudy river
Authors: Parvathy Sethu , Thomas Reeba
Published: April 2021

Extreme events like floods are a concern for any country in terms of the damages caused to life as well as property. The recent trend of unpredictable rainfall in India leads to significant changes in the flow of the river and basin characteristics, which contribute to the aggravation of floods. In the cataclysmic flood in the year 2018 in Kerala, the Chalakudy river basin was completely inundated. This region has undergone extensive environmental changes since the 1990s due to agricultural expansion, deforestation, increased urbanization etc. These indicate the need for conducting a hydrologic and land use/land cover (LULC) change analysis to identify the causes, effects and solutions to mitigate the devastating effect of floods. This goal is achieved with the help of Geographic Information System (ArcGIS) and a hydrological model (HEC-HMS). The results from the study shows that tremendous change in land use pattern has occurred over the past few decades and the notable among them is the 1003.9% increase in built-up area. The increase in flood peak of the devastating Kerala Flood 2018, exclusively due to this land use change/urbanization is found to be about 22% in this study area.
Combined coagulation and intermittent sand filtration for on-site treatment of greywater
Authors: Singh S , Ahammed M M , Shaikh I N
Published: April 2021

Performance of coagulation followed by intermittent saturated sand filtration system was evaluated for greywater treatment using real greywater. Filters with two different grain sizes were used to study the effect of media size on the removal. Filters were charged daily with 20 L of greywater coagulated with polyaluminium chloride (PACl). Performance of the filters were evaluated based on physicochemical and microbial parameters. Results showed that coagulation followed by sand filtration resulted in 94, 76 and 80% reduction in turbidity, BOD and COD respectively. Also, more than 99% of total and faecal coliform removal was observed. Sand filter with smaller grain size performed significantly better than the sand filter with coarser grain size. Coagulation followed by filtration showed stable and reliable performance as the effluent quality was insensitive to fluctuations in influent quality. Combined coagulation and sand filtration produced effluent conforming to different reuse standards.
Thermal behaviour of heated stationary inner cylinder of a concentric vertical annulus formed with rotating outer cylinder
Authors: Chithrakumar V K , Venugopal G , Rajkumar M R
Published: April 2021

Experimental studies have been conducted to investigate the convective heat transfer from the inner stationary heated cylinder of a vertical concentric annulus with outer cylinder rotating, corresponding to rotation speeds from 500rpm to 1000rpm. The centrifugal force arising due to the outer cylinder rotation and the buoyant force developed due to the heat generated from the stationary inner cylinder has been characterized by using a non-dimensional number denoted as Rotation parameter (ζ = Reω

2/Gr). The influence of Rotation parameter on the convective thermal behaviour of the heated stationary inner cylinder has been explained.
Design and control of a two-wheel self-balancing robot
Authors: Mathew Alex , Ananthu R , Binsy P , Vahid Abdul , Thomas Ciby , Sidharthan S
Published: April 2021

Designing the self-balancing two wheeled mobile robots and stabilizing it has gained a lot of momentum in research areas. Instead of complex control system that are mostly scene in these research papers this paper introduces a new design of two wheeled robot structure which fulfils the required level of stabilization without any complex control system. To achieve this, the structure is designed with a vertical straight line motion. After deriving the mathematical model, the model is simulated in Matlab Simulink. The simulation is carried for step, ramp and uneven terrain input conditions.
Evaluation of microstructural and mechanical characteristics of stir cast A356/(0 to 20) wt.% SiCp composites
Authors: Jibin Bose T C , Hashim M , Rajeev V R
Published: April 2021

In this work A356/(0-20%) wt.% SiCp composites were prepared from A356 base alloy through the most economical casting route i.e., stir casting method. Silicon carbide of particle size 23 micron was used as reinforcement to prepare A356/10wt.%SiCp and A356/20 wt.% SiCp composites. Microstructure of A356 and A356/(0-20)wt.% SiCp composites were examined using Leica optical microscope. Microstructural Examination showed that A356/(0-20)wt.% SiCp composites have uniform distribution of SiC particles within the two composites apart from α aluminium and eutectic Si compared to its base alloy. Hardness and tensile test were conducted for heat treated and as cast specimens. It was found that heat treated A 356 alloy and its composites have better hardness than as cast. Tensile tests were conducted on both alloy and its composites and found that brittle fracture was more likely to occur in composites wherein ductile fracture pre dominates in base alloy. XRD analysis of both alloy and its composites showed the major hardening phases such as Al2Cu, Mg2Si etc.
A study on electrochemical oxidationof phenol for wastewater remediation
Authors: Divya N , Sreerag A V , Yadukrishna  , Joseph Tiwin , Soloman P A
Published: April 2021

This era having been driven by the industrial revolution caused a major outbreak of pollutant quantity in water. Phenol is one of the most toxic chemicals and electrochemical oxidation is undoubtedly one of the attractive alternatives for the degradation of phenol available in wastewater. The present study aims at finding the best combination of operating parameters maximizing the phenol removal by electrochemical treatment of phenolic wastewater. Synthetically prepared phenol solution of various concentrations was electrochemically oxidized using a cylindrical flow cell. It was found that initial phenol concentration, time, current density, and salt concentration have a strong influence on the removal of phenol. Furthermore, based on the results obtained, a second-order regression model was proposed to predict the responses. Analysis of variance (ANOVA) result and the R2value of the model shows that the model could very well predict the realistic situation. According to the prediction by the model, the best set of operating conditions giving the complete removal of phenol is Time: 9.27 min, Current density: 3.58 A/dm2, supporting Electrolyte concentration: 3.29 g/L, and Initial Concentration: 13.64 ppm.
An assessment on the effect of titanium dioxide & iron oxide nano-particles in industrial waste water decontamination
Authors: Narayanan Jishnu , Manjith Kumar B , Jishnu M
Published: April 2021

The aim of this paper is to identify a technique to detoxify the industrial waste water using metal oxide nanoparticles. Waste water from manufacturing or chemical processes in industries contributes to water pollution. Industrial waste water usually contains specific and readily identifiable chemical compounds. It destroys aquatic life and reduces its reproductive ability. Eventually it is hazardous to human life. Most major industries have treatment facilities for industrial effluents but this is not the case with small-scale industries, which cannot afford enormous investments in pollution control equipment. In this paper, an experimental study was conducted to study the effect of titanium dioxide and ferric oxide nanoparticles in detoxification of industrial waste water. Here the adsorption property of these nanoparticles was used for the detoxification of industrial waste water. The nanomaterials were synthesized using high energy ball milling machine and the characterization was done through scanning electron microscopy. After the preparation, these Nano sized titanium dioxide and ferric oxide powder were introduced to the pretested waste water. Due to the adsorption property of these nanomaterials, it is observed that the contaminants like sulphate, cadmium, lead and chlorides are adsorbed to some extent.
A review on polymer based adsorbents for CO2 capture
Authors: Indira V , Abhitha K
Published: April 2021

Carbon dioxide (CO2) is the essential ozone harming gas and its emissions ends up in worldwide temperature alteration that leads to climate change. CO2 adsorption on solid materials such as zeolites, carbonaceous materials, metal organic frameworks and silicaisone of the efficient method for carbon dioxide removal. This review focuses on polymer-based adsorbents for CO2 capture. Porous organic polymers like hyper-cross linked polymers (HCPs), covalent organic frameworks (COFs), conjugated microporous polymers (CMPs) and covalent triazine-based frameworks (CTFs) display CO2 catching limit of around 3 to 6 mmol/g at 273K and 1 bar. Polymer such as polyethyleneimine when incorporated with adsorbents offers improved CO2 adsorption at higher temperature. CO2 adsorbents developed from polymer waste can play a dual function in environmental pollution control. In industrial packed columns, polymer composites are considered as superior choice for CO2 capture.
Synthesis of starch-graphene oxide composite membrane for heavy metal removal
Authors: Sajeena Beevi B , Blessmy Rose K , Aleena Shelvi K , Anand Kumar M , Mathew Reethu
Published: April 2021

The development of a cost-effective biopolymer composite membrane using starch is found to be efficient to be used for heavy metal removal from waste water. In the present work we have used starch containing amylose/amylopectin as the biopolymer and graphene oxide (GO) as the carbon nanomaterial to develop the composite membrane. Synthesis of graphene oxide, characterization of the graphene oxide, composite preparation using starch-graphene oxide, development of the membrane, characterization and analysis of the heavy metal removal efficiency were the major objectives of the present work. Scanning electron microscopy (SEM), Atomic absorption spectroscopy (AAS) and Raman spectroscopy were used for the characterization studies. Analysis being done for studying the effectiveness of membrane for removal of heavy metal ions including Pb, Cd, Zn and Mg by varying certain parameters, revealed that the membrane is efficient in the range 85-95 % for lower concentrations of these metals in the waste water.
Tribological investigation of peek composite reinforced with nanometre sized potassium titanate powder
Authors: Samraj K
Published: April 2021

Tribological behaviour of poly ether ether ketone (PEEK) reinforced with (0-15 wt%) nanometre sized potassium titanate powder has been investigated on the pin on disk configuration. It has been found that the tribological properties of PEEK composite get enhanced with the increase in concentration of potassium titanate content. Tribological studies of the PEEK polymer-matrix composite shows that it forms a thin transfer film which impact the wear behaviour by reducing the coefficient of friction and wear rate. The worn surface is characterized using optical microscope and scanning electron microscope for analyzing the surface morphology. X-ray diffraction pattern and Fourier-transform infrared spectroscopy of the potassium titanate were also observed. The hardness value of the PEEK composite was obtained by durometer hardness test which found to be improved with concentration of potassium titanate. Moreover, the composite resulted in reduced wear rate and coefficient of friction with the addition of potassium titanate to the PEEK.
A novel 4D cell culture mimicking stomach peristalsis altered gastric cancer spheroids growth and malignance
Authors: Zhao Juzhi , Wang Ruiqi , Zhang Jinyu , Zhao Yufang , Qiao Shupei , Crouzier Thomas , Yan Hongji , Tian Weiming
Published: April 2021

In vitro cancer models that can largely mimic the in vivo microenvironment are crucial for conducting more accurate research. Models of three-dimensional (3D) culture that can mimic some aspects of cancer microenvironment or cancer biopsies that can adequately represent tumor heterogeneity are intensely used currently. Those models still lack the dynamic stress stimuli in gastric carcinoma exposed to stomach peristalsis in vivo. This study leveraged a lab-developed four-dimensional (4D) culture model by a magnetic responsive alginate-based hydrogel to rotating magnets that can mimic stress stimuli in gastric cancer (GC). We used the 4D model to culture human GC cell line AGS and SGC7901, cells at the primary and metastasis stage. We revealed the 4D model altered the cancer cell growth kinetics mechanistically by altering PCNA and p53 expression compared to the 3D culture that lacks stress stimuli. We found the 4D model altered the cancer spheroids stemness as evidenced by enhanced cancer stem cells (CD44) marker expression in AGS spheroids but the expression was dampened in SGC7901 cells. We examined the multi-drug resistance (MDR1) marker expression and found the 4D model dampened the MDR1 expression in SGC7901 cell spheroids, but not in spheroids of AGS cells. Such a model provides the stomach peristalsis mimic and is promising for conducting basic or translational GC-associated research, drug screening, and culturing patient gastric biopsies to tailor the therapeutic strategies in precision medicine.
Enhanced dispersive properties of graphene plasmons on substrates of composite materials
Authors: Zhou Yun-Cheng , Ud Din Rafi , Ahmad Iftikhar , Ge Guo-Qin
Published: April 2021

Graphene plasmons (GPs) have opened new perspectives for nanophotonic applications due to their intense fields and low losses at certain frequencies. In this work, we investigate transverse magnetic or p-polarized plasmonic modes supported by a doped graphene sheet cladded between a dielectric and a nanocomposite material in tera Hertz regimes. We show that if there is a certain mechanism to excite and couple localized surface plasmons (LSPs) on the surfaces of the metal-nanoparticles to GPs, this coupling leads to higher wave vectors for the GPs, which gives significant wave localization and intense fields near the surface. Along with dispersion relation, we discuss different properties of GPs supported by the waveguide geometry and its interaction with LSPs. Moreover, we compare the results with GPs supported by dielectric/graphene/dielectric geometry and discuss their tunability with different controlling parameters. We adopt realistic parameters to describe the geometry, therefore the study can be realized experimentally.
Trap induced long exciton intervalley scattering and population lifetime in monolayer WSe2
Authors: Wagner Julian , Kuhn Henning , Bernhardt Robin , Zhu Jingyi , van Loosdrecht Paul H M
Published: April 2021

Monolayer transition metal dichalcogenides (TMDCs) hold the best promise for next generation optoelectronic and valleytronic devices. However, their actual performance is usually largely affected by the presence of inevitable defects. Therefore, a detailed understanding of the influence of defects on the dynamic properties is crucial for optimizing near future implementations. Here, the exciton population and valley scattering dynamics in a chemical vapor deposition grown large size monolayer WSe2 with naturally abundant vacancy and boundary defects were systematically investigated using polarization controlled heterodyned transient grating spectroscopy at different excitation wavelengths and temperatures. Slow and multi-exponential decay dynamics of the exciton population were observed while no sign of any micron scale diffusive transport was identified, consistent with the effect of exciton trapping by defects. In general, two different kinds of exciton species were identified: one with short population lifetime (∼10 ps) and extremely fast intervalley scattering dynamics (<200 fs) and in contrast another one with a long population lifetime (>1 ns) and very slow intervalley scattering dynamics exceeding 100 ps. We assign the former to non-trapped excitons in the nanometer scale and the latter to defect-bound excitons. Temperature dependent intervalley scattering dynamics of the trapped excitons can be understood in terms of a two optical phonon dominated process at the K point in momentum space. Our findings highlight the importance of the intrinsic defects in monolayer TMDCs for manipulating exciton valley polarization and population lifetimes, which is key for future device applications.