Search results for: maximum period nonlinear CA
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10390

Search results for: maximum period nonlinear CA

2950 The Impact of the Board of Directors’ Characteristics on Tax Aggressiveness in USA Companies

Authors: jihen ayadi sellami

Abstract:

The rapid evolution of the global financial landscape has led to increased attention to corporate tax policies and the need to understand the factors that influence their tax behavior. In order to mitigate any residual loss for shareholders resulting from tax aggressiveness and resolve the agency problem, appropriate systems that separate the function of management from that of controlling are needed. In this context of growing concerns to limit aggressive corporate taxation practices through governance, this study discusses. Its aims is to examine the influence of six key characteristics of the board of directors (board size, diligence, CEO duality, presence of audit committees, gender diversity and independence of directors), given a governance mechanism, on the tax decisions of non-financial corporations in the United State. In fact, using a sample of 90 non-financial US firms from S&P 500 over a period of 4 years going from 2014 to 2017, the results based on a multivariate linear regression highlight significant associations between these characteristics and corporate tax policy. Notably, larger board, gender diversity, diligence and increased director independence appear to play an important role in reducing aggressive taxation. While duality has a positive and significant correlation with tax aggressiveness, that can be explained by the fact that the manager did properly exploit his specific position within the company. These findings contribute to a deeper understanding of how board characteristics can influence corporate tax management, providing avenues for more effective corporate governance and more responsible tax decision-making

Keywords: tax aggressiveness, board of directors, board size, CEO duality, audit committees, gender diversity, director independence, diligence, corporate governance, united states

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2949 Constructions of Teaching English as a Second Language Teacher Trainees’ Professional Identities

Authors: K. S. Kan

Abstract:

The main purpose of this paper is to deepen the current understanding of how a Teaching English as a Second Language (TESL) teacher trainee self is constructed. The present aim of Malaysian TESL teacher education is to train teacher trainees with established English Language Teaching methodologies of the four main language skills (listening, reading, writing and speaking) apart from building them up holistically. Therefore, it is crucial to learn more of the ways on how these teacher trainees construct their professional selves during their undergraduate years. The participants come from a class of 17 Semester 6 TESL students who had undergone a 3-month’s practicum practice during their fifth semester and going for their final 3 month’s practicum period from July 2018 onwards. Findings from a survey, interviews with the participants and lecturers, documentations such as the participants’ practicum record-books would be consolidated with the supervisory notes and comments. The findings suggest that these teacher trainees negotiate their identities and emotions that react with the socio-cultural factors. Periodical reflections on the teacher trainees’ practicum practices influence transformation.The findings will be further aligned to the courses that these teacher trainees have to take in order to equip them as future second language practitioners. It is hoped that the findings will be able to fill the gap from the teacher trainees’ perspectives on identity construction dealing. This study is much more significant now, in view of the new English Language Curriculum for Primary School (widely known as KSSR, its Malay acronym) which had been introduced and implemented in Malaysian primary schools recently. This research will benefit second language practitioners who is in the language education field, as well as, TESL undergraduates, on the knowledge of how teacher trainees respond to and negotiate their professional teaching identities as future second language educators.

Keywords: construction of selves, professional identities, second language, TEST teacher trainees

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2948 Effects of Bariatric Surgery on Preventing the Progression of Diabetic Retinopathy

Authors: Yunzi Chen, James Laybourne, Sarah Steven, Peter Carey, David Steel, Maria Sandinha

Abstract:

Introduction: Bariatric surgery is popular with the rising incidence of obesity. Its well-known benefits include significant and rapid glycaemic control. However, cases of paradoxical worsening in diabetic retinopathy (DR) despite improved glycaemic control have been reported. Purpose: clarification on the evolution of diabetic retinopathy after bariatric surgery. Method: retrospective study of 40 patients with Type 2 diabetes who underwent bariatric surgery in a UK specialist bariatric unit between 2009 and 2011. Pre-operative and post-operative visual acuity (VA), weight, HbA1c and annual DRSS screening results were analysed. Median follow up was 50 months. Results: No significant change in VA was found during the post-operative period. 85% of patients improved HbA1c post-operatively of which 53% achieved non-diabetic HbA1c of <6.1% - despite this, 2 patients developed new DR. First post-operative screening showed 80% of patients experienced no change, 8% improved but 13% of patients developed new DR (1 case with sight-threatening maculopathy). 80% of these cases persisted up to 24 months. The proportion of patients developing new or worse DR fluctuated over time, peaking at the 3rd annual screening with 26% (15% regressed, 56% stable). The probability of developing new or worse DR postoperatively was significantly associated with a high pre-operative HbA1c (>8%) and male gender. Conclusions: bariatric surgery does not guarantee long-term improvement or prevention of DR. Asymptomatic changes in DR occurred up to 5 years postoperatively. We therefore consider it prudent to continue screening in this cohort of patients.

Keywords: bariatric surgery, diabetic retinopathy, obesity, type 2 diabetes mellitus

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2947 A Variational Reformulation for the Thermomechanically Coupled Behavior of Shape Memory Alloys

Authors: Elisa Boatti, Ulisse Stefanelli, Alessandro Reali, Ferdinando Auricchio

Abstract:

Thanks to their unusual properties, shape memory alloys (SMAs) are good candidates for advanced applications in a wide range of engineering fields, such as automotive, robotics, civil, biomedical, aerospace. In the last decades, the ever-growing interest for such materials has boosted several research studies aimed at modeling their complex nonlinear behavior in an effective and robust way. Since the constitutive response of SMAs is strongly thermomechanically coupled, the investigation of the non-isothermal evolution of the material must be taken into consideration. The present study considers an existing three-dimensional phenomenological model for SMAs, able to reproduce the main SMA properties while maintaining a simple user-friendly structure, and proposes a variational reformulation of the full non-isothermal version of the model. While the considered model has been thoroughly assessed in an isothermal setting, the proposed formulation allows to take into account the full nonisothermal problem. In particular, the reformulation is inspired to the GENERIC (General Equations for Non-Equilibrium Reversible-Irreversible Coupling) formalism, and is based on a generalized gradient flow of the total entropy, related to thermal and mechanical variables. Such phrasing of the model is new and allows for a discussion of the model from both a theoretical and a numerical point of view. Moreover, it directly implies the dissipativity of the flow. A semi-implicit time-discrete scheme is also presented for the fully coupled thermomechanical system, and is proven unconditionally stable and convergent. The correspondent algorithm is then implemented, under a space-homogeneous temperature field assumption, and tested under different conditions. The core of the algorithm is composed of a mechanical subproblem and a thermal subproblem. The iterative scheme is solved by a generalized Newton method. Numerous uniaxial and biaxial tests are reported to assess the performance of the model and algorithm, including variable imposed strain, strain rate, heat exchange properties, and external temperature. In particular, the heat exchange with the environment is the only source of rate-dependency in the model. The reported curves clearly display the interdependence between phase transformation strain and material temperature. The full thermomechanical coupling allows to reproduce the exothermic and endothermic effects during respectively forward and backward phase transformation. The numerical tests have thus demonstrated that the model can appropriately reproduce the coupled SMA behavior in different loading conditions and rates. Moreover, the algorithm has proved effective and robust. Further developments are being considered, such as the extension of the formulation to the finite-strain setting and the study of the boundary value problem.

Keywords: generalized gradient flow, GENERIC formalism, shape memory alloys, thermomechanical coupling

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2946 An Adaptable Semi-Numerical Anisotropic Hyperelastic Model for the Simulation of High Pressure Forming

Authors: Daniel Tscharnuter, Eliza Truszkiewicz, Gerald Pinter

Abstract:

High-quality surfaces of plastic parts can be achieved in a very cost-effective manner using in-mold processes, where e.g. scratch resistant or high gloss polymer films are pre-formed and subsequently receive their support structure by injection molding. The pre-forming may be done by high-pressure forming. In this process, a polymer sheet is heated and subsequently formed into the mold by pressurized air. Due to the heat transfer to the cooled mold the polymer temperature drops below its glass transition temperature. This ensures that the deformed microstructure is retained after depressurizing, giving the sheet its final formed shape. The development of a forming process relies heavily on the experience of engineers and trial-and-error procedures. Repeated mold design and testing cycles are however both time- and cost-intensive. It is, therefore, desirable to study the process using reliable computer simulations. Through simulations, the construction of the mold and the effect of various process parameters, e.g. temperature levels, non-uniform heating or timing and magnitude of pressure, on the deformation of the polymer sheet can be analyzed. Detailed knowledge of the deformation is particularly important in the forming of polymer films with integrated electro-optical functions. Care must be taken in the placement of devices, sensors and electrical and optical paths, which are far more sensitive to deformation than the polymers. Reliable numerical prediction of the deformation of the polymer sheets requires sophisticated material models. Polymer films are often either transversely isotropic or orthotropic due to molecular orientations induced during manufacturing. The anisotropic behavior affects the resulting strain field in the deformed film. For example, parts of the same shape but different strain fields may be created by varying the orientation of the film with respect to the mold. The numerical simulation of the high-pressure forming of such films thus requires material models that can capture the nonlinear anisotropic mechanical behavior. There are numerous commercial polymer grades for the engineers to choose from when developing a new part. The effort required for comprehensive material characterization may be prohibitive, especially when several materials are candidates for a specific application. We, therefore, propose a class of models for compressible hyperelasticity, which may be determined from basic experimental data and which can capture key features of the mechanical response. Invariant-based hyperelastic models with a reduced number of invariants are formulated in a semi-numerical way, such that the models are determined from a single uniaxial tensile tests for isotropic materials, or two tensile tests in the principal directions for transversely isotropic or orthotropic materials. The simulation of the high pressure forming of an orthotropic polymer film is finally done using an orthotropic formulation of the hyperelastic model.

Keywords: hyperelastic, anisotropic, polymer film, thermoforming

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2945 Effects of Exhaust Gas Emitted by the Fleet on Public Health in the Region of Annaba (Algeria): Ecotoxicological Test on Durum Wheat (Triticum durum Desf.)

Authors: Aouissi Nora, Meksem Leila

Abstract:

This work focused on the study of air pollution generated by the transport sector in the region of Annaba. Our study is based on two parts: the first one concerns an epidemiological investigation in the area of Annaba situated in the east Algerian coast, which deals with the development of the fleet and its impact on public health. To get a more precise idea of the impact of road traffic on public health, we consulted the computing center office of the National Social Insurance Fund. The information we were given by this office refers to the number of reported asthma and heart disease after medical examination during the period 2006-2010. The second part was devoted to the study of the toxicity of exhaust gases on some physical and biochemical parameters of durum wheat (Triticum durum Desf.). After germination and three-leaf stage, the pots are placed in a box of volume (0,096 m3) having an input which is linked directly to the exhaust pipe of a truck, and an outlet to prevent asphyxiation plant. The experience deals with 30 pots: 10 pots are exposed for 5 minutes to exhaust smoke; the other 10 are exposed for 15 minutes, and the remaining 10 for 30 minutes. The epidemiological study shows that the levels of pollutants emitted by the fleet are responsible for the increase of people respiratory and cardiovascular diseases. As for biochemical analyses of vegetation, they clearly show the toxicity of pollutants emitted by the exhaust gases, with an increase in total protein, proline and stimulation of detoxification enzyme (catalase).

Keywords: air pollution, toxicity, epidemiology, biochemistry

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2944 Early Childhood Care and Education in the North-West of Nigeria: Trends and Challenges

Authors: Muhammad Adamu Kwankwaso

Abstract:

Early childhood is a critical period of rapid physical, cognitive and psycho-social development of a child. The quality of care and Education which a child receives at this crucial age will determine to a great extent the level of his/her physical and cognitive development in the future. In Nigeria, Early Childhood Care and Education (ECCE) is a fundamental aspect or form of Education for children between the age of 3-6. It was started after independence as pre-primary Education or early child development as contained in the 1977 National Policy on Education. The trends towards ECCE in Nigeria and the northwestern part of the country in particular keep up changing as in the case of other part of the world. The current trends are now towards expansions, inclusiveness, redefinition, early literacy, increased government participation and the unprecedented societal response and awareness towards the Education of the younger children. While all hands are on deck to ensure successful implementation of the ECCE programme, it is unfortunate that, ECCE is facing some challenges. This paper therefore, examines the trends in Early Childhood Care and Education and the major challenges in the north west of Nigeria. Some of the major challenges include, inadequate trained ECCE teachers, lack of unified curriculum, teacher pupil’s ratio, and the medium of instructions and inadequate infrastructural and teaching facilities respectively. To improve the situation the paper offered the following recommendations; establishment of more ECCE classes, enforcement for the use of mothers’ tongue or the languages of the immediate community as a medium of instructions, and adequate provision of infrastructural facilities and the unified curriculum across the northwestern States of Nigeria.

Keywords: early childhood care, education, trends, challenges

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2943 The Effectiveness of Sexual Cognitive Behavioral Therapy on Strategic Thinking and Communication Patterns of Couples in Colostomy Patients

Authors: Alireza Monzavi Chaleshtari, Mahnaz Aliakbari Dehkordi, Seyedeh Somayeh Amiri, Mozhgan Shakhseniaei, Amin Asadi Hieh

Abstract:

The purpose of this research was to determine the effectiveness of sexual cognitive behavioral therapy on strategic thinking and communication patterns of couples in colostomy patients. In this study, experimental research was conducted with a pre-test and post-test design with a control group and a follow-up period. The statistical population studied were married female colostomy patients referring to the Iranian Ostomy Association. 30 qualified people were selected by voluntary sampling and randomly divided into two experimental and control groups (15 people in each group). Both groups responded to Goleman's strategic thinking (2007) and the communication patterns of Christensen and Sulawai questionnaires (1984). The results of covariance analysis showed that sexual cognitive behavioral therapy has an effect on improving strategic thinking. Based on the results of this test, sexual cognitive behavioral therapy is effective in improving the strategic thinking of colostomy patients until the follow-up stage. Also, sexual cognitive behavioral therapy has an effect on improving the communication patterns of couples in colostomy patients. Based on the results of this test, sexual cognitive behavioral therapy is effective in improving communication patterns of couples in patients with colostomy until the follow-up stage. Based on the results of this research, sexual cognitive behavioral therapy can be used to improve strategic thinking and communication patterns of couples of colostomy patients.

Keywords: sexual cognitive behavioral therapy, strategic thinking, communication patterns of couples, colostomy

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2942 Dirty Martini vs Martini: The Contrasting Duality Between Big Bang and BTS Public Image and Their Latest MVs Analysis

Authors: Patricia Portugal Marques de Carvalho Lourenco

Abstract:

Big Bang is like a dirty martini embroiled in a stew of personal individual scandals that have rocked the group’s image and perception, from G-Dragon’s and T.O.P. marijuana episodes in 2011 and 2016, respectively, to Daesung’s building illicit entertainment activities in 2018to the Burning Sun shebang that led to the Titanic sink of Big Bang’s youngest member Seungri in 2019 and the positive sentiment migration to the antithetical side. BTS, on the other hand, are like a martini, clear, clean, attracting as many crowds to their performances and online content as the Pope attracts believers to Sunday Mass in the Vatican, as exemplified by their latest MVs. Big Bang’s 2022 Still Life achieved 16.4 million views on Youtube in 24hours, whilst BTS Permission to Dance achieved 68.5 million in the same period of time. The difference is significant when added Big Bang’s and BTS overall award wins, a total of 117 in contrast to 460. Both groups are uniquely talented and exceptional performers that have been contributing greatly to the dissemination of Korean Pop Music on a global scale in their own inimitable ways. Both are exceptional in their own right and while the artists cannot, ought not, should not be compared for the grave injustice made in comparing one individual planet with one solar system, a contrast is merited and hence done. The reality, nonetheless, is about disengagement from a group that lives life humanly, learning and evolving with each challenge and mistake without a clean, perfect tag attached to it, demonstrating not only an inability to disassociate the person from the artist and the music but also an inability to understand the difference between a private and public life.

Keywords: K-Pop, big bang, BTS, music, public image, entertainment, korean entertainment

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2941 Early-Onset Asthma and Early Smoking Increase Risk of Bipolar Disorder in Adolescents and Young Adults

Authors: Meng-Huan Wu, Wei-Er Wang, Tsu-Nai Wang, Wei-Jian Hsu, Vincent Chin-Hung Chen

Abstract:

Objective: Studies have reported a strong link between asthma and bipolar disorder. We conducted a 17-year community-based large cohort study to examine the relationship between asthma, early smoking initiation, and bipolar disorder during adolescence and early adulthood. Methods: A total of 162,766 participants aged 11–16 years were categorized into asthma and non-asthma groups at baseline and compared within the observation period. Covariates during late childhood or adolescence included parental education, cigarette smoking by family members of participants, and participant’s gender, age, alcohol consumption, smoking, and exercise habits. Data for urbanicity, prednisone use, allergic comorbidity, and Charlson comorbidity index were acquired from the National Health Insurance Research Database. The Cox proportional-hazards model was used to evaluate the association between asthma and bipolar disorder. Results: Our findings revealed that asthma increased the risk of bipolar disorder after adjustment for key confounders in the Cox proportional hazard regression model (adjusted HR: 1.31, 95% CI: 1.12-1.53). Hospitalizations or visits to the emergency department for asthma exhibited a dose–response effect on bipolar disorder (adjusted HR: 1.59, 95% CI: 1.22-2.06). Patients with asthma with onset before 20 years of age who smoked during late childhood or adolescence had the greatest risk for bipolar disorder (adjusted HR: 3.10, 95% CI: 1.29-7.44). Conclusions: Patients newly diagnosed with asthma had a 1.3 times higher risk of developing bipolar disorder. Smoking during late childhood or adolescence increases the risk of developing bipolar disorder in patients with asthma.

Keywords: adolescence, asthma, smoking, bipolar disorder, early adulthood

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2940 Effects of Aerobic Dance on Systolic Blood Pressure in Stage 1 Hypertensive Individuals in Uganda

Authors: Loyce Nahwera, Joy Wachira, Edwin Kiptolo, Constance Nsibambi, Mshilla Maghanga, Timothy Makubuya

Abstract:

Introduction: Hypertension is one of the most prominent risk factors for cardiovascular diseases globally, and it can be modified through lifestyle interventions such as exercise. The objective of this study was to investigate the effects of a 12-week aerobic dance programme on systolic blood pressure (SBP) in stage 1 hypertensive individuals. Methods: This study employed an experimental research design. A total of 36 stage 1 hypertensive individuals who were randomly assigned into experimental and control groups completed the study. Systolic BP was measured using a mercury sphygmomanometer at baseline, mid-point and after the program. The experimental group participants trained 3 days a week, 45 minutes per session, at a moderate intensity of 40-60% of maximum oxygen consumption (VO2max) monitored by Garmin heart rate monitors. Data were analyzed using SPSS version 20. The significance level was set at p<0.05. A paired sample t-test was used to compare mean differences within the groups. Results: Data from the 36 participants (22 males and 14 females) (experimental; n=18, control; n=18) show that the experimental group had a mean SBP of 143.83±6.382 mmHg at baseline while the control had a mean of 137.61±6.400 mmHg. Following the end of a 6-week aerobic dance, the mean SBP of the experimental group reduced to 138.06±9.539 mmHg while that of the control marginally decreased to 137.00±8.073 mmHg. At the completion of a 12-week program, the mean SBP of the experimental group reduced to 136.33±9.191 mmHg, while that of the control marginally increased to 139.56±9.954 mmHg. This implies that both the 6-week and 12-week aerobic dance program reduced the SBP of the experimental group by 5.77±7.133 mmHg and 7.50±8.487 mmHg, respectively, while the control group fast reduced marginally by 0.61 before ultimately increasing by 1.95±7.974 mmHg at 12-weeks. The changes were statistically significant (p<0.05) at both 6 and 12 weeks of an aerobic dance program. Conclusion: The study concluded that aerobic dance is an effective non-pharmacological method for managing SBP of stage 1 hypertensive individuals both in the short-term (6 weeks) and long-term (12 weeks).

Keywords: aerobic dance, blood pressure, stage 1 hypertension, systolic blood pressure.

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2939 Engineering Topology of Photonic Systems for Sustainable Molecular Structure: Autopoiesis Systems

Authors: Moustafa Osman Mohammed

Abstract:

This paper introduces topological order in descried social systems starting with the original concept of autopoiesis by biologists and scientists, including the modification of general systems based on socialized medicine. Topological order is important in describing the physical systems for exploiting optical systems and improving photonic devices. The stats of topological order have some interesting properties of topological degeneracy and fractional statistics that reveal the entanglement origin of topological order, etc. Topological ideas in photonics form exciting developments in solid-state materials, that being; insulating in the bulk, conducting electricity on their surface without dissipation or back-scattering, even in the presence of large impurities. A specific type of autopoiesis system is interrelated to the main categories amongst existing groups of the ecological phenomena interaction social and medical sciences. The hypothesis, nevertheless, has a nonlinear interaction with its natural environment 'interactional cycle' for exchange photon energy with molecules without changes in topology. The engineering topology of a biosensor is based on the excitation boundary of surface electromagnetic waves in photonic band gap multilayer films. The device operation is similar to surface Plasmonic biosensors in which a photonic band gap film replaces metal film as the medium when surface electromagnetic waves are excited. The use of photonic band gap film offers sharper surface wave resonance leading to the potential of greatly enhanced sensitivity. So, the properties of the photonic band gap material are engineered to operate a sensor at any wavelength and conduct a surface wave resonance that ranges up to 470 nm. The wavelength is not generally accessible with surface Plasmon sensing. Lastly, the photonic band gap films have robust mechanical functions that offer new substrates for surface chemistry to understand the molecular design structure and create sensing chips surface with different concentrations of DNA sequences in the solution to observe and track the surface mode resonance under the influences of processes that take place in the spectroscopic environment. These processes led to the development of several advanced analytical technologies: which are; automated, real-time, reliable, reproducible, and cost-effective. This results in faster and more accurate monitoring and detection of biomolecules on refractive index sensing, antibody-antigen reactions with a DNA or protein binding. Ultimately, the controversial aspect of molecular frictional properties is adjusted to each other in order to form unique spatial structure and dynamics of biological molecules for providing the environment mutual contribution in investigation of changes due to the pathogenic archival architecture of cell clusters.

Keywords: autopoiesis, photonics systems, quantum topology, molecular structure, biosensing

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2938 Investigation of the Functional Impact of Amblyopia on Visual Skills in Children

Authors: Chinmay V. Deshpande

Abstract:

Purpose: To assess the efficiency of visual functions and visual skills in strabismic & anisometropic amblyopes and to assess visual acuity and contrast sensitivity in anisometropic amblyopes with spectacles & contact lenses. Method: In a prospective clinical study, 32 children ageing from 5 to 15 years presenting with amblyopia in a pediatric department of Shri Ganapati Netralaya Jalna, India, were assessed for a period of three & half months. Visual acuity was measured with Snellen’s and Bailey-Lovie log MAR charts whereas contrast sensitivity was measured with Pelli-Robson chart with spectacles and contact lenses. Saccadic movements were assessed with SCCO scoring criteria and accommodative facility was checked with ±1.50 DS flippers. Stereopsis was assessed with TNO test. Results: By using Wilcoxon sign rank test p-value < 0.05 (< 0.001), the mean linear visual acuity was 0.29 (≈ 6/21) and mean single optotype visual acuity found to be 0.36 (≈ 6/18). Mean visual acuity of 0.27(≈ 6/21) with spectacles improved to 0.33 (≈ 6/18) with contact lenses in amblyopic eyes. The mean Log MAR visual acuity with spectacles and contact lens were found to be 0.602( ≈6/24) and 0.531(≈ 6/21) respectively. The contrast threshold out of 20 amblyopic eyes shows that mean contrast threshold changed in 9 patients from spectacles 0.27 to contact lens 0.19 respectively. The mean accommodative facility assessed was 5.31(± 2.37). 24 subjects (75%) revealed marked saccadic defects on the test applied. 78% subjects didn’t show even gross stereoscopic ability on TNO test. Conclusion: This study supports the facts about amblyopia and associated deficits in visual skills which are claimed in previous studies. In addition, anisometropic amblyopia can be managed better with contact lenses.

Keywords: strabismus, anisometropia, amblyopia, contrast sensitivity, saccades, stereopsis

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2937 Improving Egg Production by Using Split-Phase Lighting Program

Authors: Hanan Al-Khalaifah, Afaf Al-Nasser

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The egg shell quality and oviposition in laying hens are influenced by a range of factors including strain of birds, age, nutrition, water quality, general stress, heat stress, disease, and lighting program inside houses. A layer experiment was conducted to investigate the effect of split-phase lighting program on egg production efficiency. Four different feeds and average phosphorus (av. P) levels were tested. Diet A was a ration with an av. P level of 0.471%; Diet B was a ration with an av. P level of 0.510%; Diet C contained an av. P level of 0.293%; and Diet D contained an av. P level of 0.327%. The split-phase lighting program tested was one that inserted a 7-hour dark period from 9 am to 4 pm to reduce the heat produced by the feeding increment and physical activity of the hens. Diet B produced significantly more eggs than Diet C, or Diet D. Diet A was not significantly different from any of the other diets. Diet B also had the best feed efficiency with the other three diets in the same order and significance as for egg production. Diet D produced eggshells significantly thicker than either Diet A, or Diet B. Diet C produced thicker eggshells than Diet B, whose shells were significantly thinner than the other three diets. There were no differences in egg size. From these data, it is apparent that the minimal av. P level for the Lohmann strain of layer in Kuwait is above 0.327%. There was no difference in egg production or eggshell thickness between the split-phase light treatment and the standard light program. There was no difference in oviposition frequency. The split-phase light used 3.66% less feed, however, which was significant. The standard light produced eggs that were significantly heavier (66.30g vs. 65.73g). These results indicate that considerable savings in feed costs could be attained by using split-phase lighting, especially when cooling is not very efficient.

Keywords: egg, laying, nutrition, oviposition

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2936 Deep Learning Prediction of Residential Radon Health Risk in Canada and Sweden to Prevent Lung Cancer Among Non-Smokers

Authors: Selim M. Khan, Aaron A. Goodarzi, Joshua M. Taron, Tryggve Rönnqvist

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Indoor air quality, a prime determinant of health, is strongly influenced by the presence of hazardous radon gas within the built environment. As a health issue, dangerously high indoor radon arose within the 20th century to become the 2nd leading cause of lung cancer. While the 21st century building metrics and human behaviors have captured, contained, and concentrated radon to yet higher and more hazardous levels, the issue is rapidly worsening in Canada. It is established that Canadians in the Prairies are the 2nd highest radon-exposed population in the world, with 1 in 6 residences experiencing 0.2-6.5 millisieverts (mSv) radiation per week, whereas the Canadian Nuclear Safety Commission sets maximum 5-year occupational limits for atomic workplace exposure at only 20 mSv. This situation is also deteriorating over time within newer housing stocks containing higher levels of radon. Deep machine learning (LSTM) algorithms were applied to analyze multiple quantitative and qualitative features, determine the most important contributory factors, and predicted radon levels in the known past (1990-2020) and projected future (2021-2050). The findings showed gradual downwards patterns in Sweden, whereas it would continue to go from high to higher levels in Canada over time. The contributory factors found to be the basement porosity, roof insulation depthness, R-factor, and air dynamics of the indoor environment related to human window opening behaviour. Building codes must consider including these factors to ensure adequate indoor ventilation and healthy living that can prevent lung cancer in non-smokers.

Keywords: radon, building metrics, deep learning, LSTM prediction model, lung cancer, canada, sweden

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2935 Toxicological Effects of Heavy Metals; Copper, Lead and Chromium on Brain and Liver Tissue of Grass Carp (Ctenopharyngodon idella)

Authors: Ahsan Khan, Nazish Shah, Muhammad Salman

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The present study deals with the toxicological effects of copper, lead and chromium on brain and liver tissues of grass carp (Ctenopharyngodon idella). The average length of experimental fish was 8.5 ± 5.5 cm and weighed 9.5 ± 6.5 g. Grass carp was exposed to lethal concentration (LC₁₅) of copper, lead and chromium for 24, 48, 72 and 96 hours respectively. (LC₁₅) for copper was 1.5, 1.4, 1.2 and 1mgL⁻¹. Similarly, LC₁₅ of lead was 250, 235, 225 and 216mgL⁻¹ while (LC₁₅) for chromium was 25.5, 22.5, 20 and 18mgL⁻¹ respectively. During the time of exposure against various doses of heavy metals the grass carp showed some behavioral changes. In the initial stages of experiment, the rapid movements and gulping of air were observed. Several times the fish tried to jump to scat from the toxic median. In addition, the accumulation of heavy metals in different tissues of grass carp particularly in liver and brain tissues were observed. Lead was highly accumulated in brain tissue after the exposure of fish for 24 and 48 hours, while highly accumulated in liver tissues after the exposure of fish for 72 and 96 hours. Chromium was highly accumulated in the liver tissues after the exposure of fish for 24 hours while its accumulation was found highly in the brain tissues after the exposure of fish for 48, 72 and 96 hours. Similarly, accumulation of copper concentration was found highly in brain tissues after the exposure of 48 and 96 hours while its accumulation was high in liver tissues after the exposure of 24 and 72 hours. Comparatively maximum accumulation of lead was found in brain and liver tissues of grass carp followed by chromium and copper. Furthermore, accumulation of these metals caused many abnormalities like gliosis, destruction of cell, change in cell shape and shrinkage of cells in brain tissue while in liver tissues aggregation in hepatocytes, widen space between cells and also destruction of cell was observed. These experiments and observations can be useful to monitor the aquatic pollution and quality of aquatic environment system.

Keywords: brain, grass carp, liver, lethal concentration, toxicity

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2934 The Influence of the Regional Sectoral Structure on the Socio-Economic Development of the Arkhangelsk Region

Authors: K. G. Sorokozherdyev, E. A. Efimov

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The socio-economic development of regions and countries is an important research issue. Today, in the face of many negative events in the global and regional economies, it is especially important to identify those areas that can serve as sources of economic growth and the basis for the well-being of the population. This study aims to identify the most important sectors of the economy of the Arkhangelsk region that can contribute to the socio-economic development of the region as a whole. For research, the Arkhangelsk region was taken as one of the typical Russian regions that do not have significant reserves of hydrocarbons nor there are located any large industrial complexes. In this regard, the question of possible origins of economic growth seems especially relevant. The basis of this study constitutes the distributed lag regression model (ADL model) developed by the authors, which is based on quarterly data on the socio-economic development of the Arkhangelsk region for the period 2004-2016. As a result, we obtained three equations reflecting the dynamics of three indicators of the socio-economic development of the region -the average wage, the regional GRP, and the birth rate. The influencing factors are the shares in GRP of such sectors as agriculture, mining, manufacturing, construction, wholesale and retail trade, hotels and restaurants, as well as the financial sector. The study showed that the greatest influence on the socio-economic development of the region is exerted by such industries as wholesale and retail trade, construction, and industrial sectors. The study can be the basis for forecasting and modeling the socio-economic development of the Arkhangelsk region in the short and medium term. It also can be helpful while analyzing the effectiveness of measures aimed at stimulating those or other industries of the region. The model can be used in developing a regional development strategy.

Keywords: regional economic development, regional sectoral structure, ADL model, Arkhangelsk region

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2933 Overview of Pre-Analytical Lab Errors in a Tertiary Care Hospital at Rawalpindi, Pakistan

Authors: S. Saeed, T. Butt, M. Rehan, S. Khaliq

Abstract:

Objective: To determine the frequency of pre-analytical errors in samples taken from patients for various lab tests at Fauji Foundation Hospital, Rawalpindi. Material and Methods: All the lab specimens for diagnostic purposes received at the lab from Fauji Foundation hospital, Rawalpindi indoor and outdoor patients were included. Total number of samples received in the lab is recorded in the computerized program made for the hospital. All the errors observed for pre-analytical process including patient identification, sampling techniques, test collection procedures, specimen transport/processing and storage were recorded in the log book kept for the purpose. Results: A total of 476616 specimens were received in the lab during the period of study including 237931 and 238685 from outdoor and indoor patients respectively. Forty-one percent of the samples (n=197976) revealed pre-analytical discrepancies. The discrepancies included Hemolyzed samples (34.8%), Clotted blood (27.8%), Incorrect samples (17.4%), Unlabeled samples (8.9%), Insufficient specimens (3.9%), Request forms without authorized signature (2.9%), Empty containers (3.9%) and tube breakage during centrifugation (0.8%). Most of these pre-analytical discrepancies were observed in samples received from the wards revealing that inappropriate sample collection by the medical staff of the ward, as most of the outdoor samples are collected by the lab staff who are properly trained for sample collection. Conclusion: It is mandatory to educate phlebotomists and paramedical staff particularly performing duties in the wards regarding timing and techniques of sampling/appropriate container to use/early delivery of the samples to the lab to reduce pre-analytical errors.

Keywords: pre analytical lab errors, tertiary care hospital, hemolyzed, paramedical staff

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2932 Computed Tomography Guided Bone Biopsies: Experience at an Australian Metropolitan Hospital

Authors: K. Hinde, R. Bookun, P. Tran

Abstract:

Percutaneous CT guided biopsies provide a fast, minimally invasive, cost effective and safe method for obtaining tissue for histopathology and culture. Standards for diagnostic yield vary depending on whether the tissue is being obtained for histopathology or culture. We present a retrospective audit from Western Health in Melbourne Australia over a 12-month period which aimed to determine the diagnostic yield, technical success and complication rate for CT guided bone biopsies and identify factors affecting these results. The digital imaging storage program (Synapse Picture Archiving and Communication System – Fujifilm Australia) was analysed with key word searches from October 2015 to October 2016. Nineteen CT guided bone biopsies were performed during this time. The most common referring unit was oncology, work up imaging included CT, MRI, bone scan and PET scan. The complication rate was 0%, overall diagnostic yield was 74% with a technical success of 95%. When performing biopsies for histologic analysis diagnostic yield was 85% and when performing biopsies for bacterial culture diagnostic yield was 60%. There was no significant relationship identified between size of lesion, distance of lesion to skin, lesion appearance on CT, the number of samples taken or gauge of needle to diagnostic yield or technical success. CT guided bone biopsy at Western Health meets the standard reported at other major clinical centres for technical success and safety. It is a useful investigation in identification of primary malignancy in distal bone metastases.

Keywords: bone biopsy, computed tomography, core biopsy, histopathology

Procedia PDF Downloads 189
2931 The Prevalence of Postpartum Stress among Jordanian Women

Authors: Khitam Ibrahem Shlash Mohammad

Abstract:

Background: Postnatal depression is a focus of considerable research attention, but little is known about the pattern of stress across this period. Objective: to investigate the prevalence of stress after childbirth for Jordanian women and identify associated risk factors. Method: Design: A descriptive cross-sectional study. Participants were recruited six to eight weeks postpartum, provided personal, social and obstetric information, and completed the stress subscale of Depression Anxiety and Stress Scale (DASS-S), the Maternity Social Support Scale (MSSS), and Perceived Self-Efficacy Scale (PSES). Setting: maternal and child health care clinics in four health care centres in Maan city in Southern Jordan. Participants: Arabic speaking women (n = 324) between the ages of 18 and 45 years, six to eight weeks postpartum, primiparous or multiparous at low risk for obstetric complications. Data collection took place between October 2015 and January 2016. Ethical clearance was obtained prior to data collection. Results: The prevalence of postpartum stress among Jordanian women was 39.8 %. A regression analysis revealed that occupation, low social support, financial problems, difficult marital relationships, difficult relationship with family-in-law, giving birth to a female baby, difficult childbirth, and low self-efficacy were associated with postpartum stress. Conclusions and implications for practice: Jordanian women need support during pregnancy, during and after childbirth. Postpartum emotional support and assessment of symptoms of stress need to be incorporated into routine practice. The opportunity for open discussion along with increased awareness and clarification of common misconceptions about postpartum stress is necessary.

Keywords: prevalence, postpartum, stress, Jordanian women

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2930 A Fact-Finding Analysis on the Expulsions Made under Title 42 in Us

Authors: Avi Shrivastava

Abstract:

Title 42, an emergency health decree, has forced the federal authorities to turn away asylum seekers and all other border crossers since last year. When Title 42 was first deployed in immigration detention centers, where many migrants are held when they arrive at the U.S.-Mexico border, the Trump administration embraced it as a strategy. Expulsions Policy and New Border Challenges will be examined in regard to Title 42 concerns. Humanitarian measures for refugees arriving at the US-Mexico border are the focus of this article. To a large extent, this article addresses the implications of the United States' use of Title 42 in expelling refugees and the possible ramifications of doing away with it. A secondary data collecting strategy was used to gather the information for this study, allowing researchers to examine a large number of previously collected data sets. Information about Title 42 may be found in a variety of places, such as scholarly publications, newspapers, books, and the internet. The inquiry employed qualitative and explanatory research approaches. The claim that 1.7 million individuals were forced to leave the country as a result of it was withdrawn. Since CBP and ICE were limited in their ability to process deportees, it employed a very random patchwork technique in selecting the expelled individuals. As a consequence, repeat offenders, particularly those who were single, got a reduced punishment. The government will be compelled to focus on long-overdue but vital border enhancements if expulsions are halted. Title 42 provisions may help expedite the processing of asylum and other types of humanitarian relief. The government is prepared for an increase in arrivals, but ending the program would lead to a return to arrival levels seen during the Title 42 period.

Keywords: migrants, refugees, title 42, medical, trump administration

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2929 Back to Nature: Addressing the German Nudist Movement’s Colonial Past and Its Repercussions

Authors: Saskia Köbschall

Abstract:

The idea of ‘being close to nature’ and the ways of achieving this proximity are socially and historically constructed, as are notions of nakedness and nudity. During the colonial period, nudity and clothedness functioned as instruments of racial domination. Nakedness became central to the colonialists’ thinking, to their binary of the ‘civilized’ and those ‘close to nature’, therefore turning the level of perceived unclothedness into a measurement of ‘civilization'. While being ‘one with nature’ continued to be a criterion of backwardness in the colonies, it emerged as a futuristic and avant-garde endeavor in the metropole: In Germany, at the height of its colonial expansion, the Life Reform Movement (Lebensreformbewegung) called for the liberation of the white body from the ‘constraints of civilization’, for its ‘return to nature’ via practices like nudism. Despite this simultaneity, the scholarship of the life reform and the nudist movement in particular does not address the colonial past of the movement or its repercussions in the present. Taking the biography of prominent life reformist Hans Paasche (1881 - 1920) as a starting point, this paper explores the work of imperial legacies in the history and present of the German nudist movement. Paasche started his career as a German colonial officer, participating in the brutal obliteration of the Maji-Maji uprising (1905/06) that claimed the lives of nearly 200.000 people. Once a passionate game hunter, he later became a known nature conservationist; once a self-proclaimed explorer of Africa, he later became one of the most prominent advocates of nudism and vegetarianism. The paper joins conceptual and historical research in order to address the German nudist movement’s colonial past and understand its repercussions in the present.

Keywords: Germany, life reform, colonialism, archives, nudity, nature

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2928 The Use of a Miniature Bioreactor as Research Tool for Biotechnology Process Development

Authors: Muhammad Zainuddin Arriafdi, Hamudah Hakimah Abdullah, Mohd Helmi Sani, Wan Azlina Ahmad, Muhd Nazrul Hisham Zainal Alam

Abstract:

The biotechnology process development demands numerous experimental works. In laboratory environment, this is typically carried out using a shake flask platform. This paper presents the design and fabrication of a miniature bioreactor system as an alternative research tool for bioprocessing. The working volume of the reactor is 100 ml, and it is made of plastic. The main features of the reactor included stirring control, temperature control via the electrical heater, aeration strategy through a miniature air compressor, and online optical cell density (OD) sensing. All sensors and actuators integrated into the reactor was controlled using an Arduino microcontroller platform. In order to demonstrate the functionality of such miniature bioreactor concept, series of batch Saccharomyces cerevisiae fermentation experiments were performed under various glucose concentrations. Results attained from the fermentation experiments were utilized to solve the Monod equation constants, namely the saturation constant, Ks, and cells maximum growth rate, μmax as to further highlight the usefulness of the device. The mixing capacity of the reactor was also evaluated. It was found that the results attained from the miniature bioreactor prototype were comparable to results achieved using a shake flask. The unique features of the device as compared to shake flask platform is that the reactor mixing condition is much more comparable to a lab-scale bioreactor setup. The prototype is also integrated with an online OD sensor, and as such, no sampling was needed to monitor the progress of the reaction performed. Operating cost and medium consumption are also low and thus, making it much more economical to be utilized for biotechnology process development compared to lab-scale bioreactors.

Keywords: biotechnology, miniature bioreactor, research tools, Saccharomyces cerevisiae

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2927 History and Development of the Printing Industry in Nigeria: The Case of Zaria

Authors: Eunice S. A. Jeje

Abstract:

The world over no society is homogeneous therefore, there is the presence of migrants from different places who resides in different places due to certain factors that either attracts them to these places or forced them out of their initial environment. The bottom line is that they moved out of their initial environment to other places for survival, therefore, engage in social cum economic activities to sustain a living which at the same time has enhanced the development and growth of such communities. In the case of Zaria, the Yoruba people are one of the major migrant groups who had moved into Zaria over time. Out of the numerous roles they played in the development of Zaria, the establishment and sustenance of the printing industry are one. Selected Yoruba migrants from the South-west of the country who were skilled in the profession due to stiff competition in their region and the desire to eke out a living had to move into Northern Nigeria to establish printing outlets which have consequently developed to what it is today. The printing industry is one of the avenues to which information and knowledge are disseminated. This is achieved through the publishing of texts, books, Newspapers, Magazines, pamphlets, etc. to convey information to the wider public, in this bid, it leads to the spread of knowledge, ideas, and information. The introduction of printing industry to Nigeria was in the 19th century during the incursion of the missionaries to the West Coast of Africa, but it was not until the colonial period (20th Century) that its presence could be felt in the interior of Nigeria especially in Northern Nigeria and to be specific in Zaria. In essence, the influence of the Yoruba people in the growth and expansion of printing industry in Zaria cannot be over emphasized. It is the thrust of this research to bring to the fore through the use of primary and secondary sources the role and contributions of the Yoruba people in the development of the print industry in Zaria and also showcase the importance of migrants in the development of societies.

Keywords: development, printing industry, Yoruba, Zaria

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2926 Engineering of Filtration Systems in Egyptian Cement Plants: Industrial Case Study

Authors: Mohamed. A. Saad

Abstract:

The paper represents a case study regarding the conversion of Electro-Static Precipitators (ESP`s) into Fabric Filters (FF). Seven cement production companies were established in Egypt during the period 1927 to 1980 and 6 new companies were established to cope with the increasing cement demand in 1980's. The cement production market shares in Egypt indicate that there are six multinational companies in the local market, they are interested in the environmental conditions improving and so decided to achieve emission reduction project. The experimental work in the present study is divided into two main parts: (I) Measuring Efficiency of Filter Fabrics with detailed description of a designed apparatus. The paper also reveals the factors that should be optimized in order to assist problem diagnosis, solving and increasing the life of bag filters. (II) Methods to mitigate dust emissions in Egyptian cement plants with a special focus on converting the Electrostatic Precipitators (ESP`s) into Fabric Filters (FF) using the same ESP casing, bottom hoppers, dust transportation system, and ESP ductwork. Only the fan system for the higher pressure drop with the fabric filter was replaced. The proper selection of bag material was a prime factor with regard to gas composition, temperature and particle size. Fiberglass with PTFE membrane coated bags was selected. This fabric is rated for a continuous temperature of 250 C and a surge temperature of 280C. The dust emission recorded was less than 20 mg/m3 from the production line fitted with fabric filters which is super compared with the ESP`s working lines stack.

Keywords: Engineering Electrostatic Precipitator, filtration, dust collectors, cement

Procedia PDF Downloads 240
2925 Rd-PLS Regression: From the Analysis of Two Blocks of Variables to Path Modeling

Authors: E. Tchandao Mangamana, V. Cariou, E. Vigneau, R. Glele Kakai, E. M. Qannari

Abstract:

A new definition of a latent variable associated with a dataset makes it possible to propose variants of the PLS2 regression and the multi-block PLS (MB-PLS). We shall refer to these variants as Rd-PLS regression and Rd-MB-PLS respectively because they are inspired by both Redundancy analysis and PLS regression. Usually, a latent variable t associated with a dataset Z is defined as a linear combination of the variables of Z with the constraint that the length of the loading weights vector equals 1. Formally, t=Zw with ‖w‖=1. Denoting by Z' the transpose of Z, we define herein, a latent variable by t=ZZ’q with the constraint that the auxiliary variable q has a norm equal to 1. This new definition of a latent variable entails that, as previously, t is a linear combination of the variables in Z and, in addition, the loading vector w=Z’q is constrained to be a linear combination of the rows of Z. More importantly, t could be interpreted as a kind of projection of the auxiliary variable q onto the space generated by the variables in Z, since it is collinear to the first PLS1 component of q onto Z. Consider the situation in which we aim to predict a dataset Y from another dataset X. These two datasets relate to the same individuals and are assumed to be centered. Let us consider a latent variable u=YY’q to which we associate the variable t= XX’YY’q. Rd-PLS consists in seeking q (and therefore u and t) so that the covariance between t and u is maximum. The solution to this problem is straightforward and consists in setting q to the eigenvector of YY’XX’YY’ associated with the largest eigenvalue. For the determination of higher order components, we deflate X and Y with respect to the latent variable t. Extending Rd-PLS to the context of multi-block data is relatively easy. Starting from a latent variable u=YY’q, we consider its ‘projection’ on the space generated by the variables of each block Xk (k=1, ..., K) namely, tk= XkXk'YY’q. Thereafter, Rd-MB-PLS seeks q in order to maximize the average of the covariances of u with tk (k=1, ..., K). The solution to this problem is given by q, eigenvector of YY’XX’YY’, where X is the dataset obtained by horizontally merging datasets Xk (k=1, ..., K). For the determination of latent variables of order higher than 1, we use a deflation of Y and Xk with respect to the variable t= XX’YY’q. In the same vein, extending Rd-MB-PLS to the path modeling setting is straightforward. Methods are illustrated on the basis of case studies and performance of Rd-PLS and Rd-MB-PLS in terms of prediction is compared to that of PLS2 and MB-PLS.

Keywords: multiblock data analysis, partial least squares regression, path modeling, redundancy analysis

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2924 Factors Affecting the Ultimate Compressive Strength of the Quaternary Calcarenites, North Western Desert, Egypt

Authors: M. A. Rashed, A. S. Mansour, H. Faris, W. Afify

Abstract:

The calcarenites carbonate rocks of the Quaternary ridges, which extend along the northwestern Mediterranean coastal plain of Egypt, represent an excellent model for the transformation of loose sediments to real sedimentary rocks by the different stages of meteoric diagenesis. The depositional and diagenetic fabrics of the rocks, in addition to the strata orientation, highly affect their ultimate compressive strength and other geotechnical properties. There is a marked increase in the compressive strength (UCS) from the first to the fourth ridge rock samples. The lowest values are related to the loose packing, weakly cemented aragonitic ooid sediments with high porosity, besides the irregularly distributed of cement, which result in decreasing the ability of these rocks to withstand crushing under direct pressure. The high (UCS) values are attributed to the low porosity, the presence of micritic cement, the reduction in grain size and the occurrence of micritization and calcretization processes. The strata orientation has a notable effect on the measured (UCS). The lowest values have been recorded for the samples cored in the inclined direction; whereas the highest values have been noticed in most samples cored in the vertical and parallel directions to bedding plane. In case of the inclined direction, the bedding planes were oriented close to the plane of maximum shear stress. The lowest and highest anisotropy values have been recorded for the first and the third ridges rock samples, respectively, which may attributed to the relatively homogeneity and well sorted grain-stone of the first ridge rock samples, and relatively heterogeneity in grain and pore size distribution and degree of cementation of the third ridge rock samples, besides, the abundance of shell fragments with intra-particle pore spaces, which may produce lines of weakness within the rock.

Keywords: compressive strength, anisotropy, calcarenites, Egypt

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2923 Effect of Modulation Factors on Tomotherapy Plans and Their Quality Analysis

Authors: Asawari Alok Pawaskar

Abstract:

This study was aimed at investigating quality assurance (QA) done with IBA matrix, the discrepan­cies observed for helical tomotherapy plans. A selection of tomotherapy plans that initially failed the with Matrix process was chosen for this investigation. These plans failed the fluence analysis as assessed using gamma criteria (3%, 3 mm). Each of these plans was modified (keeping the planning constraints the same), beamlets rebatched and reoptimized. By increasing and decreasing the modula­tion factor, the fluence in a circumferential plane as measured with a diode array was assessed. A subset of these plans was investigated using varied pitch values. Factors for each plan that were examined were point doses, fluences, leaf opening times, planned leaf sinograms, and uniformity indices. In order to ensure that the treatment constraints remained the same, the dose-volume histograms (DVHs) of all the modulated plans were compared to the original plan. It was observed that a large increase in the modulation factor did not significantly improve DVH unifor­mity, but reduced the gamma analysis pass rate. This also increased the treatment delivery time by slowing down the gantry rotation speed which then increases the maximum to mean non-zero leaf open time ratio. Increasing and decreasing the pitch value did not substantially change treatment time, but the delivery accuracy was adversely affected. This may be due to many other factors, such as the complexity of the treatment plan and site. Patient sites included in this study were head and neck, breast, abdomen. The impact of leaf tim­ing inaccuracies on plans was greater with higher modulation factors. Point-dose measurements were seen to be less susceptible to changes in pitch and modulation factors. The initial modulation factor used by the optimizer, such that the TPS generated ‘actual’ modulation factor within the range of 1.4 to 2.5, resulted in an improved deliverable plan.

Keywords: dose volume histogram, modulation factor, IBA matrix, tomotherapy

Procedia PDF Downloads 166
2922 Simulation Study on Effects of Surfactant Properties on Surfactant Enhanced Oil Recovery from Fractured Reservoirs

Authors: Xiaoqian Cheng, Jon Kleppe, Ole Torsaeter

Abstract:

One objective of this work is to analyze the effects of surfactant properties (viscosity, concentration, and adsorption) on surfactant enhanced oil recovery at laboratory scale. The other objective is to obtain the functional relationships between surfactant properties and the ultimate oil recovery and oil recovery rate. A core is cut into two parts from the middle to imitate the matrix with a horizontal fracture. An injector and a producer are at the left and right sides of the fracture separately. The middle slice of the core is used as the model in this paper, whose size is 4cm x 0.1cm x 4.1cm, and the space of the fracture in the middle is 0.1 cm. The original properties of matrix, brine, oil in the base case are from Ekofisk Field. The properties of surfactant are from literature. Eclipse is used as the simulator. The results are followings: 1) The viscosity of surfactant solution has a positive linear relationship with surfactant oil recovery time. And the relationship between viscosity and oil production rate is an inverse function. The viscosity of surfactant solution has no obvious effect on ultimate oil recovery. Since most of the surfactant has no big effect on viscosity of brine, the viscosity of surfactant solution is not a key parameter of surfactant screening for surfactant flooding in fractured reservoirs. 2) The increase of surfactant concentration results a decrease of oil recovery rate and an increase of ultimate oil recovery. However, there are no functions could describe the relationships. Study on economy should be conducted because of the price of surfactant and oil. 3) In the study of surfactant adsorption, assume that the matrix wettability is changed to water-wet when the surfactant adsorption is to the maximum at all cases. And the ratio of surfactant adsorption and surfactant concentration (Cads/Csurf) is used to estimate the functional relationship. The results show that the relationship between ultimate oil recovery and Cads/Csurf is a logarithmic function. The oil production rate has a positive linear relationship with exp(Cads/Csurf). The work here could be used as a reference for the surfactant screening of surfactant enhanced oil recovery from fractured reservoirs. And the functional relationships between surfactant properties and the oil recovery rate and ultimate oil recovery help to improve upscaling methods.

Keywords: fractured reservoirs, surfactant adsorption, surfactant concentration, surfactant EOR, surfactant viscosity

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2921 The Aesthetic and Critiques of Weimar Democracy: The Counter and Complement to Carl Schmitt’s Political Myth

Authors: Peter Jin

Abstract:

Ever since the recent resurgence of interest in political theorist Carl Schmitt’s work, much of the current analysis on Schmitt has fo-cused on evaluating Schmitt’s legacy by exposing contradictions in his rationale. Rather than condemn such contradictions, this paper instead seeks to analyze these contradictions in an effort to better understand the radical shift in Schmitt’s intellectual trajectory from an astute critic of liberal democracy to a fascist apologist towards the end of the Weimar period. An essential part of this change is his interest in what Schmitt called ‘the emergence of aesthetics.’ Schmitt diagnosed the underlying issue with the aesthetic in the political sphere to be its irrationalism, indifference, and indeci-siveness. For Schmitt, the latter two of these were especially prob-lematic for two of his key concepts: the ‘political’ and ‘the shared historical reality.’ Schmitt’s radical depiction of ‘the political’ as an existential opposition of allegiances that necessitated a state of emergency and a decisionist sovereign political struggle required an equally radical justification, or Schmitt’s call for ‘a shared his-torical reality’ not based in historical fact yet able to mobilize the masses. In this way, Schmitt clearly condemns the indifferent, indecisive aesthetic that runs against his decisionist, action-oriented political theory. Yet despite his firm stance against aestheticism, Schmitt himself used the evocative and irrational power of aesthet-icism as a tool to present his own ‘political myth’ that compelled believers to join in decisive unity against a common enemy. In short, Schmitt’s contradictions on aestheticism and his creation of a ‘political myth’ suggest that Schmitt’s underlying conflict with aestheticism was not as much of an issue of irrationality as it was a chronic preoccupation with coercing concrete action at the expense of rational deliberation.

Keywords: aesthetics of the political, Carl Schmitt, political myth, Weimar democracy

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