Search results for: numerical rating score

Authors: Nicola Milani, Carla Bellissimo, Davide Pogliana, Davide Panzin, Luca Garlaschelli, Giulia Facchinetti, Claudia Casson, Luca Marazzina, Andrea Sartori, Simone Rivaroli, Jeff Konin

Abstract:

The patient is a 26 year-old male amateur football player from Milan, Italy; (81kg; 185cm; BMI 23.6 kg/m²). He sustained a non-contact anterior cruciate ligament tear to his right knee in June 2021. In September 2021, his right knee ligament was reconstructed using a semitendinosus graft. The injury occurred during a football match on natural grass with typical shoes on a warm day (32 degrees celsius). Playing as a defender he sustained the injury during a change of direction, where the foot was fixated on the grass. He felt pain and was unable to continue playing the match. The surgeon approved his rehabilitation to begin two weeks post-operative. The initial physiotherapist assessment determined performing two training sessions per day within the first three months. In the first three weeks, the pain was 4/10 on Numerical Rating Scale (NRS), no swelling, a range of motion was 0-110°, with difficulty fully extending his knee and minimal quadriceps activation. Crutches were discontinued at four weeks with improved walking. Active exercise, electrostimulator, physical therapy, massages, osteopathy, and passive motion were initiated. At week 6, he completed his first functional movement screen; the score was 16/21 with no pain and no swelling. At week 8, the isokinetic test showed a 23% differential deficit between the two legs in maximum strength (at 90°/s). At week 10, he improved to 15% of injury-induced deficit which suggested he was ready to start running. At week 12, the athlete sustained his first threshold test. At week 16, he performed his first return to sports movement assessment, which revealed a 10% stronger difference between the legs. At week 16, he had his second threshold test. At week 17, his first on-field test revealed a 5% differential deficit between the two legs in the hop test. At week 18, isokinetic test demonstrates that the uninjured leg was 7% stronger than the recovering leg in maximum strength (at 90°/s). At week 20, his second on-field test revealed a 2% difference in hop test; at week 21, his third isokinetic test demonstrated a difference of 5% in maximum strength (at 90°/s). At week 21, he performed his second return to sports movement assessment which revealed a 2% difference between the limbs. Since it was the end of the championship, the team asked him to partake in the playoffs; moreover the player was very motivated to participate in the playoffs also because he was the captain of the team. Together with the player and the team, we decided to let him play even though we were aware of a heightened risk of injury than what is reported in the literature because of two factors: biological recovery times and the results of the tests we performed. In the decision making process about the athlete’s recovery time, it is important to balance the information available from the literature with the desires of the patient to avoid frustration.

Keywords: ACL, football, rehabilitation, return to play

Procedia PDF Downloads 117

Authors: Louis N. Y. Wong

Abstract:

En-echelon fractures are commonly found in rocks, which appear as a special set of regularly oriented and spaced fractures. By using both experimental and numerical approaches, this study investigates the interaction among them, and how this interaction finally contributes to the development of a shear rupture (fault), especially in brittle natural rocks. Firstly, uniaxial compression tests are conducted on marble specimens containing en-echelon flaws. The latter is cut by using the water abrasive jet into the rock specimens. The fracturing processes of these specimens leading to the formation of a fault are observed in detail by the use of a high speed camera. The influences of the flaw geometry on the production of tensile cracks and shear cracks, which in turn dictate the coalescence patterns of the entire set of en-echelon flaws are comprehensively studied. Secondly, a numerical study based on a recently developed contact model, flat-joint contact model using the discrete element method (DEM) is carried out to model the present laboratory experiments. The numerical results provide a quantitative assessment of the interaction of en-echelon flaws. Particularly, the evolution of the stress field, as well as the characteristics of new crack initiation, propagation and coalescence associated with the generation of an eventual shear rupture are studied in detail. The numerical results are found to agree well with the experimental results obtained in both microscopic and macroscopic observations.

Keywords: discrete element method, en-echelon flaws, fault, marble

Procedia PDF Downloads 254

Authors: Ehsan Mohseni

Abstract:

The aim of this thesis is to provide numerical analyses of reinforced concrete beams-column joints with/without CFRP (Carbon Fiber Reinforced Polymer) in order to achieve a better understanding of the behaviour of strengthened beamcolumn joints. A comprehensive literature survey prior to this study revealed that published studies are limited to a handful only; the results are inconclusive and some are even contradictory. Therefore in order to improve on this situation, following that review, a numerical study was designed and performed as presented in this thesis. For the numerical study, dimensions, end supports, and characteristics of the beam and column models were the same as those chosen in an experimental investigation performed previously where ten beamcolumn joint were tested tofailure. Finite element analysis is a useful tool in cases where analytical methods are not capable of solving the problem due to the complexities associated with the problem. The cyclic behaviour of FRP strengthened reinforced concrete beam-columns joints is such a case. Interaction of steel (longitudinal and stirrups), concrete and FRP, yielding of steel bars and stirrups, cracking of concrete, the redistribution of stresses as some elements unload due to crushing or yielding and the confinement of concrete due to the presence of FRP are some of the issues that introduce the complexities into the problem.Numerical solutions, however, can provide further in formation about the behaviour in lieu of the costly experiments or complex closed form solutions. This thesis presents the results of a numerical study on beam-column joints subjected to cyclic loads that are strengthened with CFRP wraps or strrips in a variety of configurations. The analyses are performed by Abaqus finite element program and are calibrated with the experiments. A range of issues in beam-column joints including the cracking load, the ultimate load, lateral load-displacement curves of joints, are investigated.The numerical results for different configurations of strengthening are compared. Finally, the computed numerical results are compared with those obtained from experiments. the cracking load, the ultimate load, lateral load-displacement curves obtained from numerical analysis for all joints were in very good agreement with the corresponding experimental ones.The results obtained from the numerical analysis in most cases implies that this method is conservative and therefore can be used in design applications with confidence.

Keywords: numerical analysis, strengthening, CFRP, reinforced concrete joints

Procedia PDF Downloads 346

Authors: Akulov M. A., Orlova O. R., Zaharov V. O., Tomskij A. A.

Abstract:

Introduction: One of the common postoperative complications of posterior cranial fossa (PCF) and cerebello-pontine angle tumor treatment is a facial nerve palsy, which leads to multiple and resistant to treatment impairments of mimic muscles structure and functions. After 4-6 months after facial nerve palsy with insufficient therapeutic intervention patients develop a postparalythic syndrome, which includes such symptoms as mimic muscle insufficiency, mimic muscle contractures, synkinesis and spontaneous muscular twitching. A novel method of treatment is the use of a recent local neuromuscular blocking agent– botulinum toxin A (BTA). Experience of BTA treatment enables an assumption that it can be successfully used in late facial nerve palsy complications to significantly increase quality of life of patients. Study aim. To evaluate the efficacy of botulinum toxin A (BTA) (Xeomin) treatment in patients with late facial nerve palsy complications. Patients and Methods: 31 patients aged 27-59 years 6 months after facial nerve palsy development were evaluated. All patients received conventional treatment, including massage, movement therapy etc. Facial nerve palsy developed after acoustic nerve tumor resection in 23 (74,2%) patients, petroclival meningioma resection – in 8 (25,8%) patients. The first group included 17 (54,8%) patients, receiving BT-therapy; the second group – 14 (45,2%) patients continuing conventional treatment. BT-injections were performed in synkinesis or contracture points 1-2 U on injured site and 2-4 U on healthy side (for symmetry). Facial nerve function was evaluated on 2 and 4 months of therapy according to House-Brackman scale. Pain syndrome alleviation was assessed on VAS. Results: At baseline all patients in the first and second groups demonstrated аpostparalytic syndrome. We observed a significant improvement in patients receiving BTA after only one month of treatment. Mean VAS score at baseline was 80,4±18,7 and 77,9±18,2 in the first and second group, respectively. In the first group after one month of treatment we observed a significant decrease of pain syndrome – mean VAS score was 44,7±10,2 (р<0,01), whereas in the second group VAS score was as high as 61,8±9,4 points (p>0,05). By the 3d month of treatment pain syndrome intensity continued to decrease in both groups, but, the first group demonstrated significantly better results; mean score was 8,2±3,1 and 31,8±4,6 in the first and second group, respectively (р<0,01). Total House-Brackman score at baseline was 3,67±0,16 in the first group and 3,74±0,19 in the second group. Treatment resulted in a significant symptom improvement in the first group, with no improvement in the second group. After 4 months of treatment House-Brockman score in the first group was 3,1-fold lower, than in the second group (р<0,05). Conclusion: Botulinum toxin injections decrease postparalytic syndrome symptoms in patients with facial nerve palsy.

Keywords: botulinum toxin, facial nerve palsy, postparalytic syndrome, synkinesis

Procedia PDF Downloads 292

Authors: Kwei Huan Liw, Sashi B. Darshan

Abstract:

Background: Double eyelid surgery has become one of the most sought-after aesthetic procedures among Asians. Many surgeons perform surgical blepharoplasty and various other methods of non-incisional blepharoplasty. Face-Q is a validated method of measuring patient satisfaction for facial aesthetic procedures. Here we have analyzed the overall eye satisfaction score, the upper eyelid appraisal score and the adverse effect on eyes score Methods: 274 patients (548 eyes), aged between 18 to 40 years old, were recruited from 2015-2018. Each patient underwent a non-incisional double-eyelid blepharoplasty using a single-knotted continuous buried suture. 3 – 5 stab incisions were made depending on the upper eyelid size. A needle loaded with 7-0 nylon is passed from the lateral most wound through the dermis and the conjunctiva in an alternate fashion into the remaining stab wounds. The suture is then tunneled back laterally in the deeper dermis and knotted securely with the suture end. The knot is then buried within the orbicularis oculi muscle. Each patient was required to fill the Face-Q questionnaire before the procedure and 2 weeks post procedure. The results are described based on the percentage of the maximum achievable score. Patients were reviewed after 12 to 18 months to assess the long-term outcome. Results: The overall eye satisfaction score demonstrated a high level of post-operative satisfaction (97.85%), compared to 27.32% pre-operatively. The appraisal of upper eyelid scores showed drastic improvement in perception post-operatively (95.31%) compared to 21.44% pre-operatively. Adverse effect on eyes score showed a very low post-operative complication rate (0.4%) The long-term follow-up showed 6 cases that had developed asymmetrical folds. Only 1 patient agreed for revision surgery. The other 5 patients were still satisfied with the outcome and were not keen for revision surgery. None of the cases had loosening of knots. Conclusion: Modified single-knot continuous buried suture technique is a simple and non-invasive method to create aesthetically pleasing non-surgical double-eyelids, which has long-term effects. Proper patient selection is crucial and good surgical technique is required to achieve a desirable outcome.

Keywords: blepharoplasty, double-eyelid, face-Q, non-incisional

Procedia PDF Downloads 117

Authors: Sadia Arshad, Ayesha Sohail, Sana Javed, Khadija Maqbool, Salma Kanwal

Abstract:

The dynamical study of the carriers play an essential role in the evolution and global transmission of infectious diseases and will be discussed in this study. To make this approach novel, we will consider the fractional order model which is generalization of integer order derivative to an arbitrary number. Since the integration involved is non local therefore this property of fractional operator is very useful to study epidemic model for infectious diseases. An extended numerical method (ODE solver) is implemented on the model equations and we will present the simulations of the model for different values of fractional order to study the effect of carriers on transmission dynamics. Global dynamics of fractional model are established by using the reproduction number.

Keywords: Fractional differential equation, Numerical simulations, epidemic model, transmission dynamics

Procedia PDF Downloads 594

Authors: Adisai Thovicha

Abstract:

This study is the survey research, designed to study the work happiness level of personnel at Suan Sunandha Rajabhat University. The sample group consisted of 329 personnel. The results were collected by stratified sampling, using work positions for each stage. The results were analyzed and calculated by computer program. Statistics used during analyzing were percentage, mean, and standard deviation. From the study, the work happiness level of personnel were in very high score range in both overall and specific category. The top category which received the most score was positive attitude, work satisfaction, life satisfaction, and negative attitude.

Keywords: work happiness, Suan Sunandha Rajabhat University, personnel, positive attitude

Procedia PDF Downloads 371

Authors: Lama Bendak

Abstract:

Parents and teachers face major problems dealing with attention deficit hyperactivity students. One solution is by changing the school to a less restrictive one or leaving school for good. The purpose of this study is to highlight the importance and role of individual educational plans (IEP) in helping cycle one ages six to nine attention deficit hyperactivity disorder (ADHD) students on the behavioral level. We have adopted the qualitative approach experimental where the total number of the students in our field of study was 66 from four schools. We have limited our study to cycle one students; that is grades 1, 2 and 3, whose ages range from 5.5 to 8.5. We divided the students into two groups where the controlled group was 36 students, and the experimental group was 30 students. The measuring instrument or tool that we used in our study is The SNAP-IV Teacher and Parents Rating Scale and was filled by class teachers. We did the pretest during the first trimester of the school year. Then we applied the Individual Educational Plans IEP's for two trimesters. Then we did the posttest and submitted the results for analysis, where we used the ANCOVA. The results of this study showed that the IEP's efficacy in helping ADHD students on the behavioral aspect showed statistical differences and varied depending on the initial level of difficulty of the student.

Keywords: attention deficit hyperactivity disorder, individual educational plans, behavioral charts, SNAP-IV teacher and parents rating scale

Procedia PDF Downloads 285

Authors: Petar Dobrev

Abstract:

There is no agreed-upon definition of firm quality. While profitability and stock performance often qualify as popular proxies of quality, in this project, we aim to identify quality without relying on a firm’s financial statements or stock returns as selection criteria. Instead, we use firm-level data on management practices across small to medium-sized U.S. manufacturing firms from the World Management Survey (WMS) to measure firm quality. Each firm in the WMS dataset is assigned a mean management score from 0 to 5, with higher scores identifying better-managed firms. This management score serves as our proxy for firm quality and is the sole criteria we use to separate firms into portfolios comprised of high-quality and low-quality firms. We define high-quality (low-quality) firms as those firms with a management score of one standard deviation above (below) the mean. To study whether this proxy for firm quality can identify better-performing firms, we link this data to Compustat and The Center for Research in Security Prices (CRSP) to obtain firm-level data on financial performance and monthly stock returns, respectively. We find that from 1999 to 2019 (our sample data period), firms in the high-quality portfolio are consistently more profitable — higher operating profitability and return on equity compared to low-quality firms. In addition, high-quality firms also exhibit a lower risk of bankruptcy — a higher Altman Z-score. Next, we test whether the stocks of the firms in the high-quality portfolio earn superior risk-adjusted excess returns. We regress the monthly excess returns on each portfolio on the Fama-French 3-factor, 4-factor, and 5-factor models, the betting-against-beta factor, and the quality-minus-junk factor. We find no statistically significant differences in excess returns between both portfolios, suggesting that stocks of high-quality (well managed) firms do not earn superior risk-adjusted returns compared to low-quality (poorly managed) firms. In short, our proxy for firm quality, the WMS management score, can identify firms with superior financial performance (higher profitability and reduced risk of bankruptcy). However, our management proxy cannot identify stocks that earn superior risk-adjusted returns, suggesting no statistically significant relationship between managerial quality and stock performance.

Keywords: excess stock returns, management, profitability, quality

Procedia PDF Downloads 89

Authors: N. Benmebarek, F. Berrabah, S. Benmebarek

Abstract:

This paper is interested by numerical analysis using PLAXIS code of geosynthetic reinforced embankment crossing a section about 11 km on sabkha soil of Chott El Hodna in Algeria. The site observations indicated that the surface soil of this sabkha is very sensitive to moisture and complicated by the presence of locally weak zones. Therefore, serious difficulties were encountered during building the first embankment layer. This paper focuses on the use of geosynthetic to mitigate the difficulty encountered. Due to the absence of an accepted design methods, parametric studies are carried out to assess the effect of basal embankment reinforcement on both the bearing capacity and compaction conditions. The results showed the contribution conditions of geosynthetics to improve the bearing capacity of sabkha soil.

Keywords: reinforced embankment, numerical modelling, geosynthetics, weak bearing capacity

Procedia PDF Downloads 295

Authors: S. H. Atef, N. H. Mahmoud, S. Abdrahman, A. Fattoh

Abstract:

Background: The aim of the study is to assess the diagnostic value of fibrotest and hyaluronic acid in discriminate between insignificant and significant fibrosis. Also, to find out if these parameters could replace liver biopsy which is currently used for selection of chronic hepatitis C patients eligible for antiviral therapy. Study design: This study was conducted on 52 patients with HCV RNA detected by polymerase chain reaction (PCR) who had undergone liver biopsy and attending the internal medicine clinic at Ain Shams University Hospital. Liver fibrosis was evaluated according to the METAVIR scoring system on a scale of F0 to F4. Biochemical markers assessed were: alpha-2 macroglobulin (α2-MG), apolipoprotein A1 (Apo-A1), haptoglobin, gamma-glutamyl transferase (GGT), total bilirubin (TB) and hyaluronic acid (HA). The fibrotest score was computed after adjusting for age and gender. Predictive values and ROC curves were used to assess the accuracy of fibrotest and HA results. Results: For fibrotest, the observed area under curve for the discrimination between minimal or no fibrosis (F0-F1) and significant fibrosis (F2-F4) was 0.6736 for cutoff value 0.19 with sensitivity of 84.2% and specificity of 85.7%. For HA, the sensitivity was 89.5% and specificity was 85.7% and area under curve was 0.540 at the best cutoff value 71 mg/dL. Multi-use of both parameters, HA at 71 mg/dL with fibrotest score at 0.22 give a sensitivity 89.5%, specificity 100 and efficacy 92.3% (AUC 0.895). Conclusion: The use of both fibrotest score and HA could be as alternative to biopsy in most patients with chronic hepaitis C putting in consideration some limitations of the proposed markers in evaluating liver fibrosis.

Keywords: fibrotest, liver fibrosis, HCV RNA, biochemical markers

Procedia PDF Downloads 284

Authors: F. Rahimi Dehgolan, M. Behzadi, J. Fathi Sola

Abstract:

In this article, the Johnson-Cook material model’s constants for structural steel ST.37 have been determined by a method which integrates experimental tests, numerical simulation, and optimization. In the first step, a quasi-static test was carried out on a plain specimen. Next, the constants were calculated for it by minimizing the difference between the results acquired from the experiment and numerical simulation. Then, a quasi-static tension test was performed on three notched specimens with different notch radii. At last, in order to verify the results, they were used in numerical simulation of notched specimens and it was observed that experimental and simulation results are in good agreement. Changing the diameter size of the plain specimen in the necking area was set as the objective function in the optimization step. For final validation of the proposed method, diameter variation was considered as a parameter and its sensitivity to a change in any of the model constants was examined and the results were completely corroborating.

Keywords: constants, Johnson-Cook material model, notched specimens, quasi-static test, sensitivity

Procedia PDF Downloads 305

Authors: S. Öcal, A. Erakgün, E. Yüksel, M. N. Deniz, E. Erhan, A. Çertuğ

Abstract:

Background: Emergence agitation (EA) is defined as a dissociated state of consciousness during the early post-anesthesia period in which the child is inconsolable, irritable, uncompromising or uncooperative, typically thrashing, crying, moaning, or incoherent, and not recognizing or identifying familiar and known objects or people. Some studies found preoperative parental anxiety to be a predictor of EA. Methods: Seventy-four children, between the ages of 3-12 undergoing adenoidectomy/tonsillectomy at Ege University Hospital, were studied. Anesthesia was induced and maintained using 2% sevoflurane in 50% oxygen and 50% air following a premedicative dose of 0.5mg/kg oral midazolam. After the children were taken into the operating theater, the mothers were given the State-Trait Anxiety Inventory (STAI) questionnaire. To evaluate EA, Post Anesthetic Emergence Delirium (PAED) score of the children were noted every 10min during the first 30min of the postoperative period. EA was defined with a highest PAED score of ≥ 10, and non-EA with a highest PAED score of ≤ 9. Results: In this study, the incidence of postoperative EA was 31% (34% under the age of 6 and 19% over). Mothers of children with EA were found not to be significantly more anxious on STAI compared to mothers of non-EA children. Conclusions: Contrary to some earlier studies, we were unable to find an association between preoperative parental anxiety and postoperative EA.

Keywords: parental anxiety, emergence agittion, Post Anesthetic Emergence Delirium, anesthesia

Procedia PDF Downloads 338

Authors: A. Golshani, M. Gharizade Varnusefaderani, S. Majidian

Abstract:

Underground structures are of those structures that have uncertainty in design procedures. That is due to the complexity of soil condition around. Under passing tunnels are also such affected structures. Despite geotechnical site investigations, lots of uncertainties exist in soil properties due to unknown events. As results, it possibly causes conflicting settlements in numerical analysis with recorded values in the project. This paper aims to report a case study on a specific under passing tunnel constructed by New Austrian Tunnelling Method in Iran. The intended tunnel has an overburden of about 11.3m, the height of 12.2m and, the width of 14.4m with 2.5 traffic lane. The numerical modeling was developed by a 2D finite element program (PLAXIS Version 8). Comparing displacement histories at the ground surface during the entire installation of initial lining, the estimated surface settlement was about four times the field recorded one, which indicates that some local unknown events affect that value. Also, the displacement ratios were in a big difference between the numerical and field data. Consequently, running several numerical back analyses using laboratory and field tests data, the geotechnical parameters were accurately revised to match with the obtained monitoring data. Finally, it was found that usually the values of soil parameters are conservatively low-estimated up to 40 percent by typical engineering judgment. Additionally, it could be attributed to inappropriate constitutive models applied for the specific soil condition.

Keywords: NATM, surface displacement history, numerical back-analysis, geotechnical parameters

Procedia PDF Downloads 191

Authors: Tania Mannan, Rahelee Zinnat, Fatema Jebunnesa, Israt Ara Hossain

Abstract:

Background: Exposure to arsenic has known toxic effects but the effect on pregnancy outcomes is not as widely documented especially in women with diabetes. Growing evidence has suggested a potential role of arsenic exposure in the development of gestational diabetes mellitus (GDM). Therefore, we aimed to investigate the association of urinary arsenic (UAs) with birth outcomes in GDM subjects. Methods: Under an observational cross-sectional design a total of 263 GDM subjects (age in years, M±SD, 21±3.7) residing in an arsenic affected area of Bangladesh, were subjected to a 2 sample OGTT at the third trimester of gestation. Among them, 73 GDM and 190 non-GDM subjects enrolled in this study. Clinical and anthropometric measurements were done by standard techniques. Degree of chronic arsenic exposure was assessed by the level of UAs level. According to World Health Organization (WHO) criteria, GDM was diagnosed and neonatal outcomes using APGAR (Activity Pulse Grimace Appearance Respirations) Score, birth weight and size were assessed by a specialist obstetrician. Serum glucose was measured by the Glucose Oxidase method and UAs level was determined by ultraviolet/visible spectrophotometry. Result: Out of the 263 pregnant women, 28% developed GDM. Urinary Arsenic was significantly higher in the GDM as compared to the non-GDM group [UAs, µg/l, M±SD (range), 204.2±67.0 (67.0-377.0) vs 77.3±38.1 (22.0-99.0), p < 0.001]. Activity Pulse Grimace Appearance Respirations Score of the neonates from GDM mothers was significantly lower compared to the neonates from non-GDM mothers [APGAR Score, M±SD, 4.7±0.8 vs. 6.4±0.7, p<0.001]. Pearson’s correlation analysis in GDM subjects revealed that UA levels were found to have a significant positive correlation with both fasting and postprandial serum glucose levels (p < 0.001) and (p < 0.001) respectively. Again, a significant inverse correlation of UAs with birth weight and size was observed (p < 0.001). The APGAR Score of the neonates were found to have a significant negative correlation (p < 0.001) with UAs level. Conclusion: The effect of chronic arsenic exposure is associated with glucose intolerance during pregnancy and it also adversely affects birth outcomes. The study suggests further research on the impact of total arsenic exposure on pregnancy outcomes.

Keywords: APGAR score, arsenic exposure, birth outcome, gestational diabetes mellitus,

Procedia PDF Downloads 127

Authors: Mayur Kudale, Priyanka Panchal

Abstract:

Cellulose fibres, mainly cotton, are the most important kind of fibre used for manufacturing shirting fabric. However, to overcome its main disadvantage, that is it gets wrinkled after washing, is to use special kind of finish which is resin finish. This finish provides a resistance against shrinkage along with improved wet and dry wrinkle recovery to cellulosic textiles. The Durable Press (DP) finish uses a mechanism of cross-linking with polymers or resin to inhibit the easy movement of the cellulose chains. The purpose of these experimentations on the weave is to observe and compare the variations in properties after DP finish without adverse effect on strength of the fabric. In this work, we have prepared three types of fabric weaves viz. Plain, Twill and Sateen with their construction parameters intact. To get the projected results, this work uses three types of variables viz. concentration of Resin, Temperature and Time. Resultant of these variables is only change in weave or construction on DP finish which further opens the possibilities of improvement of DP either of mentioned weaves. The combined effect of such various parametric resin finish methodology will give the best method to improve the DP. However, the DP finish can cause a side effect of reduction in elasticity and flexibility of cellulosic fibres. The natural cellulose could loss abrasion resistance along with tear and tensile strength by applying DP finish. In this work, it is taken care that the tear strength of fabric will not drop below certain limit otherwise the fabric will tear down easily. In this work, it is found that there is a significant drop in tearing and tensile strength with the improvement of DP finish. Later on, it is also found that the twill weave has more percentage drop in tearing strength as compared to plain and sateen weave. There is major kind of observations obtained after this work. First, the mixing of cotton should be done properly to achieve the higher DP rating in plain weave. Second, the careful combination of warp, weft and fabric construction must be decided to avoid the high drop in tear and tensile strength in a twill weave. Third, the sateen weave has a good sheen and DP rating hence it can be used in shirting of gents and ladies dress materials. This concludes that to achieve higher DP ratings, use plain weave construction than twill and sateen because it has the lowest tear and tensile strength drop.

Keywords: concentration of resin, cross-linking, durable press (DP) finish, sheen, tear and tensile strength, weave

Procedia PDF Downloads 300

Authors: Mateusz Paszko, Konrad Pietrykowski, Krzysztof Skiba

Abstract:

Due to low-altitude and relatively low flight speed, today’s combat assets like missile weapons equipped with infrared guidance systems are one of the most important threats to the helicopters performing combat missions. Especially meaningful in helicopter aviation is infrared emission by exhaust gases, regressed to the surroundings. Due to high temperature, exhaust gases are a major factor in detectability of a helicopter performing air combat operations. This study presents the results of simulating the flow of the mixture of exhaust and air in the flow duct of an injective exhaust cooler, adapted to cooperate with the PZL 10W turbine engine. The simulation was performed using a numerical model and the ANSYS Fluent software. Simulation computations were conducted for set flight conditions of the PZL W-3 Falcon helicopter. The conclusions resulting from the conducted numerical computations should allow for optimisation of the flow duct geometry in the cooler, in order to achieve the greatest possible temperature reduction of exhaust exiting into the surroundings. It is expected that the obtained results should be useful for further works related to the development of the final version of exhaust cooler for the PZL W-3 Falcon helicopter.

Keywords: exhaust cooler, helicopter, numerical simulation, stealth

Procedia PDF Downloads 144

Authors: U. Narumitbowonkul, P. Keangin, P. Rattanadecho

Abstract:

Both numerical and experimental investigation of the temperature distribution and electric field in a natural rubber glove (NRG) during microwave heating are studied. A three-dimensional model of NRG and microwave oven are considered in this work. The influences of position, heating time and rotation angle of NRG on temperature distribution and electric field are presented in details. The coupled equations of electromagnetic wave propagation and heat transfer are solved using the finite element method (FEM). The numerical model is validated with an experimental study at a frequency of 2.45 GHz. The results show that the numerical results closely match the experimental results. Furthermore, it is found that the temperature distribution and electric field increases with increasing heating time. The hot spot zone appears in NRG at the tip of middle finger while the maximum temperature occurs in case of rotation angle of NRG = 60 degree. This investigation provides the essential aspects for a fundamental understanding of heat transport of NRG using microwave energy in industry.

Keywords: electric field, finite element method, microwave energy, natural rubber glove

Procedia PDF Downloads 259

Authors: Beata Jackowska-Zduniak

Abstract:

We formulate and analyze a mathematical model describing dynamics of cancer growth under the influence of radiation therapy. The effect of this type of therapy is considered as an additional equation of discussed model. Numerical simulations show that delay, which is added to ordinary differential equations and represent time needed for transformation from one type of cells to the other one, affects the behavior of the system. The validation and verification of proposed model is based on medical data. Analytical results are illustrated by numerical examples of the model dynamics. The model is able to reconstruct dynamics of treatment of cancer and may be used to determine the most effective treatment regimen based on the study of the behavior of individual treatment protocols.

Keywords: mathematical modeling, numerical simulation, ordinary differential equations, radiation therapy

Procedia PDF Downloads 403

Authors: Shumaila Zeb

Abstract:

The proposed study aims to investigate insolvency risk of commercial banks of Pakistan. Furthermore, it empirically estimates the effect of already implemented financial regulations on the insolvency risk of banks. To carry out the empirical analysis, a balanced bank-level panel data covering the period 2008-2016 is used. The Z-score is used for calculating the insolvency risk of each bank. The panel regression is used to investigate the relationship between financial regulations and insolvency risk of banks. The empirics reveal that the financial regulations enforced by State Bank of Pakistan have significant impacts on the insolvency risk of banks. The results further indicate that loan ratio and reserve ratio are positively and significantly related to the insolvency risk of banks.

Keywords: insolvency risk, Z-score, financial regulations, banks

Procedia PDF Downloads 194

Authors: Alia Alghosoun, Michael Herty, Mohammed Seaid

Abstract:

We present a new class of numerical techniques to solve shallow water flows over dry areas including run-up. Many recent investigations on wave run-up in coastal areas are based on the well-known shallow water equations. Numerical simulations have also performed to understand the effects of several factors on tsunami wave impact and run-up in the presence of coastal areas. In all these simulations the shallow water equations are solved in entire domain including dry areas and special treatments are used for numerical solution of singularities at these dry regions. In the present study we propose a new method to deal with these difficulties by reformulating the shallow water equations into a new system to be solved only in the wetted domain. The system is obtained by a change in the coordinates leading to a set of equations in a moving domain for which the wet/dry interface is the reconstructed using the wave speed. To solve the new system we present a finite volume method of Lax-Friedrich type along with a modified method of characteristics. The method is well-balanced and accurately resolves dam-break problems over dry areas.

Keywords: dam-break problems, finite volume method, run-up waves, shallow water flows, wet/dry interfaces

Procedia PDF Downloads 144

Authors: Orkun Yavuz, Ferhat Kadioğlu, M. Emin Ercan

Abstract:

This study aims to investigate the effects of repeated high loadings on the performance of adhesively-bonded Single Lap Joints (SLJs) by employing both experimental and numerical approaches. A projectile with a mass of 1.25 gr and density of 11.3 gr/cm3 was fired at the joints with a velocity of about 280 m/s using a specially designed experimental set-up, and the impact was recorded via a high-speed camera. The SLJs were manufactured from 6061 aluminum adherend (AA6061) material and an adhesive film. The joints, which have an adherend thickness of 4 mm and overlap length of 15 mm, were subjected to up to 3 shots for the ballistic test, followed by quasi-static tensile testing. The impacted joints, then, were compared to the non-impacted and one-shot impacted ones, which was a subject of investigation carried out before. It was found that while the joints subjected to 2 shots mechanically deteriorated, those subjected to 3 shots experienced a complete failure at the end of the experiment. A numerical study was also conducted using an ABAQUS package program. While the adherends were modelled using the Johnson-Cook deformation parameters, an elastoplastic behavior of the adhesive was used as input data in the analyses. It seems the experimental results confirm the numerical ones.

Keywords: ballistic tests, adhesive joints, numerical analysis, SLJ

Procedia PDF Downloads 61

Authors: Tharsinithevy Kirupananthan, Thivahary Geretharan

Abstract:

Since creation of agricultural enterprises going to reflect the micro and macro level development of Sri Lanka, it is vey important to study the entrepreneurial trends of Agricultural Undergraduates. Likert scale scoring method was used to assess the responses of involvement, Role model effect, aware of demands, confidence and willingness. 37.8% were strongly agreed to do full time business. The average score for to do agriculture businesses were between agree and strongly agree. The average scores for role model effects were less than agree. Average score for aware of needs of society was less than agree. 75.7% of them were able to identify the demands of the society. The demands identified were human capital, self sufficient domestic production, safe and nutritional foods. The confidence of having enough skills score was less than agree. 64.1% of them were owned special skills to carry out entrepreneurial activities. Such skills were possession of different human capitals management skills. The willingness responses scores were more than agree. 61.5% of them were discussed their business plan. Their dream plans were development of new food products, Quality planting materials, harmless method of cultivation and floricultural industry. Those were supported by government policies and other related organizations.

Keywords: agricultural undergraduates, entrepreneurial trends, likert scale Sri Lanka

Procedia PDF Downloads 387

Authors: Nana Adjoah Mbroh, Suares Clovis Oukouomi Noutchie

Abstract:

Singularly perturbed problems are parameter dependent problems, and they play major roles in the modelling of real-life situational problems in applied sciences. Thus, designing efficient numerical schemes to solve these problems is of much interest since the exact solutions of such problems may not even exist. Generally, singularly perturbed problems are identified by a small parameter multiplying at least the highest derivative in the equation. The presence of this parameter causes the solution of these problems to be characterized by rapid oscillations. This unique feature renders classical numerical schemes inefficient since they are unable to capture the behaviour of the exact solution in the part of the domain where the rapid oscillations are present. In this paper, a numerical scheme is proposed to solve a singularly perturbed Volterra Integro-differential equation. The scheme is based on the midpoint rule and employs the non-standard finite difference scheme to solve the differential part whilst the composite trapezoidal rule is used for the integral part. A fully fledged error estimate is performed, and Richardson extrapolation is applied to accelerate the convergence of the scheme. Numerical simulations are conducted to confirm the theoretical findings before and after extrapolation.

Keywords: midpoint rule, non-standard finite difference schemes, Richardson extrapolation, singularly perturbed problems, trapezoidal rule, uniform convergence

Procedia PDF Downloads 123

Authors: Florin Frunzulica, Alexandru Dumitrache, Octavian Preotu

Abstract:

The Coanda effect consists of the tendency of a jet to remain attached to a sufficiently long/large convex surface. Flows deflected by a curved surface have caused great interest during last fifty years a major interest in the study of this phenomenon is caused by the possibility of using this effect to aircraft with short take-off and landing, for thrust vectoring. It is also used in applications involving mixing two of more fluids, noise attenuation, ventilation, etc. The paper proposes the numerical study of an aerodynamic configuration that can passively amplify the Coanda effect. On a wing flaps with predetermined configuration, a channel is applied between two particular zones, a low-pressure one and a high-pressure another one, respectively. The secondary flow through this channel yields a gap between the jet and the convex surface, maintaining the jet attached on a longer distance. The section altering-based active control of the secondary flow through the channel controls the attachment of the jet to the surface and automatically controls the deviation angle of the jet. The numerical simulations have been performed in Ansys Fluent for a series of wing flaps-channel configurations with varying jet velocity. The numerical results are in good agreement with experimental results.

Keywords: blowing jet, CFD, Coanda effect, circulation control

Procedia PDF Downloads 343

Authors: Amani Waheed, Adel Mishriky, Rasha Farouk, Essam Abdallah, Sarah Hussein

Abstract:

Background: Occupational stress plays a crucial role in professional drivers' health. They are exposed to high workloads, low physical activity, high demand and low decisions as well as poor lifestyle factors including poor diet, sedentary work, and smoking. Dyslipidemia is a well-established modifiable cardiovascular risk factor. Occupational stress and other forms of chronic stress have been associated with raised levels of atherogenic lipids. Although stress management has some evidence in improving lipid profile, the association between occupational stress and dyslipidemia is not clear. Objectives: To assess the relational between occupational stress and lipid profile among professional drivers. Methodology: A cross-sectional study conducted at a large company in Ismailia City, Egypt, where, 131 professional drivers divided into 44 car drivers, 43 bus drivers, and 44 truck drivers were eligible after applying exclusion criteria. Occupational stress index (OSI), non-occupational risk factors of dyslipidemia were assessed using interview structured questionnaire. Blood pressure, body mass index (BMI) and lipid profile were measured. Results: The mean of total OSI score was 79.98 ± 6.14. The total OSI score is highest among truck drivers (82.16 ± 4.62), then bus drivers (80.26 ± 6.02) and lowest among car drivers (77.55 ± 6.79) with statistically significant. Eighty percent had Dyslipidemia. The duration of driving hours per day, exposure to passive smoking and increased BMI were the risk factors. No statistical significance between Total OSI score and dyslipidemia. Using, logistic regression analysis, occupational stress, duration of driving hours per day, and BMI were positive significant predictors for dyslipidemia. Conclusion: Professional drivers are exposed to occupational stress. A high proportion of drivers have dyslipidemia. Total OSI score doesn't have statistically significant relation with dyslipidemia.

Keywords: body mass index, dyslipidaemia, occupational stress, professional drivers

Procedia PDF Downloads 162

Authors: Yusuf Yilmaz, Gamze Gediz Ilis

Abstract:

Gas Nitrogen where has a boiling point of -189.52oC at atmospheric pressure widely used in the industry. Nitrogen that used in the industry should be transported in liquid form to the plant area. Ambient air vaporizer (AAV) generally used for vaporization of cryogenic gases such as liquid nitrogen (LN2), liquid oxygen (LOX), liquid natural gas (LNG), and liquid argon (LAR) etc. AAV is a group of star-shaped fin vaporizer. The design and the effect of the shape of fins of the vaporizer is one of the most important criteria for the performance of the vaporizer. In this study, the performance of AAV working with liquid nitrogen was analyzed numerically in a star-shaped aluminum finned pipe. The numerical analysis is performed in order to investigate the heat capacity of the vaporizer per meter pipe length. By this way, the vaporizer capacity can be predicted for the industrial applications. In order to achieve the validation of the numerical solution, the experimental setup is constructed. The setup includes a liquid nitrogen tank with a pressure of 9 bar. The star-shaped aluminum finned tube vaporizer is connected to the LN2 tank. The inlet and the outlet pressure and temperatures of the LN2 of the vaporizer are measured. The mass flow rate of the LN2 is also measured and collected. The comparison of the numerical solution is performed by these measured data. The ambient conditions of the experiment are given as boundary conditions to the numerical model. The surface tension and contact angle have a significant effect on the boiling of liquid nitrogen. Average heat transfer coefficient including convective and nucleated boiling components should be obtained for liquid nitrogen saturated flow boiling in the finned tube. Fluent CFD module is used to simulate the numerical solution. The turbulent k-ε model is taken to simulate the liquid nitrogen flow. The phase change is simulated by using the evaporation-condensation approach used with user-defined functions (UDF). The comparison of the numerical and experimental results will be shared in this study. Besides, the performance capacity of the star-shaped finned pipe vaporizer will be calculated in this study. Based on this numerical analysis, the performance of the vaporizer per unit length can be predicted for the industrial applications and the suitable pipe length of the vaporizer can be found for the special cases.

Keywords: liquid nitrogen, numerical modeling, two-phase flow, cryogenics

Procedia PDF Downloads 116

Authors: Ismail Aslantas

Abstract:

Value-Added Models (VAMs), the statistical methods for evaluating the effectiveness of teachers and schools based on student achievement growth, has attracted decision-makers’ and researchers’ attention over the last decades. As a result of this attention, many studies have conducted in recent years to discuss these statistical models from different aspects. This research focused on the importance of conceptual variables in VAM estimations; therefor, this research was undertaken to examine the extent to which value-added effectiveness estimates for teachers can be affected by using context predictions. Using longitudinal data over three years from the international school context, value-added teacher effectiveness was estimated by ordinary least-square value-added models, and the effectiveness of the teachers was examined. The longitudinal dataset in this study consisted of three major sources: students’ attainment scores up to three years and their characteristics, teacher background information, and school characteristics. A total of 1,027 teachers and their 35,355 students who were in eighth grade were examined for understanding the impact of model specifications on the value-added teacher effectiveness evaluation. Models were created using selection methods that adding a predictor on each step, then removing it and adding another one on a subsequent step and evaluating changes in model fit was checked by reviewing changes in R² values. Cohen’s effect size statistics were also employed in order to find out the degree of the relationship between teacher characteristics and their effectiveness. Overall, the results indicated that prior attainment score is the most powerful predictor of the current attainment score. 47.1 percent of the variation in grade 8 math score can be explained by the prior attainment score in grade 7. The research findings raise issues to be considered in VAM implementations for teacher evaluations and make suggestions to researchers and practitioners.

Keywords: model specification, teacher effectiveness, teacher performance evaluation, value-added model

Procedia PDF Downloads 129

Authors: Musa D. Aliyu, Ouahid Harireche, Colin D. Hills

Abstract:

The incapability of supercritical C02 to transport and dissolve mineral species from the geothermal reservoir to the fracture apertures and other important parameters in heat mining makes it an attractive substance for Heat extraction from hot dry rock. In other words, the thermodynamic efficiency of hot dry rock (HDR) reservoirs also increases if supercritical C02 is circulated at excess temperatures of 3740C without the drawbacks connected with silica dissolution. Studies have shown that circulation of supercritical C02 in homogenous geothermal reservoirs is quite encouraging; in comparison to that of the water. This paper aims at investigating the aforementioned processes in the case of the heterogeneous geothermal reservoir located at the Soultz site (France). The MultiPhysics finite element package COMSOL with an interface of coupling different processes encountered in the geothermal reservoir stimulation is used. A fully coupled numerical model is developed to study the thermal and hydraulic processes in order to predict the long-term operation of the basic reservoir parameters that give optimum energy production. The results reveal that the temperature of the SCC02 at the production outlet is higher than that of water in long-term stimulation; as the temperature is an essential ingredient in rating the energy production. It is also observed that the mass flow rate of the SCC02 is far more favourable compared to that of water.

Keywords: FEM, HDR, heterogeneous reservoir, stimulation, supercritical C02

Procedia PDF Downloads 380

Authors: Oliver Chunho Ma, Tszying Chang

Abstract:

Background: Traditional Chinese Medicine (TCM) has been widely used in the treatment of eczema. However, there is currently a lack of comprehensive research on the overall effectiveness of TCM in treating eczema, particularly using the Eczema Area and Severity Index (EASI) score as an evaluation tool. Meta-analysis can integrate the results of multiple studies to provide more convincing evidence. Objective: To conduct a systematic review and meta-analysis based on the EASI score to evaluate the overall effectiveness of TCM in the treatment of eczema. Specifically, the study will review and analyze published clinical studies that investigate TCM treatments for eczema and use the EASI score as an outcome measure, comparing the differences in improving the severity of eczema between TCM and other treatment modalities, such as conventional Western medicine treatments. Methods: Relevant studies, including randomized controlled trials (RCTs) and non-randomized controlled trials, that involve TCM treatment for eczema and use the EASI score as an outcome measure will be searched in medical literature databases such as PubMed, CNKI, etc. Relevant data will be extracted from the selected studies, including study design, sample size, treatment methods, improvement in EASI score, etc. The methodological quality and risk of bias of the included studies will be assessed using appropriate evaluation tools (such as the Cochrane Handbook). The results of the selected studies will be statistically analyzed, including pooling effect sizes (such as standardized mean differences, relative risks, etc.), subgroup analysis (e.g., different TCM syndromes, different treatment modalities), and sensitivity analysis (e.g., excluding low-quality studies). Based on the results of the statistical analysis and quality assessment, the overall effectiveness of TCM in improving the severity of eczema will be interpreted. Expected outcomes: By integrating the results of multiple studies, we expect to provide more convincing evidence regarding the specific effects of TCM in improving the severity of eczema. Additionally, subgroup analysis and sensitivity analysis can further elucidate whether the effectiveness of TCM treatment is influenced by different factors. Besides, we will compare the results of the meta-analysis with the clinical data from our clinic. For both the clinical data and the meta-analysis results, we will perform descriptive statistics such as means, standard deviations, percentages, etc. and compare the differences between the two using statistical tests such as independent samples t-test or non-parametric tests to assess the statistical differences between them.

Keywords: Eczema, traditional Chinese medicine, EASI, systematic review, meta-analysis

Procedia PDF Downloads 51