Search results for: supersonic cross flow
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8409

Search results for: supersonic cross flow

4569 Preliminary Study of Desiccant Cooling System under Algerian Climates

Authors: N. Hatraf, N. Moummi

Abstract:

The interest in air conditioning using renewable energies is increasing. The thermal energy produced from the solar energy can be converted to useful cooling and heating through the thermochemical or thermophysical processes by using thermally activated energy conversion systems. The ambient air contains so much water that very high dehumidification rates are required. For a continuous dehumidification of the process air, the water adsorbed on the desiccant material has to be removed, which is done by allowing hot air to flow through the desiccant material (regeneration). A solid desiccant cooling system transfers moisture from the inlet air to the silica gel by using two processes: Absorption process and the regeneration process. The main aim of this paper is to study how the dehumidification rate, the generation temperature and many other factors influence the efficiency of a solid desiccant system by using TRNSYS software. The results show that the desiccant system could be used to decrease the humidity rate of the entering air.

Keywords: dehumidification, efficiency, humidity, Trnsys

Procedia PDF Downloads 434
4568 Plagiarism Detection for Flowchart and Figures in Texts

Authors: Ahmadu Maidorawa, Idrissa Djibo, Muhammad Tella

Abstract:

This paper presents a method for detecting flow chart and figure plagiarism based on shape of image processing and multimedia retrieval. The method managed to retrieve flowcharts with ranked similarity according to different matching sets. Plagiarism detection is well known phenomenon in the academic arena. Copying other people is considered as serious offense that needs to be checked. There are many plagiarism detection systems such as turn-it-in that has been developed to provide these checks. Most, if not all, discard the figures and charts before checking for plagiarism. Discarding the figures and charts result in look holes that people can take advantage. That means people can plagiarize figures and charts easily without the current plagiarism systems detecting it. There are very few papers which talks about flowcharts plagiarism detection. Therefore, there is a need to develop a system that will detect plagiarism in figures and charts.

Keywords: flowchart, multimedia retrieval, figures similarity, image comparison, figure retrieval

Procedia PDF Downloads 461
4567 Resilience in Patients with Chronic Kidney Disease in Hemodialysis

Authors: Gomes C. C. Izabel, Lanzotti B. Rafaela, Orlandi S. Fabiana

Abstract:

Chronic Kidney Disease is considered a serious public health problem. The exploitation of resilience has been guided by studies conducted in various contexts, especially in hemodialysis, since the impact of diagnosis and restrictions produced during the treatment process because, despite advances in treatment, remains the stigma of the disease and the feeling of pain, hopelessness, low self-esteem and disability. The objective was to evaluate the level of resilience of patients in chronic renal dialysis. This is a descriptive, correlational, cross and quantitative research. The sample consisted of 100 patients from a Renal Replacement Therapy Unit in the countryside of São Paulo. For data collection were used the characterization instrument of Participants and the Resilience Scale. There was a predominance of males (70.0%) were Caucasian (45.0%) and had completed elementary education (34.0%). The average score obtained through the Resilience Scale was 131.3 (± 20.06) points. The resiliency level submitted may be considered satisfactory. It is expected that this study will assist in the preparation of programs and actions in order to avoid possible situations of crises faced by chronic renal patients.

Keywords: hemodialysis units, renal dialysis, renal insufficiency chronic, resilience psychological

Procedia PDF Downloads 277
4566 Finite Element Simulation of Deep Drawing Process to Minimize Earing

Authors: Pawan S. Nagda, Purnank S. Bhatt, Mit K. Shah

Abstract:

Earing defect in drawing process is highly undesirable not only because it adds on an additional trimming operation but also because the uneven material flow demands extra care. The objective of this work is to study the earing problem in the Deep Drawing of circular cup and to optimize the blank shape to reduce the earing. A finite element model is developed for 3-D numerical simulation of cup forming process in ABAQUS. Extra-deep-drawing (EDD) steel sheet has been used for simulation. Properties and tool design parameters were used as input for simulation. Earing was observed in the simulated cup and it was measured at various angles with respect to rolling direction. To reduce the earing defect initial blank shape was modified with the help of anisotropy coefficient. Modified blanks showed notable reduction in earing.

Keywords: anisotropy, deep drawing, earing, finite element simulation

Procedia PDF Downloads 370
4565 Thermal Performance of Radial Heat Sinks for LED Applications

Authors: Jongchul Park, Chan Byon

Abstract:

In this study, the thermal performance of radial heat sinks for LED applications is investigated numerically and experimentally. The effect of geometrical parameters such as inner radius, fin height, fin length, and fin spacing, as well as the Elenbaas number, is considered. In addition, the effects of augmentation of concentric ring, perforation, and duct are extensively explored in order to enhance the thermal performance of conventional radial heat sink. The results indicate that the Elenbaas number and the fin radius have a significant effect on the thermal performance of the heat sink. The concentric ring affects the performance much, but the degree of affection is highly dependent on the orientation. The perforation always brings about higher thermal performance. The duct can effectively prevent the bypass of the natural convection flow, which in turn reduces the thermal resistance of the radial heat sink significantly.

Keywords: heat transfer, radial heat sink, LED, Elenbaas

Procedia PDF Downloads 401
4564 Evaluation of Multi-Sectoral Schistosomiasis Control in Indonesia

Authors: Hayani Anastasia, Junus Widjaja, Anis Nur Widayati

Abstract:

In Indonesia, schistosomiasis is caused by Schistosoma japonicum with Oncomelania hupensis lindoensis as the intermediate host. Schistosomiasis can infect humans and all species of mammals. In order to achieve schistosomiasis elimination by 2020, schistosomiasis control, including environmental management, has been carried out by multi-sector. A cross-sectional study was conducted in 2018 to evaluate the multi-sectoral schistosomiasis control program. Data were collected by depth interviews of stakeholders, stool surveys, snail surveys, observation, and document reviews. About 53.6% of control programs in the schistosomiasis control roadmap were not achieved. The number of foci area found in 2018 are not significantly different compared to before the control programs. Moreover, the prevalence of schistosomiasis in the human was 0-5.1% and in mammals was the range from 0 to 10%. In order to overcome the problems, a policy about schistosomiasis as a priority program in ministries and agencies other than the Ministry of Health is needed. Innovative health promotion with interactive media also needs to be applied. Also, the schistosomiasis work team needs to be more active with the Agency of Regional Development as the leading sector.

Keywords: evaluation, Indonesia, multi-sector, schistosomiasis

Procedia PDF Downloads 130
4563 Machine Learning Driven Analysis of Kepler Objects of Interest to Identify Exoplanets

Authors: Akshat Kumar, Vidushi

Abstract:

This paper identifies 27 KOIs, 26 of which are currently classified as candidates and one as false positives that have a high probability of being confirmed. For this purpose, 11 machine learning algorithms were implemented on the cumulative kepler dataset sourced from the NASA exoplanet archive; it was observed that the best-performing model was HistGradientBoosting and XGBoost with a test accuracy of 93.5%, and the lowest-performing model was Gaussian NB with a test accuracy of 54%, to test model performance F1, cross-validation score and RUC curve was calculated. Based on the learned models, the significant characteristics for confirm exoplanets were identified, putting emphasis on the object’s transit and stellar properties; these characteristics were namely koi_count, koi_prad, koi_period, koi_dor, koi_ror, and koi_smass, which were later considered to filter out the potential KOIs. The paper also calculates the Earth similarity index based on the planetary radius and equilibrium temperature for each KOI identified to aid in their classification.

Keywords: Kepler objects of interest, exoplanets, space exploration, machine learning, earth similarity index, transit photometry

Procedia PDF Downloads 63
4562 PM10 Prediction and Forecasting Using CART: A Case Study for Pleven, Bulgaria

Authors: Snezhana G. Gocheva-Ilieva, Maya P. Stoimenova

Abstract:

Ambient air pollution with fine particulate matter (PM10) is a systematic permanent problem in many countries around the world. The accumulation of a large number of measurements of both the PM10 concentrations and the accompanying atmospheric factors allow for their statistical modeling to detect dependencies and forecast future pollution. This study applies the classification and regression trees (CART) method for building and analyzing PM10 models. In the empirical study, average daily air data for the city of Pleven, Bulgaria for a period of 5 years are used. Predictors in the models are seven meteorological variables, time variables, as well as lagged PM10 variables and some lagged meteorological variables, delayed by 1 or 2 days with respect to the initial time series, respectively. The degree of influence of the predictors in the models is determined. The selected best CART models are used to forecast future PM10 concentrations for two days ahead after the last date in the modeling procedure and show very accurate results.

Keywords: cross-validation, decision tree, lagged variables, short-term forecasting

Procedia PDF Downloads 190
4561 Damage Localization of Deterministic-Stochastic Systems

Authors: Yen-Po Wang, Ming-Chih Huang, Ming-Lian Chang

Abstract:

A scheme integrated with deterministic–stochastic subspace system identification and the method of damage localization vector is proposed in this study for damage detection of structures based on seismic response data. A series of shaking table tests using a five-storey steel frame has been conducted in National Center for Research on Earthquake Engineering (NCREE), Taiwan. Damage condition is simulated by reducing the cross-sectional area of some of the columns at the bottom. Both single and combinations of multiple damage conditions at various locations have been considered. In the system identification analysis, either full or partial observation conditions have been taken into account. It has been shown that the damaged stories can be identified from global responses of the structure to earthquakes if sufficiently observed. In addition to detecting damage(s) with respect to the intact structure, identification of new or extended damages of the as-damaged (ill-conditioned) counterpart has also been studied. The proposed scheme proves to be effective.

Keywords: damage locating vectors, deterministic-stochastic subspace system, shaking table tests, system identification

Procedia PDF Downloads 323
4560 Application of Nanofiltration Membrane for River Nile Water Treatment in Egypt

Authors: Tarek S. Jamil, Ahmed M. Shaban, Eman S. Mansor, Ahmed A. Karim, Azza M. Abdel Aty

Abstract:

In this manuscript, 35 m³/d NF unit was designed and applied for surface water treatment of river Nile water. Intake of Embaba drinking water treatment plant was selected to install that unit at since; it has the lowest water quality index value through the examined 6 sites in greater Cairo area. The optimized operating conditions were feed and permeate flow, 40 and 7 m³/d, feed pressure 2.68 bar and flux rate 37.7 l/m2.h. The permeate water was drinkable according to Egyptian Ministerial decree 458/2007 for the tested parameters (physic-chemical, heavy metals, organic, algal, bacteriological and parasitological). Single and double sand filters were used as pretreatment for NF membranes, but continuous clogging for sand filters moved us to use UF membrane as pretreatment for NF membrane.

Keywords: River Nile, NF membrane, pretreatment, UF membrane, water quality

Procedia PDF Downloads 703
4559 Political Views and Information and Communication Technology (ICT) in Tertiary Institutions in Achieving the Millennium Development Goals (MDGS)

Authors: Perpetual Nwakaego Ibe

Abstract:

The Millennium Development Goals (MDGs), were an integrated project formed to eradicate many unnatural situations the citizens of the third world country may found themselves in. The MDGs, to be a sustainable project for the future depends 100% on the actions of governments, multilateral institutions and civil society. This paper first looks at the political views on the MDGs and relates it to the current electoral situations around the country by underlining the drastic changes over the few months. The second part of the paper presents ICT in tertiary institutions as one of the solutions in terms of the success of the MDGs. ICT is vital in all phases of educational process and development of the cloud connectivity is an added advantage of Information and Communication Technology (ICT) for sharing a common data bank for research purposes among UNICEF, RED CROSS, NPS, INEC, NMIC, and WHO. Finally, the paper concludes with areas that needs twigging and recommendations for the tertiary institutions committed to delivering an ambitious set of goals. A combination of observation, and document materials for data gathering was employed as the methodology for carrying out this research.

Keywords: MDG, ICT, data bank, database

Procedia PDF Downloads 194
4558 Numerical Investigation of Slot Die Coating Based on VOF Method

Authors: Zhidi Lei, Xixi Cai, Jue Ding, Peifen Weng, Xiaowei Li

Abstract:

In the process of preparing thin films by chemical solution method, the uniformity of gel coating has a great influence on the subsequent film thickness. Based on a coating device, the research tracks the interface development of gas-liquid flow by volume of fluid method (VOF). The effects of fluid viscosity and wall wetting property for the shape and position of the coating window are discussed in the process of slot die coating. The result shows that downstream contact lines gets closer to the corner with the increase of fluid viscosity. When the viscosity increases from 0.2Pa∙s to 0.3Pa∙s, 18.2% of the vortex region area will be reduced. With the static contact angle of upper die head surface (θ_sd) increasing, X_u decreased gradually which cause the instability changes of upstream surface. Also, θ_sd increasing brings the reduction of vortex region.

Keywords: film growth, vortex, VOF, slot die coating

Procedia PDF Downloads 367
4557 An Investigation into the Social Determinants of Crowdfunding Effectiveness in developing, non-Western contexts: Some Evidence from Thailand

Authors: Khin Thi Htun, James Jain, Tim Andrews

Abstract:

This study examines the under-researched phenomenon of crowdfunding use and effectiveness in developing non-western markets. More precisely, using an institutional theoretical lens, the research explores the attitudes, motivations, and practice surrounding the initiation, development, and receipt of crowdfunding campaignsin a business context symptomatic of widely dissimilar regulatory, normative cognitive institutional ‘pillars’ to those studied – and utilized in practice - to date. As, in essence, a form of alternative finance, crowdfunding is used primarily to fund a wide range of projects through the securement of small amounts of money from a large pool of investors/participants. Being tied almost inextricably to e-commerce channels, the practice of crowdfunding typically sources its means and communicates the purpose of each venture mainly, though not exclusively, online. The wide range of projects supported to date span social entrepreneurship, community benefits initiatives, creative and artistic endeavors, assistance to disadvantaged social cohorts, and small business start-ups. Adopting a longitudinal, comparative approach, the study reported here embodies an investigation centered on six case start-up campaigns within the Thai societal context, covering a range of fundings calls and cause choices. Data was sourced from a variety of respondents using semi-structured interviews, observation (direct and participant), and company information. Results suggest that the motives and effectiveness of crowdfunding campaigns differ significantly in non-western consumer contexts from the norms that have evolved to date in mature Western contexts(particularly the US and UK). Specifically, whereas data on the different regulatory pressures showed relatively insignificant variation, the results regarding cognitive and, especially, normative dissimilarities between the Thai and US/UK institutional profiles surfaced potentially important differences with far-reaching implications. Particular issuesto emerge from our data concerned consumer motivation in terms of support and engagement with different types of campaigns. This was found to stem from social norms symptomatic of ‘collectivist’ and ‘relations based/particularist’ cultural assistance behavior, in turn, linked to deeply-held societal values regarding interpersonal network (‘in group’) reciprocity. This research serves to refine and extend the limited body of knowledge to date on crowdfunding by exploring the phenomenon in a non-western, non-developed country contextswhere social norms and values differ. This was achieved through uncovering and explicating the effects of cultural dissimilarity on motivation, decision-making, construed ethics, and general engagement with crowdfunding ideas. Implications for theory into e-marketing and cross-cultural marketing, as well as for practitioners seeking to develop effective crowdfunding campaigns in a Southeast Asian cultural environment, are discussed to conclude the paper.

Keywords: crowdfunding, national culture, e-marketing, cross-cultural business

Procedia PDF Downloads 150
4556 Impact of Overall Teaching Program of Anatomy in Learning: A Students Perspective

Authors: Mamatha Hosapatna, Anne D. Souza, Antony Sylvan Dsouza, Vrinda Hari Ankolekar

Abstract:

Our study intends to know the effect of the overall teaching program of Anatomy on a students learning. The advancement of various teaching methodologies in the present era has led to progressive changes in education. A student should be able to correlate well between the theory and practical knowledge attained even in the early years of their education in medicine and should be able to implement the same in patient care. The present study therefore aims to assess the impact the current anatomy teaching program has on a students learning and to what extent is it successful in making the learning program effective. Specific objectives of our study to assess the impact of overall teaching program of Anatomy in a students’ learning. Description of process proposed: A questionnaire will be constructed and the students will be asked to put forth their views regarding the Anatomy teaching program and its method of assessment. Suggestions, if any will also be encouraged to be put forth. Type of study is cross sectional observations. Target population is the first year MBBS students and sample size is 250. Assessment plan is to obtaining students responses using questionnaire. Calculating percentages of the responses obtained. Tabulation of the results will be done.

Keywords: anatomy, observational study questionnaire, observational study, M.B.B.S students

Procedia PDF Downloads 490
4555 Moderating Role of Positive External Factors in Relationship of Abusive Supervision and Knowledge Sharing

Authors: I.Hussain, A. Gulzar

Abstract:

Knowledge sharing is very important in organizations for their future progress and survival. This study investigates the impact of destructive leadership (abusive supervision) on knowledge sharing in employees. Further, the authors want to investigate a context variable (group cohesion) and explore its cross level influence on the relationship of abusive supervision and knowledge sharing. Conservation of resource theory (COR) claims loss of psychological capital (an internal positive resource) in employees due to abusive supervision and hence decrease occurs in knowledge sharing. This study tests psychological capital as mediator and group cohesion as moderator in relationship of abusive supervision and knowledge sharing. Data was collected from 239 respondents from more than 40 different organizations and 50 different groups from all over Pakistan. Results show that abusive supervision has negative effect on knowledge sharing through reduction in psychological capital of employees, and increased group cohesion in employees reduces this negative effect improving psychological capital in employees.

Keywords: abusive supervision, knowledge sharing, psychological capital, group cohesion, conservation of resources

Procedia PDF Downloads 206
4554 Risk Factors of Becoming NEET Youth in Iran: A Machine Learning Approach

Authors: Hamed Rahmani, Wim Groot

Abstract:

The term "youth not in employment, education or training (NEET)" refers to a combination of youth unemployment and school dropout. This study investigates the variables that increase the risk of becoming NEET in Iran. A selection bias-adjusted Probit model was employed using machine learning to identify these risk factors. We used cross-sectional data obtained from the Statistical Centre of Iran and the Ministry of Cooperatives Labour and Social Welfare that was taken from the labour force survey conducted in the spring of 2021. We look at years of education, work experience, housework, the number of children under the age of six in the home, family education, birthplace, and the amount of land owned by households. Results show that hours spent performing domestic chores enhance the likelihood of youth becoming NEET, and years of education and years of potential work experience decrease the chance of being NEET. The findings also show that female youth born in cities were less likely than those born in rural regions to become NEET.

Keywords: NEET youth, probit, CART, machine learning, unemployment

Procedia PDF Downloads 102
4553 Rheological Properties of Thermoresponsive Poly(N-Vinylcaprolactam)-g-Collagen Hydrogel

Authors: Serap Durkut, A. Eser Elcin, Y. Murat Elcin

Abstract:

Stimuli-sensitive polymeric hydrogels have received extensive attention in the biomedical field due to their sensitivity to physical and chemical stimuli (temperature, pH, ionic strength, light, etc.). This study describes the rheological properties of a novel thermoresponsive poly(N-vinylcaprolactam)-g-collagen hydrogel. In the study, we first synthesized a facile and novel synthetic carboxyl group-terminated thermo-responsive poly(N-vinylcaprolactam)-COOH (PNVCL-COOH) via free radical polymerization. Further, this compound was effectively grafted with native collagen, by utilizing the covalent bond between the carboxylic acid groups at the end of the chains and amine groups of the collagen using cross-linking agent (EDC/NHS), forming PNVCL-g-Col. Newly-formed hybrid hydrogel displayed novel properties, such as increased mechanical strength and thermoresponsive characteristics. PNVCL-g-Col showed low critical solution temperature (LCST) at 38ºC, which is very close to the body temperature. Rheological studies determine structural–mechanical properties of the materials and serve as a valuable tool for characterizing. The rheological properties of hydrogels are described in terms of two dynamic mechanical properties: the elastic modulus G′ (also known as dynamic rigidity) representing the reversible stored energy of the system, and the viscous modulus G″, representing the irreversible energy loss. In order to characterize the PNVCL-g-Col, the rheological properties were measured in terms of the function of temperature and time during phase transition. Below the LCST, favorable interactions allowed the dissolution of the polymer in water via hydrogen bonding. At temperatures above the LCST, PNVCL molecules within PNVCL-g-Col aggregated due to dehydration, causing the hydrogel structure to become dense. When the temperature reached ~36ºC, both the G′ and G″ values crossed over. This indicates that PNVCL-g-Col underwent a sol-gel transition, forming an elastic network. Following temperature plateau at 38ºC, near human body temperature the sample displayed stable elastic network characteristics. The G′ and G″ values of the PNVCL-g-Col solutions sharply increased at 6-9 minute interval, due to rapid transformation into gel-like state and formation of elastic networks. Copolymerization with collagen leads to an increase in G′, as collagen structure contains a flexible polymer chain, which bestows its elastic properties. Elasticity of the proposed structure correlates with the number of intermolecular cross-links in the hydrogel network, increasing viscosity. However, at 8 minutes, G′ and G″ values sharply decreased for pure collagen solutions due to the decomposition of the elastic and viscose network. Complex viscosity is related to the mechanical performance and resistance opposing deformation of the hydrogel. Complex viscosity of PNVCL-g-Col hydrogel was drastically changed with temperature and the mechanical performance of PNVCL-g-Col hydrogel network increased, exhibiting lesser deformation. Rheological assessment of the novel thermo-responsive PNVCL-g-Col hydrogel, exhibited that the network has stronger mechanical properties due to both permanent stable covalent bonds and physical interactions, such as hydrogen- and hydrophobic bonds depending on temperature.

Keywords: poly(N-vinylcaprolactam)-g-collagen, thermoresponsive polymer, rheology, elastic modulus, stimuli-sensitive

Procedia PDF Downloads 239
4552 Enhanced Cell Adhesion on PMMA by Radio Frequency Oxygen Plasma Treatment

Authors: Fatemeh Rezaei, Babak Shokri

Abstract:

In this study, PMMA films are modified by oxygen plasma treatment for biomedical applications. The plasma generator is capacitively coupled radio frequency (13.56 MHz) power source. The oxygen pressure and gas flow rate are kept constant at 40 mTorr and 30 sccm, respectively and samples are treated for 2 minutes. Hydrophilicity and biocompatibility of PMMA films are studied before and after treatments in different applied powers (10-80 W). In order to monitor the plasma process, the optical emission spectroscopy is used. The wettability and cellular response of samples are investigated by water contact angle (WCA) analysis and MTT assay, respectively. Also, surface free energy (SFE) variations are studied based on the contact angle measurements of three liquids. It is found that RF oxygen plasma treatment enhances the biocompatibility and also hydrophilicity of PMMA films.

Keywords: cellular response, hydrophilicity, MTT assay, PMMA, RF plasma

Procedia PDF Downloads 664
4551 Forming-Free Resistive Switching Effect in ZnₓTiᵧHfzOᵢ Nanocomposite Thin Films for Neuromorphic Systems Manufacturing

Authors: Vladimir Smirnov, Roman Tominov, Vadim Avilov, Oleg Ageev

Abstract:

The creation of a new generation micro- and nanoelectronics elements opens up unlimited possibilities for electronic devices parameters improving, as well as developing neuromorphic computing systems. Interest in the latter is growing up every year, which is explained by the need to solve problems related to the unstructured classification of data, the construction of self-adaptive systems, and pattern recognition. However, for its technical implementation, it is necessary to fulfill a number of conditions for the basic parameters of electronic memory, such as the presence of non-volatility, the presence of multi-bitness, high integration density, and low power consumption. Several types of memory are presented in the electronics industry (MRAM, FeRAM, PRAM, ReRAM), among which non-volatile resistive memory (ReRAM) is especially distinguished due to the presence of multi-bit property, which is necessary for neuromorphic systems manufacturing. ReRAM is based on the effect of resistive switching – a change in the resistance of the oxide film between low-resistance state (LRS) and high-resistance state (HRS) under an applied electric field. One of the methods for the technical implementation of neuromorphic systems is cross-bar structures, which are ReRAM cells, interconnected by cross data buses. Such a structure imitates the architecture of the biological brain, which contains a low power computing elements - neurons, connected by special channels - synapses. The choice of the ReRAM oxide film material is an important task that determines the characteristics of the future neuromorphic system. An analysis of literature showed that many metal oxides (TiO2, ZnO, NiO, ZrO2, HfO2) have a resistive switching effect. It is worth noting that the manufacture of nanocomposites based on these materials allows highlighting the advantages and hiding the disadvantages of each material. Therefore, as a basis for the neuromorphic structures manufacturing, it was decided to use ZnₓTiᵧHfzOᵢ nanocomposite. It is also worth noting that the ZnₓTiᵧHfzOᵢ nanocomposite does not need an electroforming, which degrades the parameters of the formed ReRAM elements. Currently, this material is not well studied, therefore, the study of the effect of resistive switching in forming-free ZnₓTiᵧHfzOᵢ nanocomposite is an important task and the goal of this work. Forming-free nanocomposite ZnₓTiᵧHfzOᵢ thin film was grown by pulsed laser deposition (Pioneer 180, Neocera Co., USA) on the SiO2/TiN (40 nm) substrate. Electrical measurements were carried out using a semiconductor characterization system (Keithley 4200-SCS, USA) with W probes. During measurements, TiN film was grounded. The analysis of the obtained current-voltage characteristics showed a resistive switching from HRS to LRS resistance states at +1.87±0.12 V, and from LRS to HRS at -2.71±0.28 V. Endurance test shown that HRS was 283.21±32.12 kΩ, LRS was 1.32±0.21 kΩ during 100 measurements. It was shown that HRS/LRS ratio was about 214.55 at reading voltage of 0.6 V. The results can be useful for forming-free nanocomposite ZnₓTiᵧHfzOᵢ films in neuromorphic systems manufacturing. This work was supported by RFBR, according to the research project № 19-29-03041 mk. The results were obtained using the equipment of the Research and Education Center «Nanotechnologies» of Southern Federal University.

Keywords: nanotechnology, nanocomposites, neuromorphic systems, RRAM, pulsed laser deposition, resistive switching effect

Procedia PDF Downloads 127
4550 Identification of Shocks from Unconventional Monetary Policy Measures

Authors: Margarita Grushanina

Abstract:

After several prominent central banks including European Central Bank (ECB), Federal Reserve System (Fed), Bank of Japan and Bank of England employed unconventional monetary policies in the aftermath of the financial crisis of 2008-2009 the problem of identification of the effects from such policies became of great interest. One of the main difficulties in identification of shocks from unconventional monetary policy measures in structural VAR analysis is that they often are anticipated, which leads to a non-fundamental MA representation of the VAR model. Moreover, the unconventional monetary policy actions may indirectly transmit to markets information about the future stance of the interest rate, which raises a question of the plausibility of the assumption of orthogonality between shocks from unconventional and conventional policy measures. This paper offers a method of identification that takes into account the abovementioned issues. The author uses factor-augmented VARs to increase the information set and identification through heteroskedasticity of error terms and rank restrictions on the errors’ second moments’ matrix to deal with the cross-correlation of the structural shocks.

Keywords: factor-augmented VARs, identification through heteroskedasticity, monetary policy, structural VARs

Procedia PDF Downloads 344
4549 Spatial-Temporal Awareness Approach for Extensive Re-Identification

Authors: Tyng-Rong Roan, Fuji Foo, Wenwey Hseush

Abstract:

Recent development of AI and edge computing plays a critical role to capture meaningful events such as detection of an unattended bag. One of the core problems is re-identification across multiple CCTVs. Immediately following the detection of a meaningful event is to track and trace the objects related to the event. In an extensive environment, the challenge becomes severe when the number of CCTVs increases substantially, imposing difficulties in achieving high accuracy while maintaining real-time performance. The algorithm that re-identifies cross-boundary objects for extensive tracking is referred to Extensive Re-Identification, which emphasizes the issues related to the complexity behind a great number of CCTVs. The Spatial-Temporal Awareness approach challenges the conventional thinking and concept of operations which is labor intensive and time consuming. The ability to perform Extensive Re-Identification through a multi-sensory network provides the next-level insights – creating value beyond traditional risk management.

Keywords: long-short-term memory, re-identification, security critical application, spatial-temporal awareness

Procedia PDF Downloads 108
4548 Predicting Trapezoidal Weir Discharge Coefficient Using Evolutionary Algorithm

Authors: K. Roushanger, A. Soleymanzadeh

Abstract:

Weirs are structures often used in irrigation techniques, sewer networks and flood protection. However, the hydraulic behavior of this type of weir is complex and difficult to predict accurately. An accurate flow prediction over a weir mainly depends on the proper estimation of discharge coefficient. In this study, the Genetic Expression Programming (GEP) approach was used for predicting trapezoidal and rectangular sharp-crested side weirs discharge coefficient. Three different performance indexes are used as comparing criteria for the evaluation of the model’s performances. The obtained results approved capability of GEP in prediction of trapezoidal and rectangular side weirs discharge coefficient. The results also revealed the influence of downstream Froude number for trapezoidal weir and upstream Froude number for rectangular weir in prediction of the discharge coefficient for both of side weirs.

Keywords: discharge coefficient, genetic expression programming, trapezoidal weir

Procedia PDF Downloads 382
4547 Algorithm Research on Traffic Sign Detection Based on Improved EfficientDet

Authors: Ma Lei-Lei, Zhou You

Abstract:

Aiming at the problems of low detection accuracy of deep learning algorithm in traffic sign detection, this paper proposes improved EfficientDet based traffic sign detection algorithm. Multi-head self-attention is introduced in the minimum resolution layer of the backbone of EfficientDet to achieve effective aggregation of local and global depth information, and this study proposes an improved feature fusion pyramid with increased vertical cross-layer connections, which improves the performance of the model while introducing a small amount of complexity, the Balanced L1 Loss is introduced to replace the original regression loss function Smooth L1 Loss, which solves the problem of balance in the loss function. Experimental results show, the algorithm proposed in this study is suitable for the task of traffic sign detection. Compared with other models, the improved EfficientDet has the best detection accuracy. Although the test speed is not completely dominant, it still meets the real-time requirement.

Keywords: convolutional neural network, transformer, feature pyramid networks, loss function

Procedia PDF Downloads 91
4546 Advanced Catechol-Modified Chitosan Hydrogels with the Inducement of Iron (III) Ion at Acidic Condition

Authors: Ngoc Quang Nguyen, Daewon Sohn

Abstract:

Chitosan (CS) is a natural polycationic polysaccharide and pH-sensitive polymer with incomplete deacetylation from claiming chitin. It is also a guaranteeing material in terms of pharmaceutical, chemical, and sustenance industry due to its exceptional structure (reactive –OH and –NH2 groups). In this study, a catechol-functionalized chitosan (CCS, for an eminent level for substitution) was synthesized and propelled by marine mussel cuticles in place on research those intricate connections between Fe³⁺ and catechol under acidic conditions. The ratios of catechol, chitosan and other reagents decide the structure of the hydrogel. The gel formation is then well-maintained by dual cross-linking through electrostatic interactions between Fe³⁺ and CCS and covalent catechol-coupling-based coordinate bonds. The hydrogels showed enhanced cohesiveness and shock-absorbing properties with increasing pH due to coordinate bonds inspired by mussel byssal threads. Thus, the gelation time, rheological properties, UV-vis and ¹H-Nuclear Magnetic Resonance spectroscopy, and the morphologic aspects were elucidated to describe those crosslinking components and the physical properties of the chitosan backbones and hydrogel frameworks.

Keywords: catechol, chitosan, iron ion, gelation, hydrogel

Procedia PDF Downloads 137
4545 Association of Photosynthetic Pigment with Oceanic Physical Parameters in the North-eastern Bay of Bengal

Authors: Saif Khan Sunny, Md. Masud-ul-alam

Abstract:

This study presents the association of photosynthetic pigment: chlorophyll-a (chl-a) and physical parameters: sea surface temperature (SST), dissolved oxygen (DO), sea surface salinity (SSS), and total dissolved solids (TDS) in the northeastern Bay of Bengal. At 15 sampling stations in the bay near the eastern coast of Teknaf, photosynthetic pigment and environmental variables were measured for surface water where acetone extraction was used for ch-a. Samples of seawater were taken in March 2021, where chlorophyll-a content varies from 0.554 to 9.696 mg/m3 in surface water over the sampling site. Higher concentrations may be attributable to the nutrient supply of hatcheries and the delivery of fluvial input. The observed SST, DO, SSS, and TDS in the north-eastern Bay of Bengal are 26.65 to 28.6 °C, 6.26 to 8.03 mg/l, 29.3 to 33.1 PSU, and 22.4 to 25.3 ppm, respectively. Temperature and chl-a had a positive association (0.18), according to an analysis of the cross-correlation matrix. Again, a negative correlation (0.34) between dissolved oxygen and temperature is significant at p < 0.05. Total dissolved solids and dissolved oxygen have a significant negative correlation (0.70) where p is < 0.001.

Keywords: photosynthetic pigment, nutrient supply, chlorophyll, physical parameters

Procedia PDF Downloads 81
4544 Fiber Orientation Measurements in Reinforced Thermoplastics

Authors: Ihsane Modhaffar

Abstract:

Fiber orientation is essential for the physical properties of composite materials. The theoretical parameters of a given reinforcement are usually known and widely used to predict the behavior of the material. In this work, we propose an image processing approach to estimate true principal directions and fiber orientation during injection molding processes of short fiber reinforced thermoplastics. Generally, a group of fibers are described in terms of probability distribution function or orientation tensor. Numerical techniques for the prediction of fiber orientation are also considered for concentrated situations. The flow was considered to be incompressible, and behave as Newtonian fluid containing suspensions of short-fibers. The governing equations, of this problem are: the continuity, the momentum and the energy. The obtained results were compared to available experimental findings. A good agreement between the numerical results and the experimental data was achieved.

Keywords: injection, composites, short-fiber reinforced thermoplastics, fiber orientation, incompressible fluid, numerical simulation

Procedia PDF Downloads 526
4543 Telemedicine for Substance-Related Disorders: A Patient Satisfaction Survey among Individuals in Argentina

Authors: Badino Manuel, Farias Maria Alejandra

Abstract:

Telemedicine (TM) has the potential to develop efficient and cost-effective means for delivering quality health care services and outcomes, showing equal or, in some cases, better results than in-person treatment. To analyze patient satisfaction with the use of TM becomes relevant because this can affect the results of treatment and the adherence to it. The aim is to assess patient satisfaction with telemedicine for treating substance-related disorders in a mental health service in Córdoba, Argentina. A descriptive cross-sectional study was conducted among patients with substance-related disorders (N=115). A patient satisfaction survey was conducted from December 2021 to March 2022. For a total of 115 participants, 59,1% were male, 38,3% were female and 2,6% non-binary. In relation to educational status, 40% finished university, 39,1% high school, and 20,9 % only primary school. Regarding age, 4,3 % were young, 92,2% were adults, and 3,5% were elderly. Regarding TM treatment, 95,7% reported being satisfied. Furthermore, 85,2% of users declared that they would continueTM treatment, and 14,8% said that they would not resume TM treatment. To conclude, high levels of patient satisfaction contributes to the continuity of TM modality.

Keywords: telemedicine, mental health, substance-related disorders, patient satisfaction

Procedia PDF Downloads 105
4542 Theoretical Stress-Strain Model for Confined Concrete by Rectangular Reinforcement

Authors: Mizam Dogan, Hande Gökdemir

Abstract:

In reinforced concrete elements, reinforcement steel bars are placed in concrete both longitudinal and lateral directions. The lateral reinforcement (called as confinement) which is used for confining circular RC elements is in a spiral shape. If the cross section of RC element is rectangular, stirrups should be rectangular too. At very high compressive stresses concrete will reach its limit strain value and therefore concrete outside the lateral reinforcement, which is not confined, will crush and start to spell. At this stage, concrete core of the RC element tries to expand laterally as a reason of high Poisson’s ratio value of concrete. Such a deformation is prevented by the lateral reinforcement which applies lateral passive pressure on concrete. At very high compressive stresses, the strength of reinforced column member rises to four times σ 2. This increase in strength of member is related to the properties of rectangular stirrups. In this paper, effect of stirrup step spacing to column behavior is calculated and presented confined concrete model is proved by numerical solutions.

Keywords: confined concrete, concrete column, stress-strain, stirrup, solid, frame

Procedia PDF Downloads 444
4541 The Twin Terminal of Pedestrian Trajectory Based on City Intelligent Model (CIM) 4.0

Authors: Chen Xi, Lao Xuerui, Li Junjie, Jiang Yike, Wang Hanwei, Zeng Zihao

Abstract:

To further promote the development of smart cities, the microscopic "nerve endings" of the City Intelligent Model (CIM) are extended to be more sensitive. In this paper, we develop a pedestrian trajectory twin terminal based on the CIM and CNN technology. It also uses 5G networks, architectural and geoinformatics technologies, convolutional neural networks, combined with deep learning networks for human behaviour recognition models, to provide empirical data such as 'pedestrian flow data and human behavioural characteristics data', and ultimately form spatial performance evaluation criteria and spatial performance warning systems, to make the empirical data accurate and intelligent for prediction and decision making.

Keywords: urban planning, urban governance, CIM, artificial intelligence, convolutional neural network

Procedia PDF Downloads 129
4540 Epidemiological Investigation of Abortion in Ewes in Algeria

Authors: Laatra Zemmouri, Said Boukhechem, Samia Haffaf, Mohamed Lafri

Abstract:

A study was conducted in order to determine the prevalence and risk factors associated with abortion in ewes in the region of M’sila, located in central-eastern Algeria. A questionnaire was carried out to obtain information about the occurrence of abortion, sheep housing conditions, vaccination, feeding and management practices, and whether the farmers kept other livestock. This cross-sectional study was conducted for 36 months (between 2016 and 2019). A total of 71 sheep flocks were visited. Among 8168 ewes, we recorded 734 (8.99%) abortions and 3861 lambings. The risk factor analysis using multivariable logistic regression showed an association between abortion and vaccination against brucellosis (CI 95%= 2,76-1,35; p<0,001). Abortion decreased when dogs are owned (CI 95%= 0,36-0,84; p= 0.006), however, abortion increased with the presence of cats in farms (CI 95%= 1,24-2,8; p=0.003). There was a significant association between abortion and keeping goats (CI 95%= 1,18-2,40; p= 0.004), bovins (CI 95%= 0,3-0,68; p<0,001) and poultry CI 95%= 0,39-0,77; p= 0.001) in farms. Through this study, it is noticed that a strong association between the occurrence of abortion and estrus synchronization, stillbirth occurrence, and feed supplementation (p<0.05). Identification of the causes of abortion is an important task to reduce foetal losses and to improve livestock productivity.

Keywords: abortion, ewes, questionnaire, risk factors

Procedia PDF Downloads 219