Search results for: loss estimation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5127

Search results for: loss estimation

3897 Medical Complications in Diabetic Recipients after Kidney Transplantation

Authors: Hakan Duger, Alparslan Ersoy, Canan Ersoy

Abstract:

Diabetes mellitus is the most common etiology of end-stage renal disease (ESRD). Also, diabetic nephropathy is the etiology of ESRD in approximately 23% of kidney transplant recipients. A successful kidney transplant improves the quality of life and reduces the mortality risk for most patients. However, patients require close follow-up after transplantation due to medical complications. Diabetes mellitus can affect patient morbidity and mortality due to possible effects of immunosuppressive therapy on glucose metabolism. We compared the frequency of medical complications and the outcomes in diabetic and non-diabetic kidney transplant recipients. Materials and Methods: This retrospective study conducted in 498 patients who underwent kidney transplant surgery at our center in 10-year periods. The patients were divided into two groups: diabetics (46 ± 10 year, 26 males, 16 females) and non-diabetics (39 ± 12 year, 259 males, 197 females). The medical complications, graft functions, causes of graft loss and death were obtained from medical records. Results: There was no significant difference between recipient age, duration of dialysis, body mass index, gender, donor type, donor age, dialysis type, histories of HBV, HCV and coronary artery disease between two groups. The history of hypertension in diabetics was higher (69% vs. 36%, p < 0.001). The ratios of hypertension (50.1% vs. 57.1%), pneumonia (21.9% vs. 20%), urinary infection (16.9% vs. 20%), transaminase elevation (11.5% vs. 20%), hyperpotasemia (14.7% vs. 17.1%), hyponatremia (9.7% vs. 20%), hypotension (7.1% vs. 7.9%), hypocalcemia (1.4% vs. 0%), thrombocytopenia (8.6% vs. 8.6%), hypoglycemia (0.7% vs. 0%) and neutropenia (1.8% vs. 0%) were comparable in non-diabetic and diabetic groups, respectively. The frequency of hyperglycaemia in diabetics was higher (8.6% vs. 54.3%, p < 0.001). After transplantation, primary non-function (3.4% vs. 2.6%), delayed graft function (25.1% vs. 34.2%) and acute rejection (7.3% vs. 10.5%) ratios of in non-diabetic and diabetic groups were similar, respectively. Hospitalization durations in non-diabetics and diabetics were 22.5 ± 17.5 and 18.7 ± 13 day (p=0.094). Mean serum creatinine levels in non-diabetics and diabetics were 1.54 ± 0.74 and 1.52 ± 0.62 mg/dL at 6th month. Forty patients had graft loss. The ratios of graft loss and death in non-diabetic and diabetic groups were 8.2% vs. 7.1% and 7.1% vs. 2.6% (p > 0.05). There was no significant relationship between graft and patient survivals with the development of medical complication. Conclusion: As a result, medical complications are common in the early period. Hyperglycaemia was frequently seen following transplantation due to the effects of immunosuppressant regimens. However, the frequency of other medical complications in diabetic patients did not differ from non-diabetic one. The most important cause of death is still infections. The development of medical complications during the first 6 months did not significantly affect transplant outcomes.

Keywords: kidney transplantation, diabetes mellitus, complication, graft function

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3896 Laparoscopic Proximal Gastrectomy in Gastroesophageal Junction Tumours

Authors: Ihab Saad Ahmed

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Background For Siewert type I and II gastroesophageal junction tumor (GEJ) laparoscopic proximal gastrectomy can be performed. It is associated with several perioperative benefits compared with open proximal gastrectomy. The use of laparoscopic proximal gastrectomy (LPG) has become an increasingly popular approach for select tumors Methods We describe our technique for LPG, including the preoperative work-up, illustrated images of the main principle steps of the surgery, and our postoperative course. Results Thirteen pts (nine males, four female) with type I, II (GEJ) adenocarcinoma had laparoscopic radical proximal gastrectomy and D2 lymphadenectomy. All of our patient received neoadjuvant chemotherapy, eleven patients had intrathoracic anastomosis through mini thoracotomy (two hand sewn end to end anastomoses and the other 9 patient end to side using circular stapler), two patients with intrathoracic anastomosis had flap and wrap technique, two patients had thoracoscopic esophageal and mediastinal lymph node dissection with cervical anastomosis The mean blood loss 80ml, no cases were converted to open. The mean operative time 250 minute Average LN retrieved 19-25, No sever complication such as leakage, stenosis, pancreatic fistula ,or intra-abdominal abscess were reported. Only One patient presented with empyema 1.5 month after discharge that was managed conservatively. Conclusion For carefully selected patients, LPG in GEJ tumour type I and II is a safe and reasonable alternative for open technique , which is associated with similar oncologic outcomes and low morbidity. It showed less blood loss, respiratory infections, with similar 1- and 3-year survival rates.

Keywords: LPG(laparoscopic proximal gastrectomy, GEJ( gastroesophageal junction tumour), d2 lymphadenectomy, neoadjuvant cth

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3895 A Posterior Predictive Model-Based Control Chart for Monitoring Healthcare

Authors: Yi-Fan Lin, Peter P. Howley, Frank A. Tuyl

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Quality measurement and reporting systems are used in healthcare internationally. In Australia, the Australian Council on Healthcare Standards records and reports hundreds of clinical indicators (CIs) nationally across the healthcare system. These CIs are measures of performance in the clinical setting, and are used as a screening tool to help assess whether a standard of care is being met. Existing analysis and reporting of these CIs incorporate Bayesian methods to address sampling variation; however, such assessments are retrospective in nature, reporting upon the previous six or twelve months of data. The use of Bayesian methods within statistical process control for monitoring systems is an important pursuit to support more timely decision-making. Our research has developed and assessed a new graphical monitoring tool, similar to a control chart, based on the beta-binomial posterior predictive (BBPP) distribution to facilitate the real-time assessment of health care organizational performance via CIs. The BBPP charts have been compared with the traditional Bernoulli CUSUM (BC) chart by simulation. The more traditional “central” and “highest posterior density” (HPD) interval approaches were each considered to define the limits, and the multiple charts were compared via in-control and out-of-control average run lengths (ARLs), assuming that the parameter representing the underlying CI rate (proportion of cases with an event of interest) required estimation. Preliminary results have identified that the BBPP chart with HPD-based control limits provides better out-of-control run length performance than the central interval-based and BC charts. Further, the BC chart’s performance may be improved by using Bayesian parameter estimation of the underlying CI rate.

Keywords: average run length (ARL), bernoulli cusum (BC) chart, beta binomial posterior predictive (BBPP) distribution, clinical indicator (CI), healthcare organization (HCO), highest posterior density (HPD) interval

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3894 Forensic Entomology in Algeria

Authors: Meriem Taleb, Ghania Tail, Fatma Zohra Kara, Brahim Djedouani, T. Moussa

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Forensic entomology is the use of insects and their arthropod relatives as silent witnesses to aid legal investigations by interpreting information concerning a death. The main purpose of forensic entomology is to establish the postmortem interval or PMI Postmortem interval is a matter of crucial importance in the investigations of homicide and other untimely deaths when the body found is after three days. Forensic entomology has grown immensely as a discipline in the past thirty years. In Algeria, forensic entomology was introduced in 2010 by the National Institute for Criminalistics and Criminology of the National Gendarmerie (NICC). However, all the work that has been done so far in this growing field in Algeria has been unknown at both the national and international levels. In this context, the aim of this paper is to describe the state of forensic entomology in Algeria. The Laboratory of Entomology of the NICC is the only one of its kind in Algeria. It started its activities in 2010, consisting of two specialists. The main missions of the laboratory are estimation of the PMI by the analysis of entomological evidence, and determination if the body was moved. Currently, the laboratory is performing different tasks such as the expert work required by investigators to estimate the PMI using the insects. The estimation is performed by the accumulated degree days method (ADD) in most of the cases except for those where the cadaver is in dry decay. To assure the quality of the entomological evidence, crime scene personnel are trained by the laboratory of Entomology of the NICC. Recently, undergraduate and graduate students have been studying carrion ecology and insect activity in different geographic locations of Algeria using rabbits and wild boar cadavers as animal models. The Laboratory of Entomology of the NICC has also been involved in some of these research projects. Entomotoxicology experiments are also conducted with the collaboration of the Toxicology Department of the NICC. By dint of hard work that has been performed by the Laboratory of Entomology of the NICC, official bodies have been adopting more and more the use of entomological evidence in criminal investigations in Algeria, which is commendable. It is important, therefore, that steps are taken to fill in the gaps in the knowledge necessary for entomological evidence to have a useful future in criminal investigations in Algeria.

Keywords: forensic entomology, corpse, insects, postmortem interval, expertise, Algeria

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3893 Investigation of External Pressure Coefficients on Large Antenna Parabolic Reflector Using Computational Fluid Dynamics

Authors: Varun K, Pramod B. Balareddy

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Estimation of wind forces plays a significant role in the in the design of large antenna parabolic reflectors. Reflector surface accuracies are very sensitive to the gain of the antenna system at higher frequencies. Hence accurate estimation of wind forces becomes important, which is primary input for design and analysis of the reflector system. In the present work, numerical simulation of wind flow using Computational Fluid Dynamics (CFD) software is used to investigate the external pressure coefficients. An extensive comparative study has been made between the CFD results and the published wind tunnel data for different wind angle of attacks (α) acting over concave to convex surfaces respectively. Flow simulations using CFD are carried out to estimate the coefficients of Drag, Lift and Moment for the parabolic reflector. Coefficients of pressures (Cp) over the front and the rear face of the reflector are extracted over surface of the reflector to study the net pressure variations. These resultant pressure variations are compared with the published wind tunnel data for different angle of attacks. It was observed from the CFD simulations, both convex and concave face of reflector system experience a band of pressure variations for the positive and negative angle of attacks respectively. In the published wind tunnel data, Pressure variations over convex surfaces are assumed to be uniform and vice versa. Chordwise and spanwise pressure variations were calculated and compared with the published experimental data. In the present work, it was observed that the maximum pressure coefficients for α ranging from +30° to -90° and α=+90° was lower. For α ranging from +45° to +75°, maximum pressure coefficients were higher as compared to wind tunnel data. This variation is due to non-uniform pressure distribution observed over front and back faces of reflector. Variations in Cd, Cl and Cm over α=+90° to α=-90° was in close resemblance with the experimental data.

Keywords: angle of attack, drag coefficient, lift coefficient, pressure coefficient

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3892 The Economic Burden of Mental Disorders: A Systematic Review

Authors: Maria Klitgaard Christensen, Carmen Lim, Sukanta Saha, Danielle Cannon, Finley Prentis, Oleguer Plana-Ripoll, Natalie Momen, Kim Moesgaard Iburg, John J. McGrath

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Introduction: About a third of the world’s population will develop a mental disorder over their lifetime. Having a mental disorder is a huge burden in health loss and cost for the individual, but also for society because of treatment cost, production loss and caregivers’ cost. The objective of this study is to synthesize the international published literature on the economic burden of mental disorders. Methods: Systematic literature searches were conducted in the databases PubMed, Embase, Web of Science, EconLit, NHS York Database and PsychInfo using key terms for cost and mental disorders. Searches were restricted to 1980 until May 2019. The inclusion criteria were: (1) cost-of-illness studies or cost-analyses, (2) diagnosis of at least one mental disorder, (3) samples based on the general population, and (4) outcome in monetary units. 13,640 publications were screened by their title/abstract and 439 articles were full-text screened by at least two independent reviewers. 112 articles were included from the systematic searches and 31 articles from snowball searching, giving a total of 143 included articles. Results: Information about diagnosis, diagnostic criteria, sample size, age, sex, data sources, study perspective, study period, costing approach, cost categories, discount rate and production loss method and cost unit was extracted. The vast majority of the included studies were from Western countries and only a few from Africa and South America. The disorder group most often investigated was mood disorders, followed by schizophrenia and neurotic disorders. The disorder group least examined was intellectual disabilities, followed by eating disorders. The preliminary results show a substantial variety in the used perspective, methodology, costs components and outcomes in the included studies. An online tool is under development enabling the reader to explore the published information on costs by type of mental disorder, subgroups, country, methodology, and study quality. Discussion: This is the first systematic review synthesizing the economic cost of mental disorders worldwide. The paper will provide an important and comprehensive overview over the economic burden of mental disorders, and the output from this review will inform policymaking.

Keywords: cost-of-illness, health economics, mental disorders, systematic review

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3891 Effective Stacking of Deep Neural Models for Automated Object Recognition in Retail Stores

Authors: Ankit Sinha, Soham Banerjee, Pratik Chattopadhyay

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Automated product recognition in retail stores is an important real-world application in the domain of Computer Vision and Pattern Recognition. In this paper, we consider the problem of automatically identifying the classes of the products placed on racks in retail stores from an image of the rack and information about the query/product images. We improve upon the existing approaches in terms of effectiveness and memory requirement by developing a two-stage object detection and recognition pipeline comprising of a Faster-RCNN-based object localizer that detects the object regions in the rack image and a ResNet-18-based image encoder that classifies the detected regions into the appropriate classes. Each of the models is fine-tuned using appropriate data sets for better prediction and data augmentation is performed on each query image to prepare an extensive gallery set for fine-tuning the ResNet-18-based product recognition model. This encoder is trained using a triplet loss function following the strategy of online-hard-negative-mining for improved prediction. The proposed models are lightweight and can be connected in an end-to-end manner during deployment to automatically identify each product object placed in a rack image. Extensive experiments using Grozi-32k and GP-180 data sets verify the effectiveness of the proposed model.

Keywords: retail stores, faster-RCNN, object localization, ResNet-18, triplet loss, data augmentation, product recognition

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3890 Bereavement Risk Assessment of Family Caregivers of Patients with Cancer: Relationship between Bereavement Risk and Post-Loss Psychological Distress

Authors: Tomohiro Uchida, Noriaki Satake, Toshimichi Nakaho, Akira Inoue, Hidemitsu Saito

Abstract:

In this study, we assessed the bereavement risk of family caregivers of patients with cancer. In the palliative care unit of Tohoku University Hospital, we conducted a family psychoeducation session to support the family caregivers of patients with cancer. A total of 50 participants (8 males and 42 females; mean age = 62.98 years, SD = 11.10) were assessed after the session for bereavement risk using the Japanese version of the Bereavement Risk Assessment Tool (BRAT-J). According to the BRAT-J scores, eight participants were considered to be having no known risk (Level 1), seventeen had minimal risk (Level 2), twenty had a low risk (Level 3), four had a moderate risk (Level 4), and one had a high risk (Level 5). Of these participants, seven participants had completed the follow-up postal survey that assessed their psychological distress (the Kessler Psychological Distress Scale: K6) to compare the bereavement risk. According to the K6 scores, three-fourth of the individuals, who were considered to be at Level 3 on the BRAT-J, scored higher than the cutoff point (>10) for the detection of depressive disorder. On the other hand, one-third of the individuals, who were considered to be at Level 2 on the BRAT-J, scored higher than the cutoff point. Therefore, it appears that the BRAT-J can predict the likelihood of difficulties or complications in bereaved family caregivers. This research was approved by the Ethics Committee of Tohoku University Graduate School of Medicine and Tohoku University Hospital.

Keywords: palliative care, family caregivers, bereavement risk, BRAT, post-loss psychological distress

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3889 Effect of Laser Ablation OTR Films on the Storability of Endive and Pak Choi by Baby Vegetables in Modified Atmosphere Condition

Authors: In-Lee Choi, Min Jae Jeong, Jun Pill Baek, Ho-Min Kang

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As the consumption trends of vegetables become different from the past, it is increased using vegetable more convenience such as fresh-cut vegetables, sprouts, baby vegetables rather than an existing hole piece of vegetables. Selected baby vegetables have various functional materials but they have short shelf life. This study was conducted to improve storability by using suitable laser ablation OTR (oxygen transmission rate) films. Baby vegetable of endive (Cichorium endivia L.) and pak choi (Brassica rapa chinensis) for this research, around 10 cm height, cultivated in glass greenhouse during 3 weeks. Harvested endive and pak choi were stored at 8 ℃ for 5 days and were packed by PP (Polypropylene) container and covered different types of laser ablation OTR film (DaeRyung Co., Ltd.) such as 1,300 cc, 10,000 cc, 20,000 cc, 40,000 cc /m2•day•atm, and control (perforated film) with heat sealing machine (SC200-IP, Kumkang, Korea). All the samples conducted 5 times replication. Statistical analysis was carried out using a Microsoft Excel 2010 program and results were expressed as standard deviations. The fresh weight loss rate of both baby vegetables were less than 0.3 % in treated films as maximum weight loss rate. On the other hands, control in the final storage day had around 3.0 % weight loss rate and it followed decreasing quantity. Endive had less 2.0 % carbon dioxide contents as maximum contents in 20,000 cc and 40,000 cc. Oxygen contents was maintained between 17 and 20 % in endive, 19 and 20 % in pak choi. Ethylene concentration of both vegetables maintained little lower contents in 20,000 cc treatments than others at final storage day without statistical significance. In the case of hardness, 40,000 cc film was shown little higher value at both baby vegetables without statistical significance. Visual quality was good at 10,000 cc and 20,000 cc in endive and pak choi, and off-flavor was not appeard any off-flavor in both vegetables. Chlorophyll (SPAD-502, Minolta, Japan) value of endive was shown as similar result with initial in all treatments except 20,000 cc as little lower. And chlorophyll value of pak choi decreased in all treatments compared with initial value but was not shown significantly difference each other. Color of leaves (CR-400, Minolta, Japan) changed significantly in 40,000 cc at endive. In an event of pak choi, all the treatments started yellowing by increasing hunter b value, among them control increased substantially. As above the result, 10,000 cc film was most reasonable packaging film for storing at endive and 20,000 cc at pak choi with good quality.

Keywords: carbon dioxide, shelf-life, visual quality, pak choi

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3888 The Study of Periodontal Health Status in Menopausal Women with Osteoporosis Referred to Rheumatology Clinics in Yazd and Healthy People

Authors: Mahboobe Daneshvar

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Introduction: Clinical studies on the effect of systemic conditions on periodontal diseases have shown that some systemic deficiencies may provide grounds for the onset of periodontal diseases. One of these systemic problems is osteoporosis, which may be a risk factor for the onset and exacerbation of periodontitis. This study tends to evaluate periodontal indices in osteoporotic menopausal women and compare them with healthy controls. Materials and Methods: In this case-control study, participants included 45-75-year-old menopausal women referred to rheumatology wards of the Khatamolanbia Clinic and Shahid Sadoughi Hospital in Yazd; Their bone density was determined by DEXA-scan and by imaging the femoral-lumbar bone. Thirty patients with osteoporosis and 30 subjects with normal BMD were selected. Then, informed consent was obtained for participation in the study. During the clinical examinations, tooth loss (TL), plaque index (PI), gingival recession, pocket probing depth (PPD), clinical attachment loss (CAL), and tooth mobility (TM) were measured to evaluate the periodontal status. These clinical examinations were performed to determine the periodontal status by catheter, mirror and probe. Results: During the evaluation, there was no significant difference in PPD, PI, TM, gingival recession, and CAL between case and control groups (P-value>0.05); that is, osteoporosis has no effect on the above factors. These periodontal factors are almost the same in both healthy and patient groups. In the case of missing teeth, the following results were obtained: the mean of missing teeth was 22.173% of the total teeth in the case group and 18.583% of the total teeth in the control group. In the study of the missing teeth in the case and control groups, there was a significant relationship between case and control groups (P-value = 0.025). Conclusion: In fact, since periodontal disease is multifactorial and microbial plaque is the main cause, osteoporosis is considered a predisposing factor in exacerbation or persistence of periodontal disease. In patients with osteoporosis, usually pathological fractures, hormonal changes, and aging lead to reduced physical activity and affect oral health, which leads to the manifestation of periodontal disease. But this disease increases tooth loss by changing the shape and structure of bone trabeculae and weakening them. Osteoporosis does not seem to be a deterministic factor in the incidence of periodontal disease, since it affects bone quality rather than bone quantity.

Keywords: plaque index, Osteoporosis, tooth mobility, periodontal packet

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3887 Estimation of Effective Mechanical Properties of Linear Elastic Materials with Voids Due to Volume and Surface Defects

Authors: Sergey A. Lurie, Yury O. Solyaev, Dmitry B. Volkov-Bogorodsky, Alexander V. Volkov

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The media with voids is considered and the method of the analytical estimation of the effective mechanical properties in the theory of elastic materials with voids is proposed. The variational model of the porous media is discussed, which is based on the model of the media with fields of conserved dislocations. It is shown that this model is fully consistent with the known model of the linear elastic materials with voids. In the present work, the generalized model of the porous media is proposed in which the specific surface properties are associated with the field of defects-pores in the volume of the deformed body. Unlike typical surface elasticity model, the strain energy density of the considered model includes the special part of the surface energy with the quadratic form of the free distortion tensor. In the result, the non-classical boundary conditions take modified form of the balance equations of volume and surface stresses. The analytical approach is proposed in the present work which allows to receive the simple enough engineering estimations for effective characteristics of the media with free dilatation. In particular, the effective flexural modulus and Poisson's ratio are determined for the problem of a beam pure bending. Here, the known voids elasticity solution was expanded on the generalized model with the surface effects. Received results allow us to compare the deformed state of the porous beam with the equivalent classic beam to introduce effective bending rigidity. Obtained analytical expressions for the effective properties depend on the thickness of the beam as a parameter. It is shown that the flexural modulus of the porous beam is decreased with an increasing of its thickness and the effective Poisson's ratio of the porous beams can take negative values for the certain values of the model parameters. On the other hand, the effective shear modulus is constant under variation of all values of the non-classical model parameters. Solutions received for a beam pure bending and the hydrostatic loading of the porous media are compared. It is shown that an analytical estimation for the bulk modulus of the porous material under hydrostatic compression gives an asymptotic value for the effective bulk modulus of the porous beam in the case of beam thickness increasing. Additionally, it is shown that the scale effects appear due to the surface properties of the porous media. Obtained results allow us to offer the procedure of an experimental identification of the non-classical parameters in the theory of the linear elastic materials with voids based on the bending tests for samples with different thickness. Finally, the problem of implementation of the Saint-Venant hypothesis for the transverse stresses in the porous beam are discussed. These stresses are different from zero in the solution of the voids elasticity theory, but satisfy the integral equilibrium equations. In this work, the exact value of the introduced surface parameter was found, which provides the vanishing of the transverse stresses on the free surfaces of a beam.

Keywords: effective properties, scale effects, surface defects, voids elasticity

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3886 The Relevance of Family Involvement in the Journey of Dementia Patients

Authors: Akankunda Veronicah Karuhanga

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Dementia is an age mental disorder that makes victims lose normal functionality that needs delicate attention. It has been technically defined as a clinical syndrome that presents a number of difficulties in speech and other cognitive functions that change someone’s behaviors and can also cause impairments in activities of daily living, not forgetting a range of neurological disorders that bring memory loss and cognitive impairment. Family members are the primary healthcare givers and therefore, the way how they handle the situation in its early stages determines future deterioration syndromes like total memory loss. Unfortunately, most family members are ignorant about this condition and in most cases, the patients are brought to our facilities when their condition was already mismanaged by family members and we thus cannot do much. For example, incontinence can be managed at early stages through potty training or toilet scheduling before resorting to 24/7 diapers which are also not good. Professional Elderly care should be understood and practiced as an extension of homes, not a dumping place for people considered “abnormal” on account of ignorance. Immediate relatives should therefore be sensitized concerning the normalcy of dementia in the context of old age so that they can be understanding and supportive of dementia patients rather than discriminating against them as present-day lepers. There is a need to skill home-based caregivers on how to handle dementia in its early stages. Unless this is done, many of our elderly homes shall be filled with patients who should have been treated and supported from their homes. This skilling of home-based caregivers is a vital intervention because until elderly care is appreciated as a human moral obligation, many transactional rehabilitation centers will crop up and this shall be one of the worst moral decadences of our times.

Keywords: dementia, family, Alzheimers, relevancy

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3885 Opportunities for Precision Feed in Apiculture

Authors: John Michael Russo

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Honeybees are important to our food system and continue to suffer from high rates of colony loss. Precision feed has brought many benefits to livestock cultivation and these should transfer to apiculture. However, apiculture has unique challenges. The objective of this research is to understand how principles of precision agriculture, applied to apiculture and feed specifically, might effectively improve state-of-the-art cultivation. The methodology surveys apicultural practice to build a model for assessment. First, a review of apicultural motivators is made. Feed method is then evaluated. Finally, precision feed methods are examined as accelerants with potential to advance the effectiveness of feed practice. Six important motivators emerge: colony loss, disease, climate change, site variance, operational costs, and competition. Feed practice itself is used to compensate for environmental variables. The research finds that the current state-of-the-art in apiculture feed focuses on critical challenges in the management of feed schedules which satisfy requirements of the bees, preserve potency, optimize environmental variables, and manage costs. Many of the challenges are most acute when feed is used to dispense medication. Technology such as RNA treatments have even more rigorous demands. Precision feed solutions focus on strategies which accommodate specific needs of individual livestock. A major component is data; they integrate precise data with methods that respond to individual needs. There is enormous opportunity for precision feed to improve apiculture through the integration of precision data with policies to translate data into optimized action in the apiary, particularly through automation.

Keywords: precision agriculture, precision feed, apiculture, honeybees

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3884 Effect of Bariatric Surgery on Metabolic Syndrome, Framingham Risk Score and Thyroid Function

Authors: Nuha Alamro

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Besides achieving of weight loss, Bariatric surgery (BS) shown metabolic improvement including reduction of cardiovascular disease, insulin resistance and diabetes. This study aimed to measure BS effects on Framingham Risk Score (FRS) and metabolic syndrome (MetS) among patients who underwent BS. Additionally, to determine the effect of BS on TSH among euthyroid obese patients. A Retrospective follow-up study was conducted in King Abdullah Medical City. A total of 160 participants who underwent BS and completed one year of follow ups. Medical history, biochemical, anthropometric, and hormonal parameters were evaluated at baseline and 3-12 months after BS. International Diabetes Federation (IDF) criteria were used to diagnose MetS pre and postoperative. The mean age of participants was 41.9 ± 10.6 with Body Mass Index (BMI) of 48.8 ± 7.3. After 3 months, Systolic, Diastolic blood pressure (SBP, DBP), glycated haemoglobin (HBA1C), Low-density lipoprotein (LDL), cholesterol, triglycerides and Thyroid stimulating hormone (TSH) were significantly decrease (P < 0.001). Significant decrease was seen in Mets, BMI, FRS, SBP, DBP, HBA1C, LDL, triglycerides, cholesterol, liver enzyme, with significant increase in high-density lipoprotein (HDL) level 12 months post-op (P < 0.001). After 1 year, the prevalence of MetS, DM, HTN, FRS were significantly decrease from 72.5%, 43.1%, 78.1%, 11.4 to 16.3%, 9.4%, 22.5% and 5.4, respectively. Besides achieving substantial weight loss, MetS resolution was linked to improvement in cardiovascular risk profile.

Keywords: bariatric surgery, cardiovascular disease, metabolic syndrome, thyroid stimulating hormone

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3883 Use of SUDOKU Design to Assess the Implications of the Block Size and Testing Order on Efficiency and Precision of Dulce De Leche Preference Estimation

Authors: Jéssica Ferreira Rodrigues, Júlio Silvio De Sousa Bueno Filho, Vanessa Rios De Souza, Ana Carla Marques Pinheiro

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This study aimed to evaluate the implications of the block size and testing order on efficiency and precision of preference estimation for Dulce de leche samples. Efficiency was defined as the inverse of the average variance of pairwise comparisons among treatments. Precision was defined as the inverse of the variance of treatment means (or effects) estimates. The experiment was originally designed to test 16 treatments as a series of 8 Sudoku 16x16 designs being 4 randomized independently and 4 others in the reverse order, to yield balance in testing order. Linear mixed models were assigned to the whole experiment with 112 testers and all their grades, as well as their partially balanced subgroups, namely: a) experiment with the four initial EU; b) experiment with EU 5 to 8; c) experiment with EU 9 to 12; and b) experiment with EU 13 to 16. To record responses we used a nine-point hedonic scale, it was assumed a mixed linear model analysis with random tester and treatments effects and with fixed test order effect. Analysis of a cumulative random effects probit link model was very similar, with essentially no different conclusions and for simplicity, we present the results using Gaussian assumption. R-CRAN library lme4 and its function lmer (Fit Linear Mixed-Effects Models) was used for the mixed models and libraries Bayesthresh (default Gaussian threshold function) and ordinal with the function clmm (Cumulative Link Mixed Model) was used to check Bayesian analysis of threshold models and cumulative link probit models. It was noted that the number of samples tested in the same session can influence the acceptance level, underestimating the acceptance. However, proving a large number of samples can help to improve the samples discrimination.

Keywords: acceptance, block size, mixed linear model, testing order, testing order

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3882 Numerical Erosion Investigation of Standalone Screen (Wire-Wrapped) Due to the Impact of Sand Particles Entrained in a Single-Phase Flow (Water Flow)

Authors: Ahmed Alghurabi, Mysara Mohyaldinn, Shiferaw Jufar, Obai Younis, Abdullah Abduljabbar

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Erosion modeling equations were typically acquired from regulated experimental trials for solid particles entrained in single-phase or multi-phase flows. Evidently, those equations were later employed to predict the erosion damage caused by the continuous impacts of solid particles entrained in streamflow. It is also well-known that the particle impact angle and velocity do not change drastically in gas-sand flow erosion prediction; hence an accurate prediction of erosion can be projected. On the contrary, high-density fluid flows, such as water flow, through complex geometries, such as sand screens, greatly affect the sand particles’ trajectories/tracks and consequently impact the erosion rate predictions. Particle tracking models and erosion equations are frequently applied simultaneously as a method to improve erosion visualization and estimation. In the present work, computational fluid dynamic (CFD)-based erosion modeling was performed using a commercially available software; ANSYS Fluent. The continuous phase (water flow) behavior was simulated using the realizable K-epsilon model, and the secondary phase (solid particles), having a 5% flow concentration, was tracked with the help of the discrete phase model (DPM). To accomplish a successful erosion modeling, three erosion equations from the literature were utilized and introduced to the ANSYS Fluent software to predict the screen wire-slot velocity surge and estimate the maximum erosion rates on the screen surface. Results of turbulent kinetic energy, turbulence intensity, dissipation rate, the total pressure on the screen, screen wall shear stress, and flow velocity vectors were presented and discussed. Moreover, the particle tracks and path-lines were also demonstrated based on their residence time, velocity magnitude, and flow turbulence. On one hand, results from the utilized erosion equations have shown similarities in screen erosion patterns, locations, and DPM concentrations. On the other hand, the model equations estimated slightly different values of maximum erosion rates of the wire-wrapped screen. This is solely based on the fact that the utilized erosion equations were developed with some assumptions that are controlled by the experimental lab conditions.

Keywords: CFD simulation, erosion rate prediction, material loss due to erosion, water-sand flow

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3881 Future Trends of Mechatronics Engineering in Pakistan

Authors: Aqeela Mir, Akhtar Nawaz Malik, Javaid Iqbal

Abstract:

The paper presents a survey based approach in order to observe the level of awareness regarding Mechatronics in society of Pakistan and the factors affecting the future development trend of Mechatronics in Pakistan. With the help of these surveys a new direction for making a Mathematical model for the future development trend of Mechatronics in Pakistan is also suggested.

Keywords: mechatronics society survey, future development trend of mechatronics in pakistan, probability estimation, mathematical model

Procedia PDF Downloads 489
3880 90-Day Strength Training Intervention Decreases Incidence of Sarcopenia: A Pre- and Posttest Pilot Study of Older Adults in a Skilled Nursing Facility

Authors: Donna-Marie Phyllis Lanton

Abstract:

Sarcopenia is a well-known geriatric syndrome characterized by the progressive and generalized loss of muscle quantity or quality. The incidence of sarcopenia increases with age and is associated with adverse outcomes such as the increased risk of falls, cognitive impairment, loss of independence, diminished quality of life, increased health costs, need for care in a skilled nursing facility, and increased mortality. Physical activity, including resistance training, is the most prevalent recommendation for treating and preventing sarcopenia. Residents (N = 23) of a skilled nursing facility in East Orlando, Florida, participated in a 90-day strength training program designed using the PARIHS framework to improve measures of muscle mass, muscle strength, physical performance, and quality of life. Residents engaged in both resistance and balance exercises for 1 hour two times a week. Baseline data were collected and compared to data at Days 30, 60, and 90. T tests indicated significant gains on all measures from baseline to 90 days: muscle mass increased by 1.2 (t[22] = 2.85, p = .009), grip strength increased by 4.02 (t[22] = 8.15, p < .001), balance increased by 2.13 (t[22] = 18.64, p < .001), gait speed increased by 1.83 (t[22] = 17.84, p < .001), chair speed increased 1.87 (t[22] = 16.36, p < .001), and quality of life score increased by 17.5 (t[22] = 19.26, p < .001). For residents with sarcopenia in skilled nursing facilities, a 90-day strength training program with resistance and balance exercises may provide an option for decreasing the incidence of sarcopenia among that population

Keywords: muscle mass, muscle strength, older adults, PARIHS framework

Procedia PDF Downloads 73
3879 Exploring the Applications of Neural Networks in the Adaptive Learning Environment

Authors: Baladitya Swaika, Rahul Khatry

Abstract:

Computer Adaptive Tests (CATs) is one of the most efficient ways for testing the cognitive abilities of students. CATs are based on Item Response Theory (IRT) which is based on item selection and ability estimation using statistical methods of maximum information selection/selection from posterior and maximum-likelihood (ML)/maximum a posteriori (MAP) estimators respectively. This study aims at combining both classical and Bayesian approaches to IRT to create a dataset which is then fed to a neural network which automates the process of ability estimation and then comparing it to traditional CAT models designed using IRT. This study uses python as the base coding language, pymc for statistical modelling of the IRT and scikit-learn for neural network implementations. On creation of the model and on comparison, it is found that the Neural Network based model performs 7-10% worse than the IRT model for score estimations. Although performing poorly, compared to the IRT model, the neural network model can be beneficially used in back-ends for reducing time complexity as the IRT model would have to re-calculate the ability every-time it gets a request whereas the prediction from a neural network could be done in a single step for an existing trained Regressor. This study also proposes a new kind of framework whereby the neural network model could be used to incorporate feature sets, other than the normal IRT feature set and use a neural network’s capacity of learning unknown functions to give rise to better CAT models. Categorical features like test type, etc. could be learnt and incorporated in IRT functions with the help of techniques like logistic regression and can be used to learn functions and expressed as models which may not be trivial to be expressed via equations. This kind of a framework, when implemented would be highly advantageous in psychometrics and cognitive assessments. This study gives a brief overview as to how neural networks can be used in adaptive testing, not only by reducing time-complexity but also by being able to incorporate newer and better datasets which would eventually lead to higher quality testing.

Keywords: computer adaptive tests, item response theory, machine learning, neural networks

Procedia PDF Downloads 160
3878 The Effects of Applying Wash and Green-A Syrups as Substitution of Sugar on Dough and Cake Properties

Authors: Banafsheh Aghamohammadi, Masoud Honarvar, Babak Ghiassi Tarzi

Abstract:

Usage of different components has been considered to improve the quality and nutritional properties of cakes in recent years. The effects of applying some sweeteners, instead of sugar, have been evaluated in cakes and many bread formulas up to now; but there has not been any research about the usage of by-products of sugar factories such as Wash and Green-A Syrups in cake formulas. In this research, the effects of substituting 25%, 50%, 75% and 100% of sugar with Wash and Green-A Syrups on some dough and cake properties, such as pH, viscosity, density, volume, weight loss, moisture, water activity, texture, staling, color and sensory evaluations, are studied. The results of these experiments showed that the pH values were not significantly different among any of the all cake batters and also most of the cake samples. Although differences among viscosity and specific gravity of all treatments were both significant and insignificant, these two parameters resulted in higher volume in all samples than the blank one. The differences in weight loss, moisture content and water activity of samples were insignificant. Evaluating of texture showed that the softness of most of samples is increased and the staling is decreased. Crumb color and sensory evaluations of samples were also affected by the replacement of sucrose with Wash and Green-A Syrups. According to the results, we can increase the shelf life and improve the quality and nutritional values of cake by using these kinds of syrups in the formulation.

Keywords: cake, green-A syrup, quality tests, sensory evaluation, wash syrup

Procedia PDF Downloads 156
3877 Tuning Nanomechanical Properties of Stimuli-Responsive Hydrogel Nanocomposite Thin Films for Biomedical Applications

Authors: Mallikarjunachari Gangapuram

Abstract:

The design of stimuli-responsive hydrogel nanocomposite thin films is gaining significant attention in these days due to its wide variety of applications. Soft microrobots, drug delivery, biosensors, regenerative medicine, bacterial adhesion, energy storage and wound dressing are few advanced applications in different fields. In this research work, the nanomechanical properties of composite thin films of 20 microns were tuned by applying homogeneous external DC, and AC magnetic fields of magnitudes 0.05 T and 0.1 T. Polyvinyl alcohol (PVA) used as a matrix material and elliptical hematite nanoparticles (ratio of the length of the major axis to the length of the minor axis is 140.59 ± 1.072 nm/52.84 ± 1.072 nm) used as filler materials to prepare the nanocomposite thin films. Both quasi-static nanoindentation, Nano Dynamic Mechanical Analysis (Nano-DMA) tests were performed to characterize the viscoelastic properties of PVA, PVA+Hematite (0.1% wt, 2% wt and 4% wt) nanocomposites. Different properties such as storage modulus, loss modulus, hardness, and Er/H were carefully analyzed. The increase in storage modulus, hardness, Er/H and a decrease in loss modulus were observed with increasing concentration and DC magnetic field followed by AC magnetic field. Contact angle and ATR-FTIR experiments were conducted to understand the molecular mechanisms such as hydrogen bond formation, crosslinking density, and particle-particle interactions. This systematic study is helpful in design and modeling of magnetic responsive hydrogel nanocomposite thin films for biomedical applications.

Keywords: hematite, hydrogel, nanoindentation, nano-DMA

Procedia PDF Downloads 176
3876 Design and Performance Comparison of Metamaterial Based Antenna for 4G/5G Mobile Devices

Authors: Jalal Khan, Daniyal Ali Sehrai, Shakeel Ahmad

Abstract:

This paper presents the design and performance evaluation of multiband metamaterial based antenna operating in the 3.6 GHz (4G), 14.33 GHz, and 28.86 GHz (5G) frequency bands, for future mobile and handheld devices. The radiating element of the proposed design is made up of a conductive material supported by a 1.524 mm thicker Rogers-4003 substrate, having a relative dielectric constant and loss tangent of 3.55 and 0.0027, respectively. The substrate is backed by truncated ground plane. The future mobile communication system is based on higher frequencies, which are highly affected by the atmospheric conditions. Therefore, to overcome the path loss problem, essential enhancements and improvements must be made in the overall performance of the antenna. The traditional ground plane does not provide the in-phase reflection and surface wave suppression due to which side and back lobes are produced. This will affect the antenna performance in terms of gain and efficiency. To enhance the overall performance of the antenna, a metamaterial acting as a high impedance surface (HIS) is used as a reflector in the proposed design. The simulated gain of the metamaterial based antenna is enhanced from {2.76-6.47, 4.83-6.71 and 7.52-7.73} dB at 3.6, 14.33 and 28.89 GHz, respectively relative to the gain of the antenna backed by a traditional ground plane. The proposed antenna radiated efficiently with a radiated efficiency (>85 %) in all the three frequency bands with and without metamaterial surface. The total volume of the antenna is (L x W x h=45 x 40 x 1.524) mm3. The antenna can be potentially used for wireless handheld devices and mobile terminal. All the simulations have been performed using the Computer Simulation Technology (CST) software.

Keywords: CST MWS, fourth generation/fifth generation, 4G/5G, high gain, multiband, metamaterial

Procedia PDF Downloads 148
3875 Chemical Fingerprinting of Complex Samples With the Aid of Parallel Outlet Flow Chromatography

Authors: Xavier A. Conlan

Abstract:

Speed of analysis is a significant limitation to current high-performance liquid chromatography/mass spectrometry (HPLC/MS) and ultra-high-pressure liquid chromatography (UHPLC)/MS systems both of which are used in many forensic investigations. The flow rate limitations of MS detection require a compromise in the chromatographic flow rate, which in turn reduces throughput, and when using modern columns, a reduction in separation efficiency. Commonly, this restriction is combated through the post-column splitting of flow prior to entry into the mass spectrometer. However, this results in a loss of sensitivity and a loss in efficiency due to the post-extra column dead volume. A new chromatographic column format known as 'parallel segmented flow' involves the splitting of eluent flow within the column outlet end fitting, and in this study we present its application in order to interrogate the provenience of methamphetamine samples with mass spectrometry detection. Using parallel segmented flow, column flow rates as high as 3 mL/min were employed in the analysis of amino acids without post-column splitting to the mass spectrometer. Furthermore, when parallel segmented flow chromatography columns were employed, the sensitivity was more than twice that of conventional systems with post-column splitting when the same volume of mobile phase was passed through the detector. These finding suggest that this type of column technology will particularly enhance the capabilities of modern LC/MS enabling both high-throughput and sensitive mass spectral detection.

Keywords: chromatography, mass spectrometry methamphetamine, parallel segmented outlet flow column, forensic sciences

Procedia PDF Downloads 471
3874 Systematic Literature Review of Therapeutic Use of Autonomous Sensory Meridian Response (ASMR) and Short-Term ASMR Auditory Training Trial

Authors: Christine H. Cubelo

Abstract:

This study consists of 2-parts: a systematic review of current publications on the therapeutic use of autonomous sensory meridian response (ASMR) and a within-subjects auditory training trial using ASMR videos. The main intent is to explore ASMR as potentially therapeutically beneficial for those with atypical sensory processing. Many hearing-related disorders and mood or anxiety symptoms overlap with symptoms of sensory processing issues. For this reason, inclusion and exclusion criteria of the systematic review were generated in an effort to produce optimal search outcomes and avoid overly confined criteria that would limit yielded results. Criteria for inclusion in the review for Part 1 are (1) adult participants diagnosed with hearing loss or atypical sensory processing, (2) inclusion of measures related to ASMR as a treatment method, and (3) published between 2000 and 2022. A total of 1,088 publications were found in the preliminary search, and a total of 13 articles met the inclusion criteria. A total of 14 participants completed the trial and post-trial questionnaire. Of all responses, 64.29% agreed that the duration of auditory training sessions was reasonable. In addition, 71.43% agreed that the training improved their perception of music. Lastly, 64.29% agreed that the training improved their perception of a primary talker when there are other talkers or background noises present.

Keywords: autonomous sensory meridian response, auditory training, atypical sensory processing, hearing loss, hearing aids

Procedia PDF Downloads 43
3873 NANCY: Combining Adversarial Networks with Cycle-Consistency for Robust Multi-Modal Image Registration

Authors: Mirjana Ruppel, Rajendra Persad, Amit Bahl, Sanja Dogramadzi, Chris Melhuish, Lyndon Smith

Abstract:

Multimodal image registration is a profoundly complex task which is why deep learning has been used widely to address it in recent years. However, two main challenges remain: Firstly, the lack of ground truth data calls for an unsupervised learning approach, which leads to the second challenge of defining a feasible loss function that can compare two images of different modalities to judge their level of alignment. To avoid this issue altogether we implement a generative adversarial network consisting of two registration networks GAB, GBA and two discrimination networks DA, DB connected by spatial transformation layers. GAB learns to generate a deformation field which registers an image of the modality B to an image of the modality A. To do that, it uses the feedback of the discriminator DB which is learning to judge the quality of alignment of the registered image B. GBA and DA learn a mapping from modality A to modality B. Additionally, a cycle-consistency loss is implemented. For this, both registration networks are employed twice, therefore resulting in images ˆA, ˆB which were registered to ˜B, ˜A which were registered to the initial image pair A, B. Thus the resulting and initial images of the same modality can be easily compared. A dataset of liver CT and MRI was used to evaluate the quality of our approach and to compare it against learning and non-learning based registration algorithms. Our approach leads to dice scores of up to 0.80 ± 0.01 and is therefore comparable to and slightly more successful than algorithms like SimpleElastix and VoxelMorph.

Keywords: cycle consistency, deformable multimodal image registration, deep learning, GAN

Procedia PDF Downloads 107
3872 Evaluation of Raw Diatomaceous Earth and Plant Powders in the Control of Callosobruchus subinnotatus (Pic.) on Stored Bambara Groundnut (Vigna subterranea (L.) (Verdc.) Seeds

Authors: Ibrahim Nasiru Dole, Audu Abdullahi, Dike Michiel Chidozie, Lawal Mansur

Abstract:

Bambara groundnut is an important grain legume and the seeds in storage suffer infestation by Callosobruchus subinnotatus. Laboratory study was conducted to evaluate the efficacy of raw diatomaceous earth (RDE) and plant powders (Jatropha curcas (L.), Eucalyptus camaldulensis (Dehnh.) and Melia azedarach (L.) against C. subinnotatus infesting stored bambara groundnut seeds. Rearing of the insects and the experiments were conducted in Agricultural Biology Laboratory of the Usmanu Danfodiyo University, Sokoto - Nigeria under ambient conditions (29-33oC and a relative humidity of 44-56%). Four treatments at three levels: RDE at 0.5, 1.0 and 1.5 g while plant powders at 0.5, 1.0 and 2.0 g, standard/check (2.0 g of Actellic dust), and a control. These were separately admixed with 100 g of sterilized seeds in glass jars. Each jar was later infested with thirty, 1-2-days old C. subinnotatus of mixed sexes. Adult mortality was assessed 24, 48, 72 and 96 hours, F1 and F2 progenies, seed damage, weight loss and viability were also assessed after 90 days. Eighty-nine (89%) percent adult mortality was recorded in the highest dose of RDE after 96 hours of exposure. These treatments significantly (P < 0.05) suppressed F1 and F2 progenies emergence in relation to the control. The control suffered significantly (P < 0.05) higher seed damage (51.0 %) and weight loss (40.8%) thereby recording lower seed germination. Therefore, RDE and plant powders could be used against C. subinnotatus on stored bambara groundnut seeds.

Keywords: bambara, callosobruchus subinnotatus, plant powders, raw diatomaceous earth,

Procedia PDF Downloads 403
3871 Direct Cost of Anesthesia in Traumatic Patients with Massive Bleeding: A Prospective Micro-Costing Study

Authors: Asamaporn Puetpaiboon, Sunisa Chatmongkolchart, Nalinee Kovitwanawong, Osaree Akaraborworn

Abstract:

Traumatic patients with massive bleeding require intensive resuscitation. The actual cost of anesthesia per case has never been clarified, so our study aimed to quantify the direct cost, and cost-to-charge ratio of anesthetic care in traumatic patients with intraoperative massive bleeding. This study was a prospective, observational, cost analysis study, conducted in Prince of Songkla University hospital, Thailand, with traumatic patients, of any mechanisms being recruited. Massive bleeding was defined as estimated blood loss of at least one blood volume in 24 hours, or a half of blood volume in 3 hours. The cost components were identified by the micro-costing method, and valued by the bottom-up approach. The direct cost was divided into 4 categories: the labor cost, the capital cost, the material cost and the cost of drugs. From September 2017 to August 2018, 10 patients with multiple injuries were included. Seven patients had motorcycle accidents, two patients fell from a height and another one was in a minibus accident. Two patients died on the operating table, and another two died within 48 hours. The median Sequential Organ Failure Assessment (SOFA) score was 8. The median intraoperative blood loss was 3,500 ml. The median direct cost, per case, was 250 United States Dollars (2017 exchange rate), and the cost-to-charge ratio was 0.53. In summary, the direct cost was nearly half of the hospital charge, for these traumatic patients with massive bleeding. However, our study did not analyze the indirect cost.

Keywords: cost, cost-to-charge ratio, micro-costing, trauma

Procedia PDF Downloads 130
3870 High Temperature Oxidation of Additively Manufactured Silicon Carbide/Carbon Fiber Nanocomposites

Authors: Saja M. Nabat Al-Ajrash, Charles Browning, Rose Eckerle, Li Cao, Robyn L. Bradford, Donald Klosterman

Abstract:

An additive manufacturing process and subsequent pyrolysis cycle were used to fabricate SiC matrix/carbon fiber hybrid composites. The matrix was fabricated using a mixture of preceramic polymer and acrylate monomers, while polyacrylonitrile (PAN) precursor was used to fabricate fibers via electrospinning. The precursor matrix and reinforcing fibers at 0, 2, 5, or 10 wt% were printed using digital light processing, and both were simultaneously pyrolyzed to yield the final ceramic matrix composite structure. After pyrolysis, XRD and SEAD analysis proved the existence of SiC nanocrystals and turbostratic carbon structure in the matrix, while the reinforcement phase was shown to have a turbostratic carbon structure similar to commercial carbon fibers. Thermogravimetric analysis (TGA) in the air up to 1400 °C was used to evaluate the oxidation resistance of this material. TGA results showed some weight loss due to oxidation of SiC and/or carbon up to about 900 °C, followed by weight gain to about 1200 °C due to the formation of a protective SiO2 layer. Although increasing carbon fiber content negatively impacted the total mass loss for the first heating cycle, exposure of the composite to second-run air revealed negligible weight chance. This is explained by SiO2 layer formation, which acts as a protective film that prevents oxygen diffusion. Oxidation of SiC and the formation of a glassy layer has been proven to protect the sample from further oxidation, as well as provide healing of surface cracks and defects, as revealed by SEM analysis.

Keywords: silicon carbide, carbon fibers, additive manufacturing, composite

Procedia PDF Downloads 56
3869 Generalization of Tau Approximant and Error Estimate of Integral Form of Tau Methods for Some Class of Ordinary Differential Equations

Authors: A. I. Ma’ali, R. B. Adeniyi, A. Y. Badeggi, U. Mohammed

Abstract:

An error estimation of the integrated formulation of the Lanczos tau method for some class of ordinary differential equations was reported. This paper is concern with the generalization of tau approximants and their corresponding error estimates for some class of ordinary differential equations (ODEs) characterized by m + s =3 (i.e for m =1, s=2; m=2, s=1; and m=3, s=0) where m and s are the order of differential equations and number of overdetermination, respectively. The general result obtained were validated with some numerical examples.

Keywords: approximant, error estimate, tau method, overdetermination

Procedia PDF Downloads 584
3868 Using Environmental Life Cycle Assessment to Design Sustainable Packaging

Authors: Timothy Francis Grant

Abstract:

There are conflicting purposes at play with the design of sustainable packaging which include material reduction, recycling compatibility, use of secondary content and performance of the package in protecting and delivering the product. Life Cycle Assessment (LCA) is able to evaluate these different strategies against environmental metrics such as climate change, land and water use and marine litter pollution. However, LCA has traditionally been too time consuming and expensive to be used effectively in packaging design process. To make LCA practical for packaging technologist and designers a simplified tool is needed to make LCA possible for non-environmental specialists. The Packaging Quick Evaluation Tool (PIQET) is a web-based solution for undertaking LCA of new and existing packaging designs considering the global supply chain and impacts from cradle to grave. PIQET is based on a pre-calculated LCA database covering the materials and processes involved in the packaging lifecycle from cradle to grave. This includes both virgin materials and recycled content, conversion of materials into packaging, and the transportation of packaging to the product filling. In addition, PIQET assesses the impacts once the package is filled looking at storage, transport and product loss through the supply chain. When applied to consumer packaging light weight packages which are note recyclable have lower impacts than more recyclable packages which have a higher mass. Its also apparent that for many products the impacts of product failure and product loss are more important environmentally compared to packaging material efficiency.

Keywords: Climate change, Life Cycle Assessment, Marine litter, Packaging sustainability

Procedia PDF Downloads 109