Search results for: thermal response parameter (TRP)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10128

Search results for: thermal response parameter (TRP)

2808 Assessment of Rock Masses Performance as a Support of Lined Rock Cavern for Isothermal Compressed Air Energy Storage

Authors: Vathna Suy, Ki-Il Song

Abstract:

In order to store highly pressurized gas such as an isothermal compressed air energy storage, Lined Rock Caverns (LRC) are constructed underground and supported by layers of concrete, steel and rock masses. This study aims to numerically investigate the performance of rock masses which serve as a support of Lined Rock Cavern subjected to high cyclic pressure loadings. FLAC3D finite different software is used for the simulation since the software can effectively model the behavior of concrete lining and steel plate with its built-in structural elements. Cyclic pressure loadings are applied onto the inner surface of the cavern which then transmitted to concrete, steel and eventually to the surrounding rock masses. Changes of stress and strain are constantly monitored throughout all the process of loading operations. The results at various monitoring locations are then extracted and analyzed to assess the response of the rock masses, specifically on its ability to absorb energy during loadings induced by the changes of cyclic pressure loadings inside the cavern. By analyzing the obtained data of stress-strain relation and taking into account the behavior of materials under the effect of strain-dependency, conclusions on the performance of rock masses subjected to high cyclic loading conditions are drawn.

Keywords: cyclic loading, FLAC3D, lined rock cavern (LRC), strain-dependency

Procedia PDF Downloads 233
2807 A Bayesian Hierarchical Poisson Model with an Underlying Cluster Structure for the Analysis of Measles in Colombia

Authors: Ana Corberan-Vallet, Karen C. Florez, Ingrid C. Marino, Jose D. Bermudez

Abstract:

In 2016, the Region of the Americas was declared free of measles, a viral disease that can cause severe health problems. However, since 2017, measles has reemerged in Venezuela and has subsequently reached neighboring countries. In 2018, twelve American countries reported confirmed cases of measles. Governmental and health authorities in Colombia, a country that shares the longest land boundary with Venezuela, are aware of the need for a strong response to restrict the expanse of the epidemic. In this work, we apply a Bayesian hierarchical Poisson model with an underlying cluster structure to describe disease incidence in Colombia. Concretely, the proposed methodology provides relative risk estimates at the department level and identifies clusters of disease, which facilitates the implementation of targeted public health interventions. Socio-demographic factors, such as the percentage of migrants, gross domestic product, and entry routes, are included in the model to better describe the incidence of disease. Since the model does not impose any spatial correlation at any level of the model hierarchy, it avoids the spatial confounding problem and provides a suitable framework to estimate the fixed-effect coefficients associated with spatially-structured covariates.

Keywords: Bayesian analysis, cluster identification, disease mapping, risk estimation

Procedia PDF Downloads 138
2806 Improved Wearable Monitoring and Treatment System for Parkinson’s Disease

Authors: Bulcha Belay Etana, Benny Malengier, Janarthanan Krishnamoorthy, Timothy Kwa, Lieva VanLangenhove

Abstract:

Electromyography measures the electrical activity of muscles using surface electrodes or needle electrodes to monitor various disease conditions. Recent developments in the signal acquisition of electromyograms using textile electrodes facilitate wearable devices, enabling patients to monitor and control their health status outside of healthcare facilities. Here, we have developed and tested wearable textile electrodes to acquire electromyography signals from patients suffering from Parkinson’s disease and incorporated a feedback-control system to relieve muscle cramping through thermal stimulus. In brief, the textile electrodes made of stainless steel was knitted into a textile fabric as a sleeve, and their electrical characteristic, such as signal-to-noise ratio, was compared with traditional electrodes. To relieve muscle cramping, a heating element made of stainless-steel conductive yarn sewn onto cotton fabric, coupled with a vibration system, was developed. The system integrated a microcontroller and a Myoware muscle sensor to activate the heating element as well as the vibration motor when cramping occurs, and at the same time, the element gets deactivated when the muscle cramping subsides. An optimum therapeutic temperature of 35.5 °C is regulated by continuous temperature monitoring to deactivate the heating system when this threshold value is reached. The textile electrode exhibited a signal-to-noise ratio of 6.38dB, comparable to that of the traditional electrode’s value of 7.05 dB. For a given 9 V power supply, the rise time was about 6 minutes for the developed heating element to reach an optimum temperature.

Keywords: smart textile system, wearable electronic textile, electromyography, heating textile, vibration therapy, Parkinson’s disease

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2805 Effect of Cabbage and Cauliflower Emitted Volatile Organic Compounds on Foraging Response of Plutella xylostella

Authors: Sumbul Farhat, Pratyay Vaibhav, Sarah Jain, Kapinder Kumar, Archna Kumar

Abstract:

The Diamondback Moth, Plutella xylostella (Linnaeus), is a major pest of cole crops that causes approximately 50% loss in global production. The utilization of inorganic pesticides is reflected in the development of resistance to this pest. Thus, there is a great need for an eco-friendly, sustainable strategy for the control of this pest. Although this pest, several natural enemies are reported worldwide, none of them can control it efficiently. Therefore, a proposed study is planned to understand the Volatile Organic Compounds (VOCs) mediated signaling interaction mechanism of the plant, pest, and natural enemy. For VOCs collection during different deployment stages of Cabbage POI, Green Ball, Pusa Cabbage, Cabbage Local, Snowball 16, Kanchan Plus, Pusa Meghna, Farm Sona Hybrid F1, and Samridhi F1 Hybrid, the Solid-phase microextraction (SPME) method was employed. Characterization of VOCs was conducted by Gas Chromatography-Mass Spectrometry (GC-MS). The impact of collected VOCs was assessed through Y-Tube Bioassays. The results indicate that the Cabbage variety Green Ball shows maximum repellency for P. xylostella (-100%). The cues present in this variety may be exploited for efficient management of P. xylostella in the cole crop ecosystem.

Keywords: Plutella xylostella, cole crops, volatile organic compounds, GC-MS, Green Ball

Procedia PDF Downloads 107
2804 Seismic Response of Large-Scale Rectangular Steel-Plate Concrete Composite Shear Walls

Authors: Siamak Epackachi, Andrew S. Whittaker, Amit H. Varma

Abstract:

An experimental program on steel-plate concrete (SC) composite shear walls was executed in the NEES laboratory at the University at Buffalo. Four large-size specimens were tested under displacement-controlled cyclic loading. The design variables considered in the testing program included wall thickness, reinforcement ratio, and faceplate slenderness ratio. The aspect ratio (height-to-length) of the four walls was 1.0. Each SC wall was installed on top of a re-usable foundation block. A bolted baseplate to RC foundation connection was used for all four walls. The walls were identified to be flexure-critical. This paper presents the damage to SC walls at different drift ratios, the cyclic force-displacement relationships, energy dissipation and equivalent viscous damping ratios, the strain and stress fields in the steel faceplates and the contribution of the steel faceplates to the total shear load, the variation of vertical strain in the steel faceplates along the length of the wall, near the base, at different drift ratios, the contributions of shear, flexure, and base rotation to the total lateral displacement, the displacement ductility of the SC walls, and the cyclic secant stiffness of the four SC walls.

Keywords: steel-plate composite shear wall, safety-related nuclear structure, flexure-critical wall, cyclic loading

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2803 Visual Text Analytics Technologies for Real-Time Big Data: Chronological Evolution and Issues

Authors: Siti Azrina B. A. Aziz, Siti Hafizah A. Hamid

Abstract:

New approaches to analyze and visualize data stream in real-time basis is important in making a prompt decision by the decision maker. Financial market trading and surveillance, large-scale emergency response and crowd control are some example scenarios that require real-time analytic and data visualization. This situation has led to the development of techniques and tools that support humans in analyzing the source data. With the emergence of Big Data and social media, new techniques and tools are required in order to process the streaming data. Today, ranges of tools which implement some of these functionalities are available. In this paper, we present chronological evolution evaluation of technologies for supporting of real-time analytic and visualization of the data stream. Based on the past research papers published from 2002 to 2014, we gathered the general information, main techniques, challenges and open issues. The techniques for streaming text visualization are identified based on Text Visualization Browser in chronological order. This paper aims to review the evolution of streaming text visualization techniques and tools, as well as to discuss the problems and challenges for each of identified tools.

Keywords: information visualization, visual analytics, text mining, visual text analytics tools, big data visualization

Procedia PDF Downloads 386
2802 Lignin Pyrolysis to Value-Added Chemicals: A Mechanistic Approach

Authors: Binod Shrestha, Sandrine Hoppe, Thierry Ghislain, Phillipe Marchal, Nicolas Brosse, Anthony Dufour

Abstract:

The thermochemical conversion of lignin has received an increasing interest in the frame of different biorefinery concepts for the production of chemicals or energy. It is needed to better understand the physical and chemical conversion of lignin for feeder and reactor designs. In-situ rheology reveals the viscoelastic behaviour of lignin upon thermal conversion. The softening, re-solidification (char formation), swelling and shrinking behaviours are quantified during pyrolysis in real-time [1]. The in-situ rheology of an alkali lignin (Protobind 1000) was conducted in high torque controlled strain rheometer from 35°C to 400°C with a heating rate of 5°C.min-1. The swelling, through glass phase transition overlapped with depolymerization, and solidification (crosslinking and “char” formation) are two main phenomena observed during lignin pyrolysis. The onset of temperatures for softening and solidification for this lignin has been found to be 141°C and 248°C respectively. An ex-situ characterization of lignin/char residues obtained at different temperatures after quenching in the rheometer gives a clear understanding of the pathway of lignin degradation. The lignin residues were sampled from the mid-point temperatures of the softening range and solidification range to study the chemical transformations undergoing. Elemental analysis, FTIR and solid state NMR were conducted after quenching the solid residues (lignin/char). The quenched solid was also extracted by suitable solvent and followed by acetylation and GPC-UV analysis. The combination of 13C NMR and GPC-UV reveals the depolymerization followed by crosslinking of lignin/char. NMR and FTIR provide the evolution of functional moieties upon temperature. Physical and chemical mechanisms occurring during lignin pyrolysis are accounted in this study. Thanks to all these complementary methods.

Keywords: pyrolysis, bio-chemicals, valorization, mechanism, softening, solidification, cross linking, rheology, spectroscopic methods

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2801 Effect of Probiotics and Vitamin B on Plasma Interferon-Gamma and Interleukin-6 Levels in Active Pulmonary Tuberculosis

Authors: Yulistiani Yulistiani, Zamrotul Izzah, Lintang Bismantara, Wenny Putri Nilamsari, Arif Bachtiar, Budi Suprapti

Abstract:

Interferon-gamma (IFN-γ) and interleukin-6 (IL-6) are pro-inflammatory cytokines, which have the protective immune response against Tuberculosis (TB). Indeed, pro-inflammatory cytokines Mycobacterium tuberculosis antigen-specific CD4+ and CD8+ T cells and NK cells increase the level of production of IFN-γ, a cytokine critical for augmenting the microbicidal activity of phagocytes. On the other hand, M. tuberculosis reduces the effects of IFN-γ by inhibiting the transcription of IFN-γ- responsive genes and by inducing the secretion of IL-6, which inhibits IFN-γ signaling. Probiotics Lactobacillus sp. and Bifidobacterium sp. were known to increase IFN-γ production in vivo, while vitamin B1, B6, and B12 worked on macrophages and releasing cytokines. Therefore, the present study was to evaluate the effect of probiotics and vitamin B supplement on changes of plasma cytokine levels in active pulmonary TB. From October to November 2016, twelve M. tuberculosis-infected patients starting anti-TB drugs were recruited, then divided into two groups. Seven patients were given a combination of probiotics and vitamin B, while five patients were in the control group. Plasma IFN-γ and IL-6 levels were measured by the ELISA kit before and a month after treatment. IFN-γ levels raised in four patients receiving the supplement (P = 0.743), while IL-6 increased in three patients in this group until day 30 of treatment (P = 0.298). Taken together, these results show the promising effect of probiotics and vitamin B on stimulation of IFN-γ and IL-6 production during intensive therapy of TB.

Keywords: interferon-gamma, interleukin-6, probiotic, tuberculosis

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2800 The Role of Vitamin D Supplementation in Augmenting IFN-γ Production in Response to Mycobacterium Tuberculosis Infection: A Randomized Controlled Trial

Authors: Muhammad Imran Hussain, Ramisha Ibtisam, Tayyaba Fatima, Huba Khalid, Ayesha Aziz, Khansa, Adan Sitara, Anam Shahzad, Aymen Jabeen

Abstract:

Vitamin D supports the immune system fight TB by inhibiting Interferon-gamma (IFN-γ) and lowering host inflammation. The purpose of the research was to see if giving the vitamin D supplements to TB patients affected their prognosis. A randomized placebo control study of 200 TB patients was performed among which 106 received 400,000 IU of injectable vitamin D3 and 94 received placebo for 2 doses. Assessment was carried out at the end of every month for 3 months. IFN-γ responses to whole blood stimulation generated by the Mycobacterium tuberculosis sonicate (MTBs) antigen and early secreted and T cell activated 6 kDa (ESAT6) were assessed at 0 and 12 weeks. The statistical analysis used descriptive statistics (mean and standard deviation), Friedman's test and Fisher's test. The vitamin D group gained significantly more weight (+3.90 pounds) and had less persistent lung disease on imaging (1.33 zones vs. 1.84 zones). They also had a 50% decrease in cavity size. Additionally, patients with low baseline serum concentrations of 25-(OH)D had a significant increase in MTB-induced IFN-γ production after taking vitamin D supplements. Vitamin D administration in large amounts can hasten the recovery of TB patients. The findings point is a therapeutically useful activity of Vitamin D's in the management for tuberculosis.

Keywords: tuberculosis, vitamin D, interferon gamma, protein, infection

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2799 Influence of Cucurbitacin-Containing Phytonematicides on Growth of Rough Lemon (Citrus jambhiri)

Authors: Raisibe V. Mathabatha, Phatu W. Mashela, Nehemiah M. Mokgalong

Abstract:

Occasional incidence of phytotoxicity in Nemarioc-BL and Nemafric-AL phytonematicides to crops raises credibility challenges that could negate their registration as commercial products. Responses of plants to phytonematicides are characterized by the existence of stimulation, neutral and inhibition phases, with the mid-point of the former being referred to as the Mean Concentration Stimulation Point (MSCP = Dm + Rh/2). The objective of this study was to determine the MCSP and the overall sensitivity (∑k) of Nemarioc-AL and Nemafric-BL phytonematicides to rough lemon seedling rootstocks using the Curve-fitting Allelochemical Response Dosage (CARD) computer-based model. Two parallel greenhouse experiments were initiated, with seven dilutions of each phytonematicide arranged in a randomised complete block design, replicated nine times. Six-month-old rough lemon seedlings were transplanted into 20-cm-diameter plastic pots, filled with steam-pasteurised river sand (300°C for 3 h) and Hygromix-T growing mixture. Treatments at 0, 2, 4, 8, 16, 32 and 164% dilutions were applied weekly at 300 ml/plant. At 84 days after the treatments, analysis of variance-significant plant variables was subjected to the CARD model to generate appropriate biological indices. Computed MCSP values for Nemarioc-AL and Nemafric-BL phytonematicides on rough lemon were 29 and 38%, respectively, whereas ∑k values were 1 and 0, respectively. At the applied concentrations, rough lemon seedlings were highly sensitive to Nemarioc-AL and Nemafric-BL phytonematicides.

Keywords: crude extracts, cucurbitacins, effective microbes, fruit extracts

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2798 Feasibility of Solar Distillation as Household Water Supply in Saline Zones of Bangladesh

Authors: Md. Rezaul Karim, Md. Ashikur Rahman, Dewan Mahmud Mim

Abstract:

Scarcity of potable water as the result of rapid climate change and saltwater intrusion in groundwater has been a major problem in the coastal regions over the world. In equinoctial countries like Bangladesh, where sunlight is available for more than 10 hours a day, Solar Distillation provides a promising sustainable way for safe drinking water supply in coastal poor households with negligible major cost and difficulty of construction and maintenance. In this paper, two passive type solar stills- a Conventional Single Slope Solar still (CSS) and a Pyramid Solar Sill (PSS) is used and relationship is established between distill water output corresponding to four different factors- temperature, solar intensity, relative humidity and wind speed for Gazipur, Bangladesh. Comparison is analyzed between the two different still outputs for nine months period (January- September) and efficiency is calculated. Later a thermal mathematical model is developed and the distilled water output for Khulna, Bangladesh is computed. Again, difference between the output of the two cities- Gazipur and Khulna is demonstrated and finally an economic analysis is prepared. The distillation output has a positive correlation with temperature and solar intensity, inverse relation with relative humidity and wind speed has nugatory consequence. The maximum output of Conventional Solar Still is obtained 3.8 L/m2/day and Pyramid still is 4.3 L/m2/day for Gazipur and almost 15% more efficiency is found for Pyramid still. Productivity in Khulna is found almost 20% more than Gazipur. Based on economic analysis, taking 10 BDT, per liter, the net profit, benefit cost ratio, payback period all indicates that both stills are feasible but pyramid still is more feasible than Conventional Still. Finally, for a 3-4 member family, area of 4 m2 is suggested for Conventional Still and 3m2 for Pyramid Solar Still.

Keywords: solar distillation, household water supply, saline zones, Bangladesh

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2797 Damage of Laminated Corrugated Sandwich Panels under Inclined Impact Loading

Authors: Muhammad Kamran, Xue Pu, Naveed Ahmed

Abstract:

Sandwich foam structures are efficient in impact energy absorption and making components lightweight; however their efficient use require a detailed understanding of its mechanical response. In this study, the foam core, laminated facings’ sandwich panel with internal triangular rib configuration is impacted by a spherical steel projectile at different angles using ABAQUS finite element package and damage mechanics is studied. Laminated ribs’ structure is sub-divided into three formations; all zeros, all 45 and optimized combination of zeros and 45 degrees. Impact velocity is varied from 250 m/s to 500 m/s with an increment of 50 m/s. The impact damage can significantly demolish the structural integrity and energy absorption due to fiber breakage, matrix cracking, and de-bonding. Macroscopic fracture study of the panel and core along with load-displacement responses and failure modes are the key parameters in the design of smart ballistic resistant structures. Ballistic impact characteristics of panels are studied on different speed, different inclination angles and its dependency on the base, and core materials, ribs formation, and cross-sectional spaces among them are determined. Impact momentum, penetration and kinetic energy absorption data and curves are compiled to predict the first and proximity impact in an effort to enhance the dynamic energy absorption.

Keywords: dynamic energy absorption, proximity impact, sandwich panels, impact momentum

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2796 Enhancement of Mulberry Leaf Yield and Water Productivity in Eastern Dry Zone of Karnataka, India

Authors: Narayanappa Devakumar, Chengalappa Seenappa

Abstract:

The field experiments were conducted during Rabi 2013 and summer 2014 at College of Sericulture, Chintamani, Chickaballapur district, Karnataka, India to find out the response of mulberry to different methods, levels of irrigation and mulching. The results showed that leaf yield and water productivity of mulberry were significantly influenced by different methods, levels of irrigation and mulching. Subsurface drip with lower level of irrigation at 0.8 CPE (Cumulative Pan Evaporation) recorded higher leaf yield and water productivity (42857 kg ha-1 yr-1and 364.41 kg hacm-1) than surface drip with higher level of irrigation at 1.0 CPE (38809 kg ha-1 yr-1 and 264.10 kg hacm-1) and micro spray jet (39931 kg ha-1 yr-1 and 271.83 kg hacm-1). Further, subsurface drip recorded minimum water used to produce one kg of leaf and to earn one rupee of profit (283 L and 113 L) compared to surface drip (390 L and 156 L) and micro spray jet (379 L and 152 L) irrigation methods. Mulberry leaf yield increased and water productivity decreased with increased levels of irrigation. However, these results indicated that irrigation of mulberry with subsurface drip increased leaf yield and water productivity by saving 20% of irrigation water than surface drip and micro spray jet irrigation methods in Eastern Dry Zone (EDZ) of Karnataka.

Keywords: cumulative pan evaporation, mulaberry, subsurface drip irrigation, water productivity

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2795 Blood Ketones as a Point of Care Testing in Paediatric Emergencies

Authors: Geetha Jayapathy, Lakshmi Muthukrishnan, Manoj Kumar Reddy Pulim , Radhika Raman

Abstract:

Introduction: Ketones are the end products of fatty acid metabolism and a source of energy for vital organs such as the brain, heart and skeletal muscles. Ketones are produced in excess when glucose is not available as a source of energy or it cannot be utilized as in diabetic ketoacidosis. Children admitted in the emergency department often have starvation ketosis which is not clinically manifested. Decision on admission of children to the emergency room with subtle signs can be difficult at times. Point of care blood ketone testing can be done at the bedside even in a primary level care setting to supplement and guide us in our management decisions. Hence this study was done to explore the utility of this simple bedside parameter as a supplement in assessing pediatric patients presenting to the emergency department. Objectives: To estimate blood ketones of children admitted in the emergency department. To analyze the significance of blood ketones in various disease conditions. Methods: Blood ketones using point of care testing instrument (ABOTTprecision Xceed Pro meters) was done in patients getting admitted in emergency room and in out-patients (through sample collection centre). Study population: Children aged 1 month to 18 years were included in the study. 250 cases (In-patients) and 250 controls (out-patients) were collected. Study design: Prospective observational study. Data on details of illness and physiological status were documented. Blood ketones were compared between the two groups and all in patients were categorized into various system groups and analysed. Results: Mean blood ketones were high in in-patients ranging from 0 to 7.2, with a mean of 1.28 compared to out-patients ranging from 0 to 1.9 with a mean of 0.35. This difference was statistically significant with a p value < 0.001. In-patients with shock (mean of 4.15) and diarrheal dehydration (mean of 1.85) had a significantly higher blood ketone values compared to patients with other system involvement. Conclusion: Blood ketones were significantly high (above the normal range) in pediatric patients who are sick requiring admission. Patients with various forms of shock had very high blood ketone values as found in diabetic ketoacidosis. Ketone values in diarrheal dehydration were moderately high correlating to the degree of dehydration.

Keywords: admission, blood ketones, paediatric emergencies, point of care testing

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2794 The Impact of Rising Architectural Façade in Improving Terms of the Physical Urban Ambience Inside the Free Space for Urban Fabric - the Street- Case Study the City of Biskra

Authors: Rami Qaoud, Alkama Djamal

Abstract:

When we ask about the impact of rising architectural façade in improving the terms physical urban ambiance inside the free space for urban fabric. Considered as bringing back life and culture values and civilization to these cities. And This will be the theme of this search. Where we have conducted the study about the relationship that connects the empty and full of in the urban fabric in terms of the density construction and the architectural elevation of its façade to street view. In this framework, we adopted in the methodology of this research the technical field experience. And according to three types of Street engineering(H≥2W, H=W, H≤0.5W). Where we conducted a field to raise the values of the physical ambiance according to three main axes of ambiance. The first axe 1 - Thermal ambiance. Where the temperature values were collected, relative humidity, wind speed, temperature of surfaces (the outer wall-ground). The second axe 2- Visual ambiance. Where we took the values of natural lighting levels during the daytime. The third axe 3- Acoustic ambiance . Where we take sound values during the entire day. That experience, which lasted for three consecutive days, and through six stations of measuring, where it has been one measuring station for each type of the street engineering and in two different way street. Through the obtained results and with the comparison of those values. We noticed the difference between this values and the three type of street engineering. Where the difference the calorific values of air equal 4 ° C , in terms of the visual ambiance the difference in the direct lighting natural periods amounted six hours between the three types of street engineering. As well in terms of sound ambience, registered a difference in values of up 15 (db) between the three types. This difference in values indicates The impact of rising architectural façade in improving the physical urban ambiance within the free field - street- for urban fabric.

Keywords: street, physical urban ambience, rising architectural façade, urban fabric

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2793 A Survey of the Sleep-Disturbed Bedroom Environmental Factors and the Occupants Bedroom Windows or Door Opening Behaviors

Authors: Chenxi Liao, Mizuho Akimoto, Mariya Bivolarova, Sekhar Chandra, Xiaojun Fan, Li Lan, Jelle Laverge, Pawel Wargocki

Abstract:

The bedroom environment plays an important role in maintaining good sleep quality, which is vital for humans health and next-day performance. A survey of the sleep-disturbed bedroom environmental factors and the occupants’ bedroom windows (BW) or bedroom door (BD) opening behaviors was launched in the capital region of Denmark in 2020 by an online questionnaire. People were asked if they were disturbed by too warm temperature, too cool temperature, noise, or stuffy air during sleep. Also, they reported their BW or the BD opening behaviors in the morning, afternoon, evening, and during sleep. A total of 512 responses were received. Too warm temperature was reported the most among the four sleep-disturbed factors, following too cool temperature, noise, and stuffy air. Whether or not opening BW or the BD was commonly used to improve or change the bedroom environment. The respondents who were disturbed by too warm temperature during sleep opened BW for a longer time in the morning compared to those who were never disturbed by it (OR, 1.28; 95% CI, 1.01-1.62). Those who were disturbed by too cool temperatures tended to open BW less frequently in the morning (OR, 1.24; 95% CI, 0.97-1.57). They preferred keeping BW open in the whole day if they realized stuffy air disturbing their sleep, although only a few of them still opened BW during sleep. Those who were disturbed by too cool temperature (OR, 0.76; 95% CI, 0.63-0.92) and noise (OR, 0.80; 95% CI, 0.66-0.96) were more likely to sleep with the BD open in a lesser frequency. Opening BW, increasing ventilation rates, could relieve disturbing by stuffy air during sleep, but induced other sleep-disturbed factors such as too cool in winter and noise. Also, opening BW only when people were not sleep was not sufficient to exempt disturbing by stuffy air during sleep. Using mechanical ventilation in bedrooms is necessary to ensure good air quality and meanwhile to avoid thermal discomfort and noise during sleep. Future studies are required to figure out the required flow rate of fresh air of mechanical ventilation during sleep.

Keywords: bedroom environmental, survey, occupants behaviors, windows, door

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2792 Effect of Nanostructure on Hydrogen Embrittlement Resistance of the Severely Deformed 316LN Austenitic Steel

Authors: Frank Jaksoni Mweta, Nozomu Adachi, Yoshikazu Todaka, Hirokazu Sato, Yuta Sato, Hiromi Miura, Masakazu Kobayashi, Chihiro Watanabe, Yoshiteru Aoyagi

Abstract:

Advances in the consumption of hydrogen fuel increase demands of high strength steel pipes and storage tanks. However, high strength steels are highly sensitive to hydrogen embrittlement. Because the introduction of hydrogen into steel during the fabrication process or from the environment is unavoidable, it is essential to improve hydrogen embrittlement resistance of high strength steels through microstructural control. In the present study, the heterogeneous nanostructure with a tensile strength of about 1.8 GPa and the homogeneous nanostructure with a tensile strength of about 2.0 GPa of 316LN steels were generated after 92% heavy cold rolling and high-pressure torsion straining, respectively. The heterogeneous nanostructure is composed of twin domains, shear bands, and lamellar grains. The homogeneous nanostructure is composed of uniformly distributed ultrafine nanograins. The influence of heterogeneous and homogenous nanostructures on the hydrogen embrittlement resistance was investigated. The specimen for each nanostructure was electrochemically charged with hydrogen for 3, 6, 12, and 24 hours, respectively. Under the same hydrogen charging time, both nanostructures show almost the same concentration of the diffusible hydrogen based on the thermal desorption analysis. The tensile properties of the homogenous nanostructure were severely affected by the diffusible hydrogen. However, the diffusible hydrogen shows less impact on the tensile properties of the heterogeneous nanostructure. The difference in embrittlement behavior between the heterogeneous and homogeneous nanostructures was elucidated based on the mechanism of the cracks' growth observed in the tensile fractography. The hydrogen embrittlement was suppressed in the heterogeneous nanostructure because the twin domain became an obstacle for crack growth. The homogeneous nanostructure was not consisting an obstacle such as a twin domain; thus, the crack growth resistance was low in this nanostructure.

Keywords: diffusible hydrogen, heterogeneous nanostructure, homogeneous nanostructure, hydrogen embrittlement

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2791 Amifostine Analogue, Drde-30, Attenuates Radiation-Induced Lung Injury in Mice

Authors: Aastha Arora, Vikas Bhuria, Saurabh Singh, Uma Pathak, Shweta Mathur, Puja P. Hazari, Rajat Sandhir, Ravi Soni, Anant N. Bhatt, Bilikere S. Dwarakanath

Abstract:

Radiotherapy is an effective curative and palliative option for patients with thoracic malignancies. However, lung injury, comprising of pneumonitis and fibrosis, remains a significant clin¬ical complication of thoracic radiation, thus making it a dose-limiting factor. Also, injury to the lung is often reported as part of multi-organ failure in victims of accidental radiation exposures. Radiation induced inflammatory response in the lung, characterized by leukocyte infiltration and vascular changes, is an important contributing factor for the injury. Therefore, countermeasure agents to attenuate radiation induced inflammatory response are considered as an important approach to prevent chronic lung damage. Although Amifostine, the widely used, FDA approved radio-protector, has been found to reduce the radiation induced pneumonitis during radiation therapy of non-small cell lung carcinoma, its application during mass and field exposure is limited due to associated toxicity and ineffectiveness with the oral administration. The amifostine analogue (DRDE-30) overcomes this limitation as it is orally effective in reducing the mortality of whole body irradiated mice. The current study was undertaken to investigate the potential of DRDE-30 to ameliorate radiation induced lung damage. DRDE-30 was administered intra-peritoneally, 30 minutes prior to 13.5 Gy thoracic (60Co-gamma) radiation in C57BL/6 mice. Broncheo- alveolar lavage fluid (BALF) and lung tissues were harvested at 12 and 24 weeks post irradiation for studying inflammatory and fibrotic markers. Lactate dehydrogenase (LDH) leakage, leukocyte count and protein content in BALF were used as parameters to evaluate lung vascular permeability. Inflammatory cell signaling (p38 phosphorylation) and anti-oxidant status (MnSOD and Catalase level) was assessed by Western blot, while X-ray CT scan, H & E staining and trichrome staining were done to study the lung architecture and collagen deposition. Irradiation of the lung increased the total protein content, LDH leakage and total leukocyte count in the BALF, reflecting endothelial barrier dysfunction. These disruptive effects were significantly abolished by DRDE-30, which appear to be linked to the DRDE-30 mediated abrogation of activation of the redox-sensitive pro- inflammatory signaling cascade, the MAPK pathway. Concurrent administration of DRDE-30 with radiation inhibited radiation-induced oxidative stress by strengthening the anti-oxidant defense system and abrogated p38 mitogen-activated protein kinase activation, which was associated with reduced vascular leak and macrophage recruitment to the lungs. Histopathological examination (by H & E staining) of the lung showed radiation-induced inflammation of the lungs, characterized by cellular infiltration, interstitial oedema, alveolar wall thickening, perivascular fibrosis and obstruction of alveolar spaces, which were all reduced by pre-administration of DRDE-30. Structural analysis with X-ray CT indicated lung architecture (linked to the degree of opacity) comparable to un-irradiated mice that correlated well with the lung morphology and reduced collagen deposition. Reduction in the radiation-induced inflammation and fibrosis brought about by DRDE-30 resulted in a profound increase in animal survival (72 % in the combination vs 24% with radiation) observed at the end of 24 weeks following irradiation. These findings establish the potential of the Amifostine analogue, DRDE-30, in reducing radiation induced pulmonary injury by attenuating the inflammatory and fibrotic responses.

Keywords: amifostine, fibrosis, inflammation, lung injury radiation

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2790 Genome-Wide Functional Analysis of Phosphatase in Cryptococcus neoformans

Authors: Jae-Hyung Jin, Kyung-Tae Lee, Yee-Seul So, Eunji Jeong, Yeonseon Lee, Dongpil Lee, Dong-Gi Lee, Yong-Sun Bahn

Abstract:

Cryptococcus neoformans causes cryptococcal meningoencephalitis mainly in immunocompromised patients as well as immunocompetent people. But therapeutic options are limited to treat cryptococcosis. Some signaling pathways including cyclic AMP pathway, MAPK pathway, and calcineurin pathway play a central role in the regulation of the growth, differentiation, and virulence of C. neoformans. To understand signaling networks regulating the virulence of C. neoformans, we selected the 114 putative phosphatase genes, one of the major components of signaling networks, in the genome of C. neoformans. We identified putative phosphatases based on annotation in C. neoformans var. grubii genome database provided by the Broad Institute and National Center for Biotechnology Information (NCBI) and performed a BLAST search of phosphatases of Saccharomyces cerevisiae, Aspergillus nidulans, Candida albicans and Fusarium graminearum to Cryptococcus neoformans. We classified putative phosphatases into 14 groups based on InterPro phosphatase domain annotation. Here, we constructed 170 signature-tagged gene-deletion strains through homologous recombination methods for 91 putative phosphatases. We examined their phenotypic traits under 30 different in vitro conditions, including growth, differentiation, stress response, antifungal resistance and virulence-factor production.

Keywords: human fungal pathogen, phosphatase, deletion library, functional genomics

Procedia PDF Downloads 345
2789 Weighted Data Replication Strategy for Data Grid Considering Economic Approach

Authors: N. Mansouri, A. Asadi

Abstract:

Data Grid is a geographically distributed environment that deals with data intensive application in scientific and enterprise computing. Data replication is a common method used to achieve efficient and fault-tolerant data access in Grids. In this paper, a dynamic data replication strategy, called Enhanced Latest Access Largest Weight (ELALW) is proposed. This strategy is an enhanced version of Latest Access Largest Weight strategy. However, replication should be used wisely because the storage capacity of each Grid site is limited. Thus, it is important to design an effective strategy for the replication replacement task. ELALW replaces replicas based on the number of requests in future, the size of the replica, and the number of copies of the file. It also improves access latency by selecting the best replica when various sites hold replicas. The proposed replica selection selects the best replica location from among the many replicas based on response time that can be determined by considering the data transfer time, the storage access latency, the replica requests that waiting in the storage queue and the distance between nodes. Simulation results utilizing the OptorSim show our replication strategy achieve better performance overall than other strategies in terms of job execution time, effective network usage and storage resource usage.

Keywords: data grid, data replication, simulation, replica selection, replica placement

Procedia PDF Downloads 246
2788 Intelligent Chatbot Generating Dynamic Responses Through Natural Language Processing

Authors: Aarnav Singh, Jatin Moolchandani

Abstract:

The proposed research work aims to build a query-based AI chatbot that can answer any question related to any topic. A chatbot is software that converses with users via text messages. In the proposed system, we aim to build a chatbot that generates a response based on the user’s query. For this, we use natural language processing to analyze the query and some set of texts to form a concise answer. The texts are obtained through web-scrapping and filtering all the credible sources from a web search. The objective of this project is to provide a chatbot that is able to provide simple and accurate answers without the user having to read through a large number of articles and websites. Creating an AI chatbot that can answer a variety of user questions on a variety of topics is the goal of the proposed research project. This chatbot uses natural language processing to comprehend user inquiries and provides succinct responses by examining a collection of writings that were scraped from the internet. The texts are carefully selected from reliable websites that are found via internet searches. This project aims to provide users with a chatbot that provides clear and precise responses, removing the need to go through several articles and web pages in great detail. In addition to exploring the reasons for their broad acceptance and their usefulness across many industries, this article offers an overview of the interest in chatbots throughout the world.

Keywords: Chatbot, Artificial Intelligence, natural language processing, web scrapping

Procedia PDF Downloads 45
2787 Qusai-Solid-State Electrochromic Device Based on PolyMethyl Methacrylate (PMMA)/Succinonitrile Gel Polymer Electrolyte

Authors: Jen-Yuan Wang, Min-Chuan Wang, Der-Jun Jan

Abstract:

Polymer electrolytes can be classified into four major categories, solid polymer electrolytes (SPEs), gel polymer electrolytes (GPEs), polyelectrolytes and composite polymer electrolytes. SPEs suffer from low ionic conductivity at room temperature. The main problems for GPEs are the poor thermal stability and mechanical properties. In this study, a GPE containing PMMA and succinonitrile is prepared to solve the problems mentioned above, and applied to the assembly of a quasi-solid-state electrochromic device (ECD). In the polymer electrolyte, poly(methyl methacrylate) (PMMA) is the polymer matrix and propylene carbonate (PC) is used as the plasticizer. To enhance the mechanical properties of this GPE, succinonitrile (SN) is introduced as the additive. For the electrochromic materials, tungsten oxide (WO3) is used as the cathodic coloring film, which is fabricated by pulsed dc magnetron reactive sputtering. For the anodic coloring material, Prussian blue nanoparticles (PBNPs) are synthesized and coated on the transparent Sn-doped indium oxide (ITO) glass. The thickness of ITO, WO3 and PB film is 110, 170 and 200 nm, respectively. The size of the ECD is 5×5 cm2. The effect of the introduction of SN into the GPEs is discussed by observing the electrochromic behaviors of the WO3-PB ECD. Besides, the composition ratio of PC to SN is also investigated by measuring the ionic conductivity. The optimized ratio of PC to SN is 4:1, and the ionic conductivity under this condition is 6.34x10-5 S∙cm-1, which is higher than that of PMMA/PC (1.35x10-6 S∙cm-1) and PMMA/EC/PC (4.52x10-6 S∙cm-1). This quasi-solid-state ECD fabricated with the PMMA/SN based GPE shows an optical contrast of ca. 53% at 690 nm. The optical transmittance of the ECD can be reversibly modulated from 72% (bleached) to 19% (darkened), by applying potentials of 1.5 and -2.2 V, respectively. During the durability test, the optical contrast of this ECD remains 44.5% after 2400 cycles, which is 83% of the original one.

Keywords: electrochromism, tungsten oxide, prussian blue, poly(methyl methacrylate), succinonitrile

Procedia PDF Downloads 280
2786 Geochemical Studies of Mud Volcanoes Fluids According to Petroleum Potential of the Lower Kura Depression (Azerbaijan)

Authors: Ayten Bakhtiyar Khasayeva

Abstract:

Lower Kura depression is a part of the South Caspian Basin (SCB), located between the folded regions of the Greater and Lesser Caucasus. The region is characterized by thick sedimentary cover 22 km (SCB up to 30 km), high sedimentation rate, low geothermal gradient (average value corresponds to 2 °C / 100m). There is Quaternary, Pliocene, Miocene and Oligocene deposits take part in geological structure. Miocene and Oligocene deposits are opened by prospecting and exploratory wells in the areas of Kalamaddin and Garabagli. There are 25 mud volcanoes within the territory of the Lower Kura depression, which are the unique source of information about hydrocarbons contenting great depths. During the wells data research, solid erupted products and mud volcano fluids, and according to the geological and thermal characteristics of the region, it was determined that the main phase of the hydrocarbon generation (MK1-AK2) corresponds to a wide range of depths from 10 to 14 km, which corresponds to the Pliocene-Miocene sediments, and to the "oil and gas windows" according to the intended meaning of R0 ≈ 0,65-0,85%. Fluids of mud volcanoes comprise by the following phases - gas, water. Gas phase consists mainly of methane (99%) of heavy hydrocarbons (С2+ hydrocarbons), CO2, N2, inert components He, Ar. The content of the С2+ hydrocarbons in the gases of mud volcanoes associated with oil deposits is increased. Carbon isotopic composition of methane for the Lower Kura depression varies from -40 ‰ to -60 ‰. Water of mud volcanoes are represented by all four genetic types. However the most typical types of water are HCN type. According to the Mg-Li geothermometer formation of mud waters corresponds to the temperature range from 20 °C to 140 °C (PC2). The solid product emissions of mud volcanoes identified 90 minerals and 30 trace elements. As a result geochemical investigation, thermobaric and geological conditions, zone oil and gas generation - the prospect of the Lower Kura depression is projected to depths greater than 10 km.

Keywords: geology, geochemistry, mud volcanoes, petroleum potential

Procedia PDF Downloads 349
2785 Assessment of Analytical Equations for the Derivation of Young’s Modulus of Bonded Rubber Materials

Authors: Z. N. Haji, S. O. Oyadiji, H. Samami, O. Farrell

Abstract:

The prediction of the vibration response of rubber products by analytical or numerical method depends mainly on the predefined intrinsic material properties such as Young’s modulus, damping factor and Poisson’s ratio. Such intrinsic properties are determined experimentally by subjecting a bonded rubber sample to compression tests. The compression tests on such a sample yield an apparent Young’s modulus which is greater in magnitude than the intrinsic Young’s modulus of the rubber. As a result, many analytical equations have been developed to determine Young’s modulus from an apparent Young’s modulus of bonded rubber materials. In this work, the applicability of some of these analytical equations is assessed via experimental testing. The assessment is based on testing of vulcanized nitrile butadiene rubber (NBR70) samples using tensile test and compression test methods. The analytical equations are used to determine the intrinsic Young’s modulus from the apparent modulus that is derived from the compression test data of the bonded rubber samples. Then, these Young’s moduli are compared with the actual Young’s modulus that is derived from the tensile test data. The results show significant discrepancy between the Young’s modulus derived using the analytical equations and the actual Young’s modulus.

Keywords: bonded rubber, quasi-static test, shape factor, apparent Young’s modulus

Procedia PDF Downloads 157
2784 Urban Logistics Dynamics: A User-Centric Approach to Traffic Modelling and Kinetic Parameter Analysis

Authors: Emilienne Lardy, Eric Ballot, Mariam Lafkihi

Abstract:

Efficient urban logistics requires a comprehensive understanding of traffic dynamics, particularly as it pertains to kinetic parameters influencing energy consumption and trip duration estimations. While real-time traffic information is increasingly accessible, current high-precision forecasting services embedded in route planning often function as opaque 'black boxes' for users. These services, typically relying on AI-processed counting data, fall short in accommodating open design parameters essential for management studies, notably within Supply Chain Management. This work revisits the modelling of traffic conditions in the context of city logistics, emphasizing its significance from the user’s point of view, with two focuses. Firstly, the focus is not on the vehicle flow but on the vehicles themselves and the impact of the traffic conditions on their driving behaviour. This means opening the range of studied indicators beyond vehicle speed, to describe extensively the kinetic and dynamic aspects of the driving behaviour. To achieve this, we leverage the Art. Kinema parameters are designed to characterize driving cycles. Secondly, this study examines how the driving context (i.e., exogenous factors to the traffic flow) determines the mentioned driving behaviour. Specifically, we explore how accurately the kinetic behaviour of a vehicle can be predicted based on a limited set of exogenous factors, such as time, day, road type, orientation, slope, and weather conditions. To answer this question, statistical analysis was conducted on real-world driving data, which includes high-frequency measurements of vehicle speed. A Factor Analysis and a Generalized Linear Model have been established to link kinetic parameters with independent categorical contextual variables. The results include an assessment of the adjustment quality and the robustness of the models, as well as an overview of the model’s outputs.

Keywords: factor analysis, generalised linear model, real world driving data, traffic congestion, urban logistics, vehicle kinematics

Procedia PDF Downloads 50
2783 Salinity Response of Some Chickpea (Cicer arietinum L.) Genotypes in Germination and Seedling Growth of Periods

Authors: Onder Aldemir, Ercan Ceyhan

Abstract:

The research was conducted to determine effects of salt concentrations on emergence and seedling development of chickpea genotypes. Trials were performed during the year of 2013 on the laboratory and greenhouse of Agricultural Faculty, Selcuk University. Emergency trial was set up according to ‘Randomized Plots Design’ by two factors and four replications; greenhouse trial was also set up according to ‘Randomized Plots Design’ by two factors with three replications. The chickpea genotypes; CA119, CA132, CA149, CA150, CA215, CA222, CA235, CA261, Bozkır and Gokce were used as material for both of the trials. Effects of the five doses of salt concentrations (control, 30 mM, 60 mM, 90 mM and 120 mM) on the ratio of emergency, speed of emergency, average time for emergency, index of sensibility, length of shoot and root, fresh weight of shoot and root, dry weight of shoot and root, index of salt tolerance were evaluated. Responses of the chickpea genotypes for salt concentrations were found different. Comparing to the control, all of the investigated characteristics on the chickpea genotypes showed significant reduction by depending on the increasing salt level. According to the effects of salt application, the chickpea genotypes Gokce, CA215 and CA222 were the most tolerant in respect to plant dry weights while the chickpea genotypes CA149 and CA150 were the most sensitive.

Keywords: chickpea, emergence, salt tolerant, seedling development

Procedia PDF Downloads 212
2782 Living Wall Systems: An Approach for Reducing Energy Consumption in Curtain Wall Façades

Authors: Salma Maher, Ahmed Elseragy, Sally Eldeeb

Abstract:

Nowadays, Urbanism and climate change lead to the rapid growth in energy consumption and the increase of using air-conditioning for cooling. In a hot climate area, there is a need for a new sustainable alternative that is more convenient for an existing situation. The Building envelope controls the heat transfer between the outside and inside the building. While the building façade is the most critical part, types of façade material play a vital role in influences of the energy demand for heating and cooling due to exposure to direct solar radiation throughout the day. Since the beginning of the twentieth century, the use of curtain walls in office buildings façades started to increase rapidly, which lead to more cooling loads in energy consumption. Integrating the living wall system in urban areas as a sustainable renovation and energy-saving method for the built environment will reduce the energy demand of buildings and will also provide environmental benefits. Also, it will balance the urban ecology and enhance urban life quality. The results show that the living wall systems reduce the internal temperature up to 4.0 °C. This research carries on an analytical study by highlighting the different types of living wall systems and verifying their thermal performance, energy-saving, and life potential on the building. These assessing criteria include the reason for using the Living wall systems in the building façade as well as the effect it has upon the surrounding environment. Finally, the paper ends with concluding the effect of using living wall systems on building. And, it suggests a system as long-lasting, and energy-efficient solution to be applied in curtain wall façades in a hot climate area.

Keywords: living wall systems, energy consumption, curtain walls, energy-saving, sustainability, urban life quality

Procedia PDF Downloads 128
2781 Inactivation of Rhodotorula spp. 74 with Cold Atmospheric Plasma

Authors: Zoran Herceg, Višnja Stulić, Tomislava Vukušić, Anet Režek Jambrak

Abstract:

High voltage electrical discharge is a new technology used for inactivation of pathogen microorganisms. Pathogen yeasts can cause diseases in humans if they are ingested. Nowadays new technologies have become the focus of researching all over the world. Rhodotorula is known as yeast that can cause diseases in humans. The aim of this study was to examine whether the high voltage electrical discharge treatment generated in gas phase has an influence on yeast reduction and recovery of Rhodotorula spp 74 in pure culture. Rhodotorula spp. 74 was treated in 200 mL of model solution. Treatment time (5 and 10 min), frequency (60 and 90 Hz) and injected gas (air or argon 99,99%) were changed. Titanium high voltage needle was used as high voltage electrode (positive polarity) through which air or argon was injected at the gas flow of 0.6 L/min. Experimental design and statistical analyses were obtained by Statgraphics Centurion software (StatPoint Technologies, Inc., VA, USA). The best inactivation rate 1.7 log10 reduction was observed after the 10 min of treatment, frequency of 90 Hz and injected air. Also with a longer treatment time inactivation rate was higher. After the 24 h recovery of treated samples was observed. Therefore the further optimization of method is needed to understand the mechanism of yeasts inactivation and cells recovery after the treatment. Acknowledgements: The authors would like to acknowledge the support by Croatian Science Foundation and research project ‘Application of electrical discharge plasma for preservation of liquid foods’.

Keywords: rhodotorula spp. 74, electrical discharge plasma, inactivation, stress response

Procedia PDF Downloads 222
2780 On the Effects of the Frequency and Amplitude of Sinusoidal External Cross-Flow Excitation Forces on the Vortex-Induced-Vibrations of an Oscillating Cylinder

Authors: Abouzar Kaboudian, Ravi Chaithanya Mysa, Boo Cheong Khoo, Rajeev Kumar Jaiman

Abstract:

Vortex induced vibrations can significantly affect the effectiveness of structures in aerospace as well as offshore marine industries. The oscillatory nature of the forces resulting from the vortex shedding around bluff bodies can result in undesirable effects such as increased loading, stresses, deflections, vibrations and noise in the structures, and also reduced fatigue life of the structures. To date, most studies concentrate on either the free oscillations or the prescribed motion of the bluff bodies. However, the structures in operation are usually subject to the external oscillatory forces (e.g. due to the platform motions in offshore industries). Periodic forces can be considered as a combinations of sinusoids. In this work, we present the effects of sinusoidal external cross-flow forces on the vortex-induced vibrations of an oscillating cylinder. The effects of the amplitude, as well as the frequency of these sinusoidal external force on the fluid-forces on the oscillating cylinder are carefully studied and presented. Moreover, we present the transition of the response to be dominated by the vortex-induced-vibrations to the range where it is mostly dictated by the external oscillatory forces. Furthermore, we will discuss how the external forces can affect the flow structures around a cylinder. All results are compared against free oscillations of the cylinder.

Keywords: circular cylinder, external force, vortex-shedding, VIV

Procedia PDF Downloads 355
2779 Evaluation of Possible Application of Cold Energy in Liquefied Natural Gas Complexes

Authors: А. I. Dovgyalo, S. O. Nekrasova, D. V. Sarmin, A. A. Shimanov, D. A. Uglanov

Abstract:

Usually liquefied natural gas (LNG) gasification is performed due to atmospheric heat. In order to produce a liquefied gas a sufficient amount of energy is to be consumed (about 1 kW∙h for 1 kg of LNG). This study offers a number of solutions, allowing using a cold energy of LNG. In this paper it is evaluated the application turbines installed behind the evaporator in LNG complex due to its work additional energy can be obtained and then converted into electricity. At the LNG consumption of G=1000kg/h the expansion work capacity of about 10 kW can be reached. Herewith-open Rankine cycle is realized, where a low capacity cryo-pump (about 500W) performs its normal function, providing the cycle pressure. Additionally discussed an application of Stirling engine within the LNG complex also gives a possibility to realize cold energy. Considering the fact, that efficiency coefficient of Stirling engine reaches 50 %, LNG consumption of G=1000 kg/h may result in getting a capacity of about 142 kW of such a thermal machine. The capacity of the pump, required to compensate pressure losses when LNG passes through the hydraulic channel, will make 500 W. Apart from the above-mentioned converters, it can be proposed to use thermoelectric generating packages (TGP), which are widely used now. At present, the modern thermoelectric generator line provides availability of electric capacity with coefficient of efficiency up to 15%. In the proposed complex, it is suggested to install the thermoelectric generator on the evaporator surface is such a way, that the cold end is contacted with the evaporator’s surface, and the hot one – with the atmosphere. At the LNG consumption of G=1000 kgг/h and specified coefficient of efficiency the capacity of the heat flow Qh will make about 32 kW. The derivable net electric power will be P=4,2 kW, and the number of packages will amount to about 104 pieces. The carried out calculations demonstrate the research perceptiveness in this field of propulsion plant development, as well as allow realizing the energy saving potential with the use of liquefied natural gas and other cryogenics technologies.

Keywords: cold energy, gasification, liquefied natural gas, electricity

Procedia PDF Downloads 262