Search results for: back calculation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2768

Search results for: back calculation

2558 Modular Data and Calculation Framework for a Technology-based Mapping of the Manufacturing Process According to the Value Stream Management Approach

Authors: Tim Wollert, Fabian Behrendt

Abstract:

Value Stream Management (VSM) is a widely used methodology in the context of Lean Management for improving end-to-end material and information flows from a supplier to a customer from a company’s perspective. Whereas the design principles, e.g. Pull, value-adding, customer-orientation and further ones are still valid against the background of an increasing digitalized and dynamic environment, the methodology itself for mapping a value stream is characterized as time- and resource-intensive due to the high degree of manual activities. The digitalization of processes in the context of Industry 4.0 enables new opportunities to reduce these manual efforts and make the VSM approach more agile. The paper at hand aims at providing a modular data and calculation framework, utilizing the available business data, provided by information and communication technologies for automizing the value stream mapping process with focus on the manufacturing process.

Keywords: lean management 4.0, value stream management (VSM) 4.0, dynamic value stream mapping, enterprise resource planning (ERP)

Procedia PDF Downloads 114
2557 Understanding Regional Circulations That Modulate Heavy Precipitations in the Kulfo Watershed

Authors: Tesfay Mekonnen Weldegerima

Abstract:

Analysis of precipitation time series is a fundamental undertaking in meteorology and hydrology. The extreme precipitation scenario of the Kulfo River watershed is studied using wavelet analysis and atmospheric transport, a lagrangian trajectory model. Daily rainfall data for the 1991-2020 study periods are collected from the office of the Ethiopian Meteorology Institute. Meteorological fields on a three-dimensional grid at 0.5o x 0.5o spatial resolution and daily temporal resolution are also obtained from the Global Data Assimilation System (GDAS). Wavelet analysis of the daily precipitation processed with the lag-1 coefficient reveals some high power recurred once every 38 to 60 days with greater than 95% confidence for red noise. The analysis also identified inter-annual periodicity in the periods 2002 - 2005 and 2017 - 2019. Back trajectory analysis for 3-day periods up to May 19/2011, indicates the Indian Ocean source; trajectories crossed the eastern African escarpment to arrive at the Kulfo watershed. Atmospheric flows associated with the Western Indian monsoon redirected by the low-level Somali winds and Arabian ridge are responsible for the moisture supply. The time-localization of the wavelet power spectrum yields valuable hydrological information, and the back trajectory approaches provide useful characterization of air mass source.

Keywords: extreme precipitation events, power spectrum, back trajectory, kulfo watershed

Procedia PDF Downloads 40
2556 Knee Pain Reduction: Holistic vs. Traditional

Authors: Renee Moten

Abstract:

Introduction: Knee pain becomes chronic because the therapy used focuses only on the symptoms of knee pain and not the causes of knee pain. Preventing knee injuries is not in the toolbox of the traditional practitioner. This research was done to show that we must reduce the inflammation (holistically), reduce the swelling and regain flexibility before considering any type of exercise. This method of performing the correct exercise stops the bowing of the knee, corrects the walking gait, and starts to relieve knee, hip, back, and shoulder pain. Method: The holistic method that is used to heal knees is called the Knee Pain Recipe. It’s a six step system that only uses alternative medicine methods to reduce, relieve and restore knee joint mobility. The system is low cost, with no hospital bills, no physical therapy, and no painkillers that can cause damage to the kidneys and liver. This method has been tested on 200 women with knee, back, hip, and shoulder pain. Results: All 200 women reduce their knee pain by 50%, some by as much as 90%. Learning about ankle and foot flexibility, along with understanding the kinetic chain, helps improve the walking gait, which takes the pressure off the knee, hip and back. The knee pain recipe also has helped to reduce the need for a cortisone injection, stem cell procedures, to take painkillers, and surgeries. What has also been noted in the research was that if the women's knees were too far gone, the Knee Pain Recipe helped prepare the women for knee replacement surgery. Conclusion: It is believed that the Knee Pain Recipe, when performed by men and women from around the world, will give them a holistic alternative to drugs, injections, and surgeries.

Keywords: knee, surgery, healing, holistic

Procedia PDF Downloads 46
2555 A Perspective of Digital Formation in the Solar Community as a Prototype for Finding Sustainable Algorithmic Conditions on Earth

Authors: Kunihisa Kakumoto

Abstract:

“Purpose”: Global environmental issues are now being raised in a global dimension. By predicting sprawl phenomena beyond the limits of nature with algorithms, we can expect to protect our social life within the limits of nature. It turns out that the sustainable state of the planet now consists in maintaining a balance between the capabilities of nature and the possibilities of our social life. The amount of water on earth is finite. Sustainability is therefore highly dependent on water capacity. A certain amount of water is stored in the forest by planting and green space, and the amount of water can be considered in relation to the green space. CO2 is also absorbed by green plants. "Possible measurements and methods": The concept of the solar community has been introduced in technical papers on the occasion of many international conferences. The solar community concept is based on data collected from one solar model house. This algorithmic study simulates the amount of water stored by lush green vegetation. In addition, we calculated and compared the amount of CO2 emissions from the Taiyo Community and the amount of CO2 reduction from greening. Based on the trial calculation results of these solar communities, we are simulating the sustainable state of the earth as an algorithm trial calculation result. We believe that we should also consider the composition of this solar community group using digital technology as control technology. "Conclusion": We consider the solar community as a prototype for finding sustainable conditions for the planet. The role of water is very important as the supply capacity of water is limited. However, the circulation of social life is not constructed according to the mechanism of nature. This simulation trial calculation is explained using the total water supply volume as an example. According to this process, algorithmic calculations consider the total capacity of the water supply and the population and habitable numbers of the area. Green vegetated land is very important to keep enough water. Green vegetation is also very important to maintain CO2 balance. A simulation trial calculation is possible from the relationship between the CO2 emissions of the solar community and the amount of CO2 reduction due to greening. In order to find this total balance and sustainable conditions, the algorithmic simulation calculation takes into account lush vegetation and total water supply. Research to find sustainable conditions is done by simulating an algorithmic model of the solar community as a prototype. In this one prototype example, it's balanced. The activities of our social life must take place within the permissive limits of natural mechanisms. Of course, we aim for a more ideal balance by utilizing auxiliary digital control technology such as AI.

Keywords: solar community, sustainability, prototype, algorithmic simulation

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2554 Camel Mortalities Due to Accidental Intoxcation with Ionophore

Authors: M. A. Abdelfattah, F. K. Waleed

Abstract:

Anticoccidials were utilized widely in veterinary practice for the avoidance of coccidiosis in poultry and assume a huge job as development promotants in ruminants. Ionophore harming is every now and again happens because of accidental access to medicated feed, errors in feed mixing, incorrect dosage calculation or misuse in non-recommended species. Camels on several farms in Eastern area of Saudi Arabia were accidently fed with a feed pellet containing 13 ppm salinomycin. One hundred and sixty-three camels died with mortality rate of 100%. The poisoning was clinically characterized by restlessness with tail lift to the top, jerk in the muscles of legs and thighs, excessive sweating, frequent setting and standing with body imbalance, lateral and sternal recumbences with the legs stretched back, eye tears with dilated pupil, vomiting of the stomach content, loss of consciousness and death of some of them. Feed analysis indicated the presence of salinomycin in pelleted feed in a range of 13 mg/kg-47 mg/kg. Necropsy findings and histopathological examinations were presented. Regulations and legal implications concerning with sale of contaminated feed in Saudi market are discussed in the light of feed law and by-law. The necessity for an effective implication of regulation concerning application of quality assurance systems based on the principles of Good Manufacturing Practice (GMP) and the application of Hazard Analysis of Critical Control Point (HACCP) during feed production is necessary to avoid feed accident.

Keywords: medicated feed, salinomycin, anticoccidial, camel, toxicity

Procedia PDF Downloads 84
2553 Calculation of Organs Radiation Dose in Cervical Carcinoma External Irradiation Beam Using Day’s Methods

Authors: Yousif M. Yousif Abdallah, Mohamed E. Gar-Elnabi, Abdoelrahman H. A. Bakary, Alaa M. H. Eltoum, Abdelazeem K. M. Ali

Abstract:

The study was established to measure the amount of radiation outside the treatment field in external beam radiation therapy using day method of dose calculation, the data was collected from 89 patients of cervical carcinoma in order to determine if the dose outside side the irradiation treatment field for spleen, liver, both kidneys, small bowel, large colon, skin within the acceptable limit or not. The cervical field included mainly 4 organs which are bladder, rectum part of small bowel and hip joint these organ received mean dose of (4781.987±281.321), (4736.91±331.8), (4647.64±387.1) and (4745.91±321.11) respectively. The mean dose received by outfield organs was (77.69±15.24cGy) to large colon, (93.079±12.31cGy) to right kidney (80.688±12.644cGy) to skin, (155.86±17.69cGy) to small bowel. This was more significant value noted.

Keywords: radiation dose, cervical carcinoma, day’s methods, radiation medicine

Procedia PDF Downloads 382
2552 Increasing of Gain in Unstable Thin Disk Resonator

Authors: M. Asl. Dehghan, M. H. Daemi, S. Radmard, S. H. Nabavi

Abstract:

Thin disk lasers are engineered for efficient thermal cooling and exhibit superior performance for this task. However the disk thickness and large pumped area make the use of this gain format in a resonator difficult when constructing a single-mode laser. Choosing an unstable resonator design is beneficial for this purpose. On the other hand, the low gain medium restricts the application of unstable resonators to low magnifications and therefore to a poor beam quality. A promising idea to enable the application of unstable resonators to wide aperture, low gain lasers is to couple a fraction of the out coupled radiation back into the resonator. The output coupling gets dependent on the ratio of the back reflection and can be adjusted independently from the magnification. The excitation of the converging wave can be done by the use of an external reflector. The resonator performance is numerically predicted. First of all the threshold condition of linear, V and 2V shape resonator is investigated. Results show that the maximum magnification is 1.066 that is very low for high quality purposes. Inserting an additional reflector covers the low gain. The reflectivity and the related magnification of a 350 micron Yb:YAG disk are calculated. The theoretical model was based on the coupled Kirchhoff integrals and solved numerically by the Fox and Li algorithm. Results show that with back reflection mechanism in combination with increasing the number of beam incidents on disk, high gain and high magnification can occur.

Keywords: unstable resonators, thin disk lasers, gain, external reflector

Procedia PDF Downloads 385
2551 Effect of Modeling of Hydraulic Form Loss Coefficient to Break on Emergency Core Coolant Bypass

Authors: Young S. Bang, Dong H. Yoon, Seung H. Yoo

Abstract:

Emergency Core Coolant Bypass (ECC Bypass) has been regarded as an important phenomenon to peak cladding temperature of large-break loss-of-coolant-accidents (LBLOCA) in nuclear power plants (NPP). A modeling scheme to address the ECC Bypass phenomena and the calculation of LBLOCA using that scheme are discussed in the present paper. A hydraulic form loss coefficient (HFLC) from the reactor vessel downcomer to the broken cold leg is predicted by the computational fluid dynamics (CFD) code with a variation of the void fraction incoming from the downcomer. The maximum, mean, and minimum values of FLC are derived from the CFD results and are incorporated into the LBLOCA calculation using a system thermal-hydraulic code, MARS-KS. As a relevant parameter addressing the ECC Bypass phenomena, the FLC to the break and its range are proposed.

Keywords: CFD analysis, ECC bypass, hydraulic form loss coefficient, system thermal-hydraulic code

Procedia PDF Downloads 200
2550 A Novel PWM/PFM Controller for PSR Fly-Back Converter Using a New Peak Sensing Technique

Authors: Sanguk Nam, Van Ha Nguyen, Hanjung Song

Abstract:

For low-power applications such as adapters for portable devices and USB chargers, the primary side regulation (PSR) fly-back converter is widely used in lieu of the conventional fly-back converter using opto-coupler because of its simpler structure and lower cost. In the literature, there has been studies focusing on the design of PSR circuit; however, the conventional sensing method in PSR circuit using RC delay has a lower accuracy as compared to the conventional fly-back converter using opto-coupler. In this paper, we propose a novel PWM/PFM controller using new sensing technique for the PSR fly-back converter which can control an accurate output voltage. The conventional PSR circuit can sense the output voltage information from the auxiliary winding to regulate the duty cycle of the clock that control the output voltage. In the sensing signal waveform, there has two transient points at time the voltage equals to Vout+VD and Vout, respectively. In other to sense the output voltage, the PSR circuit must detect the time at which the current of the diode at the output equals to zero. In the conventional PSR flyback-converter, the sensing signal at this time has a non-sharp-negative slope that might cause a difficulty in detecting the output voltage information since a delay of sensing signal or switching clock may exist which brings out an unstable operation of PSR fly-back converter. In this paper instead of detecting output voltage at a non-sharp-negative slope, a sharp-positive slope is used to sense the proper information of the output voltage. The proposed PRS circuit consists of a saw-tooth generator, a summing circuit, a sample and hold circuit and a peak detector. Besides, there is also the start-up circuit which protects the chip from high surge current when the converter is turned on. Additionally, to reduce the standby power loss, a second mode which operates in a low frequency is designed beside the main mode at high frequency. In general, the operation of the proposed PSR circuit can be summarized as following: At the time the output information is sensed from the auxiliary winding, a saw-tooth signal from the saw-tooth generator is generated. Then, both of these signals are summed using a summing circuit. After this process, the slope of the peak of the sensing signal at the time diode current is zero becomes positive and sharp that make the peak easy to detect. The output of the summing circuit then is fed into a peak detector and the sample and hold circuit; hence, the output voltage can be properly sensed. By this way, we can sense more accurate output voltage information and extend margin even circuit is delayed or even there is the existence of noise by using only a simple circuit structure as compared with conventional circuits while the performance can be sufficiently enhanced. Circuit verification was carried out using 0.35μm 700V Magnachip process. The simulation result of sensing signal shows a maximum error of 5mV under various load and line conditions which means the operation of the converter is stable. As compared to the conventional circuit, we achieved very small error only used analog circuits compare with conventional circuits. In this paper, a PWM/PFM controller using a simple and effective sensing method for PSR fly-back converter has been presented in this paper. The circuit structure is simple as compared with the conventional designs. The gained results from simulation confirmed the idea of the design

Keywords: primary side regulation, PSR, sensing technique, peak detector, PWM/PFM control, fly-back converter

Procedia PDF Downloads 315
2549 High-Pressure Calculations of the Elastic Properties of ZnSx Se 1−x Alloy in the Virtual-Crystal Approximation

Authors: N. Lebga, Kh. Bouamama, K. Kassali

Abstract:

We report first-principles calculation results on the structural and elastic properties of ZnS x Se1−x alloy for which we employed the virtual crystal approximation provided with the ABINIT program. The calculations done using density functional theory within the local density approximation and employing the virtual-crystal approximation, we made a comparative study between the numerical results obtained from ab-initio calculation using ABINIT or Wien2k within the Density Functional Theory framework with either Local Density Approximation or Generalized Gradient approximation and the pseudo-potential plane-wave method with the Hartwigzen Goedecker Hutter scheme potentials. It is found that the lattice parameter, the phase transition pressure, and the elastic constants (and their derivative with respect to the pressure) follow a quadratic law in x. The variation of the elastic constants is also numerically studied and the phase transformations are discussed in relation to the mechanical stability criteria.

Keywords: density functional theory, elastic properties, ZnS, ZnSe,

Procedia PDF Downloads 546
2548 Translation and Adaptation of the Assessment Instrument “Kiddycat” for European Portuguese

Authors: Elsa Marta Soares, Ana Rita Valente, Cristiana Rodrigues, Filipa Gonçalves

Abstract:

Background: The assessment of feelings and attitudes of preschool children in relation to stuttering is crucial. Negative experiences can lead to anxiety, worry or frustration. To avoid the worsening of attitudes and feelings related to stuttering, it is important the early detection in order to intervene as soon as possible through an individualized intervention plan. Then it is important to have Portuguese instruments that allow this assessment. Aims: The aim of the present study is to realize the translation and adaptation of the Communication Attitude Test for Children in Preschool Age and Kindergarten (KiddyCat) for EP. Methodology: For the translation and adaptation process, a methodological study was carried out with the following steps: translation, back translation, assessment by a committee of experts and pre-test. This abstract describes the results of the first two phases of this process. The translation was accomplished by two bilingual individuals without experience in health and any knowledge about the instrument. One of them was an English teacher and the other one a Translator. The back-translation was conducted by two Senior Class Teachers that live in United Kingdom without any knowledge in health and about the instrument. Results and Discussion: In translation there were differences in semantic equivalences of various expressions and concepts. A discussion between the two translators, mediated by the researchers, allowed to achieve the consensus version of the translated instrument. Taking into account the original version of KiddyCAT the results demonstrated that back-translation versions were similar to the original version of this assessment instrument. Although the back-translators used different words, they were synonymous, maintaining semantic and idiomatic equivalences of the instrument’s items. Conclusion: This project contributes with an important resource that can be used in the assessment of feelings and attitudes of preschool children who stutter. This was the first phase of the research; expert panel and pretest are being developed. Therefore, it is expected that this instrument contributes to an holistic therapeutic intervention, taking into account the individual characteristics of each child.

Keywords: assessment, feelings and attitudes, preschool children, stuttering

Procedia PDF Downloads 125
2547 Improving Radiation Efficiency Using Metamaterial in Pyramidal Horn Antenna

Authors: Amit Kumar Baghel, Sisir Kumar Nayak

Abstract:

The proposed metamaterial design help to increase the radiation efficiency at 2.9 GHz by reducing the side and back lobes by making the phase difference of the waves emerging from the phase center of the horn antenna same after passing through metamaterial array. The unit cell of the metamaterial is having concentric ring structure made of copper of 0.035 mm thickness on both sides of FR4 sheet. The inner ring diameter is kept as 3 mm, and the outer ring diameters are changed according to the path and tramission phase difference of the unit cell from the phase center of the antenna in both the horizontal and vertical direction, i.e., in x- and y-axis. In this case, the ring radius varies from 3.19 mm to 6.99 mm with the respective S21 phase difference of -62.25° to -124.64°. The total phase difference can be calculated by adding the path difference of the respective unit cell in the array to the phase difference of S21. Taking one of the unit cell as the reference, the total phase difference between the reference unit cell and other cells must be integer multiple of 360°. The variation of transmission coefficient S21 with the ring radius is greater than -6 dB. The array having 5 x 5 unit cell is kept inside the pyramidal horn antenna (L X B X H = 295.451 x 384.233 x 298.66 mm3) at a distance of 36.68 mm from the waveguide throat. There is an improvement in side lobe level in E-plane by 14.6 dB when the array is used. The front to back lobe ration is increased by 1 dB by using the array. The proposed antenna with metamaterial array can be used in beam shaping for wireless power transfer applications.

Keywords: metamaterial, side lobe level, front to back ratio, beam forming

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2546 Raman and FTIR Studies of Azobenzene: Experimental and Theoretical Approach

Authors: Gomti Devi

Abstract:

Photoisomerization has been attracting to researchers due to its wide range of applications in optical switches, polymeric chains, liquid-crystalline systems and bilayer membranes etc. Azobenzene is a photochromic molecule which exhibits a reversible isomerisation process between its trans and cis isomers of different stability. An investigation has been conducted of the effects of temperature on intensity and position of Raman band of N=N, C-N stretching modes of Azobenzene (AZBN). It was found that the N=N stretching mode of Raman band shape shifts to lower frequency region with the increase in temperature. The Raman intensity was also decreased with the increase of temperature. The change in bandwidth with the increase in temperature has been studied. The FTIR spectrum of the molecule is recorded so as to complement the Raman spectra. In order to investigate the possibility of undergoing dimerization and trimerization as well as the stability of this molecule, ab initio calculation for geometry optimization and vibrational wavenumber calculation have been performed. Theoretically calculated values are found in good agreement with the experimental results.

Keywords: azobenzene, temperature, ab-initio, frequency

Procedia PDF Downloads 312
2545 A Deep Learning Approach to Calculate Cardiothoracic Ratio From Chest Radiographs

Authors: Pranav Ajmera, Amit Kharat, Tanveer Gupte, Richa Pant, Viraj Kulkarni, Vinay Duddalwar, Purnachandra Lamghare

Abstract:

The cardiothoracic ratio (CTR) is the ratio of the diameter of the heart to the diameter of the thorax. An abnormal CTR, that is, a value greater than 0.55, is often an indicator of an underlying pathological condition. The accurate prediction of an abnormal CTR from chest X-rays (CXRs) aids in the early diagnosis of clinical conditions. We propose a deep learning-based model for automatic CTR calculation that can assist the radiologist with the diagnosis of cardiomegaly and optimize the radiology flow. The study population included 1012 posteroanterior (PA) CXRs from a single institution. The Attention U-Net deep learning (DL) architecture was used for the automatic calculation of CTR. A CTR of 0.55 was used as a cut-off to categorize the condition as cardiomegaly present or absent. An observer performance test was conducted to assess the radiologist's performance in diagnosing cardiomegaly with and without artificial intelligence (AI) assistance. The Attention U-Net model was highly specific in calculating the CTR. The model exhibited a sensitivity of 0.80 [95% CI: 0.75, 0.85], precision of 0.99 [95% CI: 0.98, 1], and a F1 score of 0.88 [95% CI: 0.85, 0.91]. During the analysis, we observed that 51 out of 1012 samples were misclassified by the model when compared to annotations made by the expert radiologist. We further observed that the sensitivity of the reviewing radiologist in identifying cardiomegaly increased from 40.50% to 88.4% when aided by the AI-generated CTR. Our segmentation-based AI model demonstrated high specificity and sensitivity for CTR calculation. The performance of the radiologist on the observer performance test improved significantly with AI assistance. A DL-based segmentation model for rapid quantification of CTR can therefore have significant potential to be used in clinical workflows.

Keywords: cardiomegaly, deep learning, chest radiograph, artificial intelligence, cardiothoracic ratio

Procedia PDF Downloads 66
2544 Astronmical Panels of Measuring and Dividing Time in Ancient Egypt

Authors: Laila Mahrous Moursy Moawad El-Habiby

Abstract:

The ancient Egyptian used the stars to measure time or in a more precise sense as one of the astronomical means of measuring time. These methods differed throughout the historical ages. They began with simple observations of observing astronomical phenomena and watching them, such as observing the movements of the stars in the sky. The year, to know the days, nights, and other means used to help set the time when the sky overcast, and so the researcher tries through archaeological evidence to demonstrate the knowledge of the ancient Egyptian stars of heaven, and movements through the first pre-history. It is not believed that the astronomical information possessed by the Egyptian was limited, and simple, it was reaching a level of almost optimal in terms of importance, and the goal he wanted to reach the ancient Egyptian, and also help him to know the time, and the passage of time; which ended in finally trying to find a system of timing and calculation of time. It was noted that there were signs that the stellar creed was known, and prosperous, especially since the pre-family ages, and this is evident on the inscriptions that come back to that period. The Egyptian realized that some of the stars remain visible at night, The ancient Egyptian was familiar with the daily journey of the stars. This is what was adopted in many paragraphs of the texts of the pyramids, and its references to the rise of the deceased king of the heavenly world between the stars of the eternal sky. It was noted that the ancient Egyptian link between the doctrine of the star, we find that the public The lunar was known to the ancient Egyptian, and sang it for two years: and the stellar solar; but it was based on the appearance of the star Sirius, and this is the first means used to measure time, and know the calendar stars.

Keywords: archaeology, ancient Egypt, ancient Egyptian, astronomical panels

Procedia PDF Downloads 54
2543 TiN/TiO2 Nanostructure Coating on Glass Substrate

Authors: F. Dabir, R. Sarraf-Mamoory, N. Riahi-Noori

Abstract:

In this work, a nanostructured TiO2 layer was coated onto a FTO-less glass substrate using screen printing technique for back contact DSSC application. Then, titanium nitride thin film was applied on TiO2 layer by plasma assisted chemical vapor deposition (PACVD) as charge collector layer. The microstructure of prepared TiO2 layer was characterized by SEM. The sheet resistance, microstructure and elemental composition of titanium nitride thin films were analysed by four point probe, SEM, and EDS, respectively. TiO2 layer had porous nanostructure. The EDS analysis of TiN thin film showed presence of chlorine impurity. Sheet resistance of TiN thin film was 30 Ω/sq. With respect to the results, PACVD TiN can be a good candidate as a charge collector layer in back contacts DSSC.

Keywords: TiO2, TiN, charge collector, DSSC

Procedia PDF Downloads 441
2542 Identification of Workplace Hazards of Underground Coal Mines

Authors: Madiha Ijaz, Muhammad Akram, Sima Mir

Abstract:

Underground mining of coal is carried out manually in Pakistan. Exposure to ergonomic hazards (musculoskeletal disorders) are very common among the coal cutters of these mines. Cutting coal in narrow spaces poses a great threat to both upper and lower limbs of these workers. To observe the prevalence of such hazards, a thorough study was conducted on 600 workers from 30 mines (20 workers from 1 mine), located in two districts of province Punjab, Pakistan. Rapid Upper Limb Assessment sheet and Rapid Entire Body Assessment sheet were used for the study along with a standard Nordic Musculoskeleton disorder questionnaire. SPSS, 25, software was used for data analysis on upper and lower limb disorders, and regression analysis models were run for upper and lower back pain. According to the results obtained, it was found that work stages (drilling & blasting, coal cutting, timbering & supporting, etc.), wok experience and number of repetitions performed/minute were significant (with p-value 0.00,0.004 and 0.009, respectively) for discomfort in upper and lower limb. Age got p vale 0.00 for upper limb and 0.012 for lower limb disorder. The task of coal cutting was strongly associated with the pain in upper back (with odd ratios13.21, 95% confidence interval (CI)14.0-21.64)) and lower back pain (3.7, 95% confidence interval 1.3-4.2). scored on RULA and REBA sheets, every work-stage was ranked at 7-highest level of risk involved. Workers were young (mean value of age= 28.7 years) with mean BMI 28.1 kg/m2

Keywords: workplace hazards, ergonomic disorders, limb disorders, MSDs.

Procedia PDF Downloads 56
2541 Astronmical Panels of Measuring and Dividing Time in Ancient Egypt

Authors: Haitham Nabil Zaghlol Hasan

Abstract:

The ancient Egyptian used the stars to measure time or, in a more precise sense, as one of the astronomical means of measuring time. These methods differed throughout the historical ages. They began with simple observations of observing astronomical phenomena and watching them, such as observing the movements of the stars in the sky. The year, to know the days, nights, and other means used to help set the time when the sky overcast, and so the researcher tries through archaeological evidence to demonstrate the knowledge of the ancient Egyptian stars of heaven and movements through the first pre-history. It is not believed that the astronomical information possessed by the Egyptian was limited and simple, it was reaching a level of almost optimal in terms of importance, and the goal he wanted to reach the ancient Egyptian and also help him to know the time, and the passage of time; which ended in finally trying to find a system of timing and calculation of time. It was noted that there were signs that the stellar creed was known and prosperous, especially since the pre-family ages, and this is evident on the inscriptions that come back to that period. The Egyptian realized that some of the stars remain visible at night, The ancient Egyptian was familiar with the daily journey of the stars. This is what was adopted in many paragraphs of the texts of the pyramids and its references to the rise of the deceased king of the heavenly world between the stars of the eternal sky. It was noted that the ancient Egyptian link between the doctrine of the star, we find that the public The lunar was known to the ancient Egyptian, and sang it for two years: and the stellar solar; but it was based on the appearance of the star Sirius, and this is the first means used to measure time and know the calendar stars.

Keywords: ancient Egypt, astronmical panels, archaeology, civilization

Procedia PDF Downloads 48
2540 Enhancements to the Coupled Hydro-Mechanical Hypoplastic Model for Unsaturated Soils

Authors: Shanujah Mathuranayagam, William Fuentes, Samanthika Liyanapathirana

Abstract:

This paper introduces an enhanced version of the coupled hydro-mechanical hypoplastic model. The model is able to simulate volumetric collapse upon wetting and incorporates suction effects on stiffness and strength. Its mechanical constitutive equation links Bishop’s effective stress with strain and suction, featuring a normal consolidation line (NCL) with a compression index (λ) presenting a non-linear dependency with the degree of saturation. The Bulk modulus has been modified to ensure that under rapid volumetric collapse, the stress state remains at the NCL. The coupled model comprises eighteen parameters, with nine for the hydraulic component and nine for the mechanical component. Hydraulic parameters are calibrated with the use of water retention curves (IWRC) across varied soil densities, while mechanical parameters undergo calibration using isotropic and triaxial tests on both unsaturated and saturated samples. The model's performance is analyzed through the back-calculation of two experimental studies: (i) wetting under different vertical stresses for Lower Cromer Till and (ii) isotropic loading and triaxial loading for undisturbed loess. The results confirm that the proposed model is able to predict the hydro-mechanical behavior of unsaturated soils.

Keywords: hypoplastic model, volumetric collapse, normal consolidation line, compression index (λ), degree of saturation, soil suction

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2539 Analytical Modeling of Equivalent Magnetic Circuit in Multi-segment and Multi-barrier Synchronous Reluctance Motor

Authors: Huai-Cong Liu,Tae Chul Jeong,Ju Lee

Abstract:

This paper describes characteristic analysis of a synchronous reluctance motor (SynRM)’s rotor with the Multi-segment and Multi-layer structure. The magnetic-saturation phenomenon in SynRM is often appeared. Therefore, when modeling analysis of SynRM the calculation of nonlinear magnetic field needs to be considered. An important influence factor on the convergence process is how to determine the relative permeability. An improved method, which ensures the calculation, is convergence by linear iterative method for saturated magnetic field. If there are inflection points on the magnetic curve,an optimum convergence method of solution for nonlinear magnetic field was provided. Then the equivalent magnetic circuit is calculated, and d,q-axis inductance can be got. At last, this process is applied to design a 7.5Kw SynRM and its validity is verified by comparing with the result of finite element method (FEM) and experimental test data.

Keywords: SynRM, magnetic-saturation, magnetic circuit, analytical modeling

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2538 Astronomical Panels of Measuring and Dividing Time in Ancient Egypt

Authors: Mohamed Saeed Ahmed Salman

Abstract:

The ancient Egyptians used the stars to measure time or, in a more precise sense, as one of the astronomical means of measuring time. These methods differed throughout the historical ages. They began with simple observations of observing astronomical phenomena and watching them, such as observing the movements of the stars in the sky. The year, to know the days, nights, and other means used to help set the time when the sky overcast, and so the researcher tries through archaeological evidence to demonstrate the knowledge of the ancient Egyptian stars of heaven and movements through the first pre-history. It is not believed that the astronomical information possessed by the Egyptians was limited, and simply, it was reaching a level of almost optimal in terms of importance, and the goal he wanted to reach the ancient Egyptians and also help him to know the time, and the passage of time; which ended in finally trying to find a system of timing and calculation of time. It was noted that there were signs that the stellar creed was known and prosperous, especially since the pre-family ages, and this is evident in the inscriptions that come back to that period. The Egyptians realized that some of the stars remained visible at night; the ancient Egyptians were familiar with the daily journey of the stars. This is what was adopted in many paragraphs of the texts of the pyramids and its references to the rise of the deceased king of the heavenly world between the stars of the eternal sky. It was noted that the ancient Egyptian link between the doctrine of the star, we find that the public The lunar was known to the ancient Egyptians, and sang it for two years, and the stellar solar; but it was based on the appearance of the star Sirius, and this is the first means used to measure time and know the calendar stars.

Keywords: archaeology, Astronmical panels, ancient Egypt, ancient Egyptian

Procedia PDF Downloads 26
2537 Validation of Codes Dragon4 and Donjon4 by Calculating Keff of a Slowpoke-2 Reactor

Authors: Otman Jai, Otman Elhajjaji, Jaouad Tajmouati

Abstract:

Several neutronic calculation codes must be used to solve the equation for different levels of discretization which all necessitate a specific modelisation. This chain of such models, known as a calculation scheme, leads to the knowledge of the neutron flux in a reactor from its own geometry, its isotopic compositions and a cross-section library. Being small in size, the 'Slowpoke-2' reactor is difficult to model due to the importance of the leaking neutrons. In the paper, the simulation model is presented (geometry, cross section library, assumption, etc.), and the results obtained by DRAGON4/DONJON4 codes were compared to the calculations performed with Monte Carlo code MCNP using detailed geometrical model of the reactor and the experimental data. Criticality calculations have been performed to verify and validate the model. Since created model properly describes the reactor core, it can be used for calculations of reactor core parameters and for optimization of research reactor application.

Keywords: transport equation, Dragon4, Donjon4, neutron flux, effective multiplication factor

Procedia PDF Downloads 444
2536 Investigation on Mesh Sensitivity of a Transient Model for Nozzle Clogging

Authors: H. Barati, M. Wu, A. Kharicha, A. Ludwig

Abstract:

A transient model for nozzle clogging has been developed and successfully validated against a laboratory experiment. Key steps of clogging are considered: transport of particles by turbulent flow towards the nozzle wall; interactions between fluid flow and nozzle wall, and the adhesion of the particle on the wall; the growth of the clog layer and its interaction with the flow. The current paper is to investigate the mesh (size and type) sensitivity of the model in both two and three dimensions. It is found that the algorithm for clog growth alone excluding the flow effect is insensitive to the mesh type and size, but the calculation including flow becomes sensitive to the mesh quality. The use of 2D meshes leads to overestimation of the clog growth because the 3D nature of flow in the boundary layer cannot be properly solved by 2D calculation. 3D simulation with tetrahedron mesh can also lead to an error estimation of the clog growth. A mesh-independent result can be achieved with hexahedral mesh, or at least with triangular prism (inflation layer) for near-wall regions.

Keywords: clogging, continuous casting, inclusion, simulation, submerged entry nozzle

Procedia PDF Downloads 256
2535 Partially-Averaged Navier-Stokes for Computations of Flow Around Three-Dimensional Ahmed Bodies

Authors: Maryam Mirzaei, Sinisa Krajnovic´

Abstract:

The paper reports a study about the prediction of flows around simplified vehicles using Partially-Averaged Navier-Stokes (PANS). Numerical simulations are performed for two simplified vehicles: A slanted-back Ahmed body at Re=30 000 and a square back Ahmed body at Re=300 000. A comparison of the resolved and modeled physical flow scales is made with corresponding LES and experimental data for a better understanding of the performance of the PANS model. The PANS model is compared for coarse and fine grid resolutions and it is indicated that even a coarse-grid PANS simulation is able to produce fairly close flow predictions to those from a well-resolved LES simulation. The results indicate the possibility of improvement of the predictions by employing a finer grid resolution.

Keywords: partially-averaged Navier-Stokes, large eddy simulation, PANS, LES, Ahmed body

Procedia PDF Downloads 559
2534 DFT Study of Half Sandwich of Vanadium (IV) Cyclopentadienyl Complexes

Authors: Salem El-Tohami Ashoor

Abstract:

A novel new vanadium (IV) complexes incorporating the chelating diamido cyclopentadienyl {ArN(CH2)3NAr)}2-((ηn-Cp)Cp)} (Ar = 2,6-Pri2C6H3)(Cp = C5H5 and n = 1,2,3,4 and 5) have been studied with calculation of the properties of species involved in various of cyclopentadienyl reaction. These were carried out under investigation of density functional theory (DFT) calculation, and comparing together. Other methods, explicitly including electron correlation, are necessary for more accurate calculations; MB3LYP (Becke) (Lee–Yang–Parr) level of theory often being used to obtain more exact results. These complexes were estimated of electronic energy for molecular system, because it accounts for all electron correlation interactions. The optimised of [V(ArN(CH2)3NAr)2Cl(η5-Cp)] (Ar = 2,6-Pri2C6H3 and Cp= C5H5) was found to be thermally more stable than others of vanadium cyclopentadienyl. In the meantime the complex [V(ArN(CH2)3NAr)2Cl(η1-Cp)] (Ar = 2,6-Pri2C6H3 and Cp= C5H5) which is showed a low thermal stability in case of the just one carbon of cyclopentadienyl can be insertion with vanadium metal centre. By using Dewar-Chatt-Duncanson model, as a basis of the molecular orbital (MO) analysis and showed the highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital LUMO.

Keywords: vanadium (IV) cyclopentadienyl complexes, DFT, MO, HOMO, LUMO

Procedia PDF Downloads 389
2533 Mathematical Modeling for Diabetes Prediction: A Neuro-Fuzzy Approach

Authors: Vijay Kr. Yadav, Nilam Rathi

Abstract:

Accurate prediction of glucose level for diabetes mellitus is required to avoid affecting the functioning of major organs of human body. This study describes the fundamental assumptions and two different methodologies of the Blood glucose prediction. First is based on the back-propagation algorithm of Artificial Neural Network (ANN), and second is based on the Neuro-Fuzzy technique, called Fuzzy Inference System (FIS). Errors between proposed methods further discussed through various statistical methods such as mean square error (MSE), normalised mean absolute error (NMAE). The main objective of present study is to develop mathematical model for blood glucose prediction before 12 hours advanced using data set of three patients for 60 days. The comparative studies of the accuracy with other existing models are also made with same data set.

Keywords: back-propagation, diabetes mellitus, fuzzy inference system, neuro-fuzzy

Procedia PDF Downloads 227
2532 Design of Demand Pacemaker Using an Embedded Controller

Authors: C. Bala Prashanth Reddy, B. Abhinay, C. Sreekar, D. V. Shobhana Priscilla

Abstract:

The project aims in designing an emergency pacemaker which is capable of giving shocks to a human heart which has stopped working suddenly. A pacemaker is a machine commonly used by cardiologists. This machine is used in order to shock a human’s heart back into usage. The way the heart works is that there are small cells called pacemakers sending electrical pulses to cardiac muscles that tell the heart when to pump blood. When these electrical pulses stop, the heart stops beating. When this happens, a pacemaker is used to shock the heart muscles and the pacemakers back into action. The way this is achieved is by rubbing the two panels of the pacemaker together to create an adequate electrical current, and then the heart gets back to the normal state. The project aims in designing a system which is capable of continuously displaying the heart beat and blood pressure of a person on LCD. The concerned doctor gets the heart beat and also the blood pressure details continuously through the GSM Modem in the form of SMS alerts. In case of abnormal condition, the doctor sends message format regarding the amount of electric shock needed. Automatically the microcontroller gives the input to the pacemaker which in turn gives the shock to the patient. Heart beat monitor and display system is a portable and a best replacement for the old model stethoscope which is less efficient. The heart beat rate is calculated manually using stethoscope where the probability of error is high because the heart beat rate lies in the range of 70 to 90 per minute whose occurrence is less than 1 sec, so this device can be considered as a very good alternative instead of a stethoscope.

Keywords: missing R wave, PWM, demand pacemaker, heart

Procedia PDF Downloads 443
2531 Designing an Intelligent Voltage Instability System in Power Distribution Systems in the Philippines Using IEEE 14 Bus Test System

Authors: Pocholo Rodriguez, Anne Bernadine Ocampo, Ian Benedict Chan, Janric Micah Gray

Abstract:

The state of an electric power system may be classified as either stable or unstable. The borderline of stability is at any condition for which a slight change in an unfavourable direction of any pertinent quantity will cause instability. Voltage instability in power distribution systems could lead to voltage collapse and thus power blackouts. The researchers will present an intelligent system using back propagation algorithm that can detect voltage instability and output voltage of a power distribution and classify it as stable or unstable. The researchers’ work is the use of parameters involved in voltage instability as input parameters to the neural network for training and testing purposes that can provide faster detection and monitoring of the power distribution system.

Keywords: back-propagation algorithm, load instability, neural network, power distribution system

Procedia PDF Downloads 404
2530 Prevalence and Risk Factors of Low Back Disorder among Waste Collection Workers: A Systematic Review

Authors: Benedicta Asante, Catherine Trask, Brenna Bath

Abstract:

Background: Waste Collection Workers’ (WCWs) activities contribute greatly to the recycling sector and are an important component of the waste management industry. As the recycling sector evolves, there is the increase in reports of injuries, particularly for common and debilitating musculoskeletal disorders such as low back disorder (LBD). WCWs are likely exposed to diverse work-related hazards that could contribute to LBD. However, there is currently no summary of the state of knowledge on the prevalence and risk factors of LBD within this workforce. Method: A comprehensive search was conducted in Ovid Medline, EMBASE, and Global Health e-publications with search term categories ‘low back disorder’ and ‘waste collection workers’. Two reviewers screened articles at title, abstract, and full-text stages. Data were extracted on study design, sampling strategy, socio-demographics, geographical region, and exposure definition, the definition of LBD, response rate, statistical techniques, LBD prevalence and risk factors. The risk of bias was assessed with a standardized tool. Results: The search of three databases generated 79 studies. Thirty-two studies met the study inclusion criteria for both title and abstract; only thirteen full-text articles met the study criteria and underwent data extraction. The majority of articles reported a 12-month prevalence of LBD between 16-74%. Although none of the included studies quantified relationships between risk factors and LBD, the suggested risk factors for LBD among WCWs included: awkward posture; lifting; pulling; pushing; repetitive motions; work duration; and physical loads. Conclusion: LBD is a major occupational health issue among WCWs. In light of these risks and future growth in this industry, further research should focus on the investigation of risk factors, with more focus on ergonomic exposure assessment, and LBD prevention efforts.

Keywords: low back pain, scavenger, waste pickers, waste collection workers

Procedia PDF Downloads 226
2529 Astronomical Panels of Measuring and Dividing Time in Egyptian Civilization

Authors: Hazem Taha Abouelnaga Ali, Mohamed Ahmed Madkour, Haitham Magdy Hamad

Abstract:

The ancient Egyptian used the stars to measure time or, in a more precise sense, as one of the astronomical means of measuring time. These methods differed throughout the historical ages. They began with simple observations of observing astronomical phenomena and watching them, such as observing the movements of the stars in the sky. The year, to know the days, nights, and other means used to help set the time when the sky overcast, and so the researcher tries through archaeological evidence to demonstrate the knowledge of the ancient Egyptian stars of heaven and movements through the first pre-history. It is not believed that the astronomical information possessed by the Egyptian was limited, and simple, it was reaching a level of almost optimal in terms of importance, and the goal he wanted to reach the ancient Egyptian and also help him to know the time, and the passage of time; which ended in finally trying to find a system of timing and calculation of time. It was noted that there were signs that the stellar creed was known and prosperous, especially since the pre-family ages, and this is evident on the inscriptions that come back to that period. The Egyptian realized that some of the stars remain visible at night, The ancient Egyptian was familiar with the daily journey of the stars. This is what was adopted in many paragraphs of the texts of the pyramids and its references to the rise of the deceased king of the heavenly world between the stars of the eternal sky. It was noted that the ancient Egyptian link between the doctrine of the star, we find that the public The lunar was known to the ancient Egyptian, and sang it for two years: and the stellar solar; but it was based on the appearance of the star Sirius, and this is the first means used to measure time and know the calendar stars.

Keywords: ancient egypt, archaeology, egyptian history, egyptian civilization, civilization

Procedia PDF Downloads 38