Search results for: accelerated failure time model
15877 An Experimental Study of Diffuser-Enhanced Propeller Hydrokinetic Turbines
Authors: Matheus Nunes, Rafael Mendes, Taygoara Felamingo Oliveira, Antonio Brasil Junior
Abstract:
Wind tunnel experiments of horizontal axis propeller hydrokinetic turbines model were carried out, in order to determine the performance behavior for different configurations and operational range. The present experiments introduce the use of two different geometries of rear diffusers to enhance the performance of the free flow machine. The present paper reports an increase of the power coefficient about 50%-80%. It represents an important feature that has to be taken into account in the design of this kind of machine.Keywords: diffuser-enhanced turbines, hydrokinetic turbine, wind tunnel experiments, micro hydro
Procedia PDF Downloads 26615876 Realization and Characterization of TiN Coating and Metal Working Application
Authors: Nadjette Belhamra, Abdelouahed Chala, Ibrahim Guasmi
Abstract:
Titanium nitride coatings have been extensively used in industry, such as in cutting tools. TiN coating were deposited by chemical vapour deposition (CVD) on carbide insert at a temperature between 850°C and 1100°C, which often exceeds the hardening treatment temperature of the metals. The objective of this work is to realize, to characterize of TiN coating and to apply it in the turning of steel 42CrMo4 under lubrification. Various experimental techniques were employed for the microstructural characterization of the coatings, e. g., X-ray diffraction (XRD), scanning electron microscope (SEM) model JOEL JSM-5900 LV, equipped with energy dispersive X-ray (EDX). The results show that TiN-coated demonstrate a good wear resistance.Keywords: hard coating TiN, carbide inserts, machining, turning, wear
Procedia PDF Downloads 54415875 Reducing Diagnostic Error in Australian Emergency Departments Using a Behavioural Approach
Authors: Breanna Wright, Peter Bragge
Abstract:
Diagnostic error rates in healthcare are approximately 10% of cases. Diagnostic errors can cause patient harm due to inappropriate, inadequate or delayed treatment, and such errors contribute heavily to medical liability claims globally. Therefore, addressing diagnostic error is a high priority. In most cases, diagnostic errors are the result of faulty information synthesis rather than lack of knowledge. Specifically, the majority of diagnostic errors involve cognitive factors, and in particular, cognitive biases. Emergency Departments are an environment with heightened risk of diagnostic error due to time and resource pressures, a frequently chaotic environment, and patients arriving undifferentiated and with minimal context. This project aimed to develop a behavioural, evidence-informed intervention to reduce diagnostic error in Emergency Departments through co-design with emergency physicians, insurers, researchers, hospital managers, citizens and consumer representatives. The Forum Process was utilised to address this aim. This involves convening a small (4 – 6 member) expert panel to guide a focused literature and practice review; convening of a 10 – 12 person citizens panel to gather perspectives of laypeople, including those affected by misdiagnoses; and a 18 – 22 person structured stakeholder dialogue bringing together representatives of the aforementioned stakeholder groups. The process not only provides in-depth analysis of the problem and associated behaviours, but brings together expertise and insight to facilitate identification of a behaviour change intervention. Informed by the literature and practice review, the Citizens Panel focused on eliciting the values and concerns of those affected or potentially affected by diagnostic error. Citizens were comfortable with diagnostic uncertainty if doctors were honest with them. They also emphasised the importance of open communication between doctors and patients and their families. Citizens expect more consistent standards across the state and better access for both patients and their doctors to patient health information to avoid time-consuming re-taking of long patient histories and medication regimes when re-presenting at Emergency Departments and to reduce the risk of unintentional omissions. The structured Stakeholder Dialogue focused on identifying a feasible behavioural intervention to review diagnoses in Emergency Departments. This needed to consider the role of cognitive bias in medical decision-making; contextual factors (in Victoria, there is a legislated 4-hour maximum time between ED triage and discharge / hospital admission); resource availability; and the need to ensure the intervention could work in large metropolitan as well as small rural and regional ED settings across Victoria. The identified behavioural intervention will be piloted in approximately ten hospital EDs across Victoria, Australia. This presentation will detail the findings of all review and consultation activities, describe the behavioural intervention developed and present results of the pilot trial.Keywords: behavioural intervention, cognitive bias, decision-making, diagnostic error
Procedia PDF Downloads 12315874 Laser Cooling of Internal Degrees of Freedom of Molecules: Cesium Case
Authors: R. Horchani
Abstract:
Optical pumping technique with laser fields combined with photo-association of ultra-cold atoms leads to control on demand the vibrational and/or the rotational population of molecules. Here, we review the basic concepts and main steps should be followed, including the excitation schemes and detection techniques we use to achieve the ro-vibrational cooling of Cs2 molecules. We also discuss the extension of this technique to other molecules. In addition, we present a theoretical model used to support the experiment. These simulations can be widely used for the preparation of various experiments since they allow the optimization of several important experimental parameters.Keywords: cold molecule, photo-association, optical pumping, vibrational and rotational cooling
Procedia PDF Downloads 29415873 Modified Fractional Curl Operator
Authors: Rawhy Ismail
Abstract:
Applying fractional calculus in the field of electromagnetics shows significant results. The fractionalization of the conventional curl operator leads to having additional solutions to an electromagnetic problem. This work restudies the concept of the fractional curl operator considering fractional time derivatives in Maxwell’s curl equations. In that sense, a general scheme for the wave loss term is introduced and the degree of freedom of the system is affected through imposing the new fractional parameters. The conventional case is recovered by setting all fractional derivatives to unity.Keywords: curl operator, fractional calculus, fractional curl operators, Maxwell equations
Procedia PDF Downloads 47715872 The Effects of Cultural Distance and Institutions on Foreign Direct Investment Choices: Evidence from Turkey and China
Authors: Nihal Kartaltepe Behram, Göksel Ataman, Dila Okçu
Abstract:
With the development of foreign direct investments, the social, cultural, political and economic interactions between countries and institutions have become visible and they have become determining factors for the strategic structuring and market goals. In this context the purpose of this study is to investigate the effects of cultural distance and institutions on foreign direct investment choices in terms of location and investment model. For international establishments, the concept of culture, as well as the concept of cultural distance, is taken specifically into consideration, especially in the selection of methods for entering the market. In the researches and empirical studies conducted, a direct relationship between cultural distance and foreign direct investments is set and institutions and effective variable factors are examined at the level of defining the investment types. When the detailed calculation strategies and empirical researches and studies are taken into consideration, the most common methods for determining the direct investment model, considering the cultural distances, are full-ownership enterprises and joint ventures. Also, when all of the factors affecting the investments are taken into consideration, it was seen that the effect of institutions such as Government Intervention, Intellectual Property Rights, Corruption and Contract Enforcements is very important. Furthermore agglomeration is more intense and effective on the investment, compared to other factors. China has been selected as the target country, due to its effectiveness in world economy and its contributions to developing countries, which has commercial relationships with. Qualitative research methods are used for this study conducted, to measure the effects of determinative variable factors in the hypotheses of study, on the direct foreign investors and to evaluate the findings. In this study in-depth interview is used as a data collection method and the data analysis is made through descriptive analysis. Foreign Direct Investments are so reactive to institutions and cultural distance is identified by all interviews and analysis. On the other hand, agglomeration is the most strong determiner factor on foreign direct investors in Chinese Market. The reason of this factors, which comprise the sectorial aggregate, are not the strongest factors as agglomeration that the most important finding. We expect that this study became a beneficial guideline for developed and developing countries and local and national institutions’ strategic plans.Keywords: China, cultural distance, Foreign Direct Investments, institutions
Procedia PDF Downloads 41315871 Application of Shore Protective Structures in Optimum Land Using of Defense Sites Located in Coastal Cities
Authors: Mir Ahmad Lashteh Neshaei, Hamed Afsoos Biria, Ata Ghabraei, Mir Abdolhamid Mehrdad
Abstract:
Awareness of effective land using issues in coastal area including protection of natural ecosystems and coastal environment due to the increasing of human life along the coast is of great importance. There are numerous valuable structures and heritages which are located in defence sites and waterfront area. Marine structures such as groins, sea walls and detached breakwaters are constructed in coast to improve the coast stability against bed erosion due to changing wave and climate pattern. Marine mechanisms and interaction with the shore protection structures need to be intensively studied. Groins are one of the most prominent structures that are used in shore protection to create a safe environment for coastal area by maintaining the land against progressive coastal erosion. The main structural function of a groin is to control the long shore current and littoral sediment transport. This structure can be submerged and provide the necessary beach protection without negative environmental impact. However, for submerged structures adopted for beach protection, the shoreline response to these structures is not well understood at present. Nowadays, modelling and computer simulation are used to assess beach morphology in the vicinity of marine structures to reduce their environmental impact. The objective of this study is to predict the beach morphology in the vicinity of submerged groins and comparison with non-submerged groins with focus on a part of the coast located in Dahane sar Sefidrood, Guilan province, Iran where serious coast erosion has occurred recently. The simulations were obtained using a one-line model which can be used as a first approximation of shoreline prediction in the vicinity of groins. The results of the proposed model are compared with field measurements to determine the shape of the coast. Finally, the results of the present study show that using submerged groins can have a good efficiency to control the beach erosion without causing severe environmental impact to the coast. The important outcome from this study can be employed in optimum designing of defence sites in the coastal cities to improve their efficiency in terms of re-using the heritage lands.Keywords: submerged structures, groin, shore protective structures, coastal cities
Procedia PDF Downloads 31115870 On-Farm Mechanized Conservation Agriculture: Preliminary Agro-Economic Performance Difference between Disc Harrowing, Ripping and No-Till
Authors: Godfrey Omulo, Regina Birner, Karlheinz Koller, Thomas Daum
Abstract:
Conservation agriculture (CA) as a climate-resilient and sustainable practice have been carried out for over three decades in Zambia. However, its continued promotion and adoption has been predominantly on a small-scale basis. Despite the plethora of scholarship pointing to the positive benefits of CA in regard to enhanced yield, profitability, carbon sequestration and minimal environmental degradation, these have not stimulated commensurate agricultural extensification desired for Zambia. The objective of this study was to investigate the potential differences between mechanized conventional and conservation tillage practices on operation time, fuel consumption, labor costs, soil moisture retention, soil temperature and crop yield. An on-farm mechanized conservation agriculture (MCA) experiment arranged in a randomized complete block design with four replications was used. The research was conducted on a 15 ha of sandy loam rainfed land: soybeans on 7ha with plot dimensions of 24 m by 210 m and maize on 8ha with plot dimensions of 24 m by 250 m. The three tillage treatments were: residue burning followed by disc harrowing, ripping tillage and no-till. The crops were rotated in two subsequent seasons. All operations were done using a 60hp 2-wheel tractor, a disc harrow, a two-tine ripper and a two-row planter. Soil measurements and the agro-economic factors were recorded for two farming seasons. The season results showed that the yield of maize and soybeans under no-till and ripping tillage practices were not significantly different from the conventional burning and discing. But, there was a significant difference in soil moisture content between no-till (25.31SFU±2.77) and disced (11.91SFU±0.59) plots at depths from 10-60 cm. Soil temperature in no-till plots (24.59°C±0.91) was significantly lower compared to the disced plots (26.20°C±1.75) at the depths 15 cm and 45 cm. For maize, there was a significant difference in operation time between disc-harrowed (3.68hr/ha±1.27) and no-till (1.85hr/ha±0.04) plots, and a significant difference in cost of labor between disc-harrowed (45.45$/ha±19.56) and no-till (21.76$/ha) plots. There was no significant difference in fuel consumption between ripping and disc-harrowing and direct seeding. For soybeans, there was a significant difference in operation time between no-tillage (1.96hr/ha±0.31) and ripping (3.34hr/ha±0.53) and disc harrowing (3.30hr/ha±0.16). Further, fuel consumption and labor on no-till plots were significantly different from both the ripped and disc-harrowed plots. The high seed emergence percentage on maize disc-harrowed plot (93.75%±5.87) was not significantly different from ripping and no-till plots. Again, the high seed emergence percentage for the soybean ripped plot (93.75%±13.03) had no significant difference with discing and ripping. The results show that it is economically sound and timesaving to practice MCA and get viable yields compared to conventional farming. This research fills the gap on the potential of MCA in the context of Zambia and its profitability in incentivizing policymakers to invest in appropriate and sustainable machinery and implements for extensive agricultural production.Keywords: climate-smart agriculture, labor cost, mechanized conservation agriculture, soil moisture, Zambia
Procedia PDF Downloads 14215869 Dense and Quality Urban Living: A Comparative Study on Architectural Solutions in the European City
Authors: Flavia Magliacani
Abstract:
The urbanization of the last decades and its resulting urban growth entail problems both for environmental and economic sustainability. From this perspective, sustainable settlement development requires a horizontal decrease in the existing urban structure in order to enhance its greater concentration. Hence, new stratifications of the city fabric and architectural strategies ensuring high-density settlement models are possible solutions. However, although increasing housing density is necessary, it is not sufficient. Guaranteeing the quality of living is, indeed, equally essential. In order to meet this objective, many other factors come to light, namely the relationship between private and public spaces, the proximity to services, the accessibility of public transport, the local lifestyle habits, and the social needs. Therefore, how to safeguard both quality and density in human habitats? The present paper attempts to answer the previous main research question by addressing several sub-questions: Which architectural types meet the dual need for urban density and housing quality? Which project criteria should be taken into consideration by good design practices? What principles are desirable for future planning? The research will analyse different architectural responses adopted in four European cities: Paris, Lion, Rotterdam, and Amsterdam. In particular, it will develop a qualitative and comparative study of two specific architectural solutions which integrate housing density and quality living. On the one hand, the so-called 'self-contained city' model, on the other hand, the French 'Habitat Dense Individualisé' one. The structure of the paper will be as follows: the first part will develop a qualitative evaluation of some case studies, emblematic examples of the two above said architectural models. The second part will focus on the comparison among the chosen case studies. Finally, some conclusions will be drawn. The methodological approach, therefore, combines qualitative and comparative research. Parameters will be defined in order to highlight potential and criticality of each model in light of an interdisciplinary view. In conclusion, the present paper aims at shading light on design approaches which ensure a right balance between density and quality of the urban living in contemporary European cities.Keywords: density, future design, housing quality, human habitat
Procedia PDF Downloads 9815868 One-Stage Conversion of Adjustable Gastric Band to One-Anastomosis Gastric Bypass Versus Sleeve Gastrectomy : A Single-Center Experience With a Short and Mid-term Follow-up
Authors: Basma Hussein Abdelaziz Hassan, Kareem Kamel, Philobater Bahgat Adly Awad, Karim Fahmy
Abstract:
Background: Laparoscopic adjustable gastric band was one of the most applied and common bariatric procedures in the last 8 years. However; the failure rate was very high, reaching approximately 60% of the patients not achieving the desired weight loss. Most patients sought another revisional surgery. In which, we compared two of the most common weight loss surgeries performed nowadays: the laparoscopic sleeve gastrectomy and laparoscopic one- anastomosis gastric bypass. Objective: To compare the weight loss and postoperative outcomes among patients undergoing conversion laparoscopic one-anastomosis gastric bypass (cOAGB) and laparoscopic sleeve gastrectomy (cSG) after a failed laparoscopic adjustable gastric band (LAGB). Patients and Methods: A prospective cohort study was conducted from June 2020 to June 2022 at a single medical center, which included 77 patients undergoing single-stage conversion to (cOAGB) vs (cSG). Patients were reassessed for weight loss, comorbidities remission, and post-operative complications at 6, 12, and 18 months. Results: There were 77 patients with failed LAGB in our study. Group (I) was 43 patients who underwent cOAGB and Group (II) was 34 patients who underwent cSG. The mean age of the cOAGB group was 38.58. While in the cSG group, the mean age was 39.47 (p=0.389). Of the 77 patients, 10 (12.99%) were males and 67 (87.01%) were females. Regarding Body mass index (BMI), in the cOAGB group the mean BMI was 41.06 and in the cSG group the mean BMI was 40.5 (p=0.042). The two groups were compared postoperative in relation to EBWL%, BMI, and the co-morbidities remission within 18 months follow-up. The BMI was calculated post-operative at three visits. After 6 months of follow-up, the mean BMI in the cOAGB group was 34.34, and the cSG group was 35.47 (p=0.229). In 12-month follow-up, the mean BMI in the cOAGB group was 32.69 and the cSG group was 33.79 (p=0.2). Finally, the mean BMI after 18 months of follow-up in the cOAGB group was 30.02, and in the cSG group was 31.79 (p=0.001). Both groups had no statistically significant values at 6 and 12 months follow-up with p-values of 0.229, and 0.2 respectively. However, patients who underwent cOAGB after 18 months of follow-up achieved lower BMI than those who underwent cSG with a statistically significant p-value of 0.005. Regarding EBWL% there was a statistically significant difference between the two groups. After 6 months of follow-up, the mean EBWL% in the cOAGB group was 35.9% and the cSG group was 33.14%. In the 12-month follow-up, the EBWL % mean in the cOAGB group was 52.35 and the cSG group was 48.76 (p=0.045). Finally, the mean EBWL % after 18 months of follow-up in the cOAGB group was 62.06 ±8.68 and in the cSG group was 55.58 ±10.87 (p=0.005). Regarding comorbidities remission; Diabetes mellitus remission was found in 22 (88%) patients in the cOAGB group and 10 (71.4%) patients in the cSG group with (p= 0.225). Hypertension remission was found in 20 (80%) patients in the cOAGB group and 14 (82.4%) patients in the cSG group with (p=1). In addition, dyslipidemia remission was found in 27(87%) patients in cOAGB group and 17(70%) patients in the cSG group with (p=0.18). Finally, GERD remission was found in about 15 (88.2%) patients in the cOAGB group and 6 (60%) patients in the cSG group with (p=0.47). There are no statistically significant differences between the two groups in the post-operative data outcomes. Conclusion: This study suggests that the conversion of LAGB to either cOAGB or cSG could be feasibly performed in a single-stage operation. cOAGB had a significant difference as regards the weight loss results than cSG among the mid-term follow-up. However, there is no significant difference in the postoperative complications and the resolution of the co-morbidities. Therefore, cOAGB could provide a reliable alternative but needs to be substantiated in future long-term studies.Keywords: laparoscopic, gastric banding, one-anastomosis gastric bypass, Sleeve gastrectomy, revisional surgery, weight loss
Procedia PDF Downloads 4815867 Multicellular Cancer Spheroids as an in Vitro Model for Localized Hyperthermia Study
Authors: Kamila Dus-Szachniewicz, Artur Bednarkiewicz, Katarzyna Gdesz-Birula, Slawomir Drobczynski
Abstract:
In modern oncology hyperthermia (HT) is defined as a controlled tumor heating. HT treatment temperatures range between 40–48 °C and can selectively damage heat-sensitive cancer cells or limit their further growth, usually with minimal injury to healthy tissues. Despite many advantages, conventional whole-body and regional hyperthermia have clinically relevant side effects, including cardiac and vascular disorders. Additionally, the lack of accessibility of deep-seated tumor sites and impaired targeting micrometastases renders HT less effective. It is believed that above disadvantages can significantly overcome by the application of biofunctionalized microparticles, which can specifically target tumor sites and become activated by an external stimulus to provide a sufficient cellular response. In our research, the unique optical tweezers system have enabled capturing the silica microparticles, primary cells and tumor spheroids in highly controllable and reproducible environment to study the impact of localized heat stimulation on normal and pathological cell and within multicellular tumor spheroid. High throughput spheroid model was introduced to better mimic the response to HT treatment on tumors in vivo. Additionally, application of local heating of tumor spheroids was performed in strictly controlled conditions resembling tumor microenvironment (temperature, pH, hypoxia, etc.), in response to localized and nonhomogeneous hyperthermia in the extracellular matrix, which promotes tumor progression and metastatic spread. The lack of precise control over these well- defined parameters in basic research leads to discrepancies in the response of tumor cells to the new treatment strategy in preclinical animal testing. The developed approach enables also sorting out subclasses of cells, which exhibit partial or total resistance to therapy, in order to understand fundamental aspects of the resistance shown by given tumor cells in response to given therapy mode and conditions. This work was funded by the National Science Centre (NCN, Poland) under grant no. UMO-2017/27/B/ST7/01255.Keywords: cancer spheroids, hyperthermia, microparticles, optical tweezers
Procedia PDF Downloads 12815866 Lessons Learned from Implementation of Remote Pregnant and Newborn Care Service for Vulnerable Women and Children During COVID-19 and Political Crisis in Myanmar
Authors: Wint Wint Thu, Htet Ko Ko Win, Myat Mon San, Zaw Lin Tun, Nandar Than Aye, Khin Nyein Myat, Hayman Nyo Oo, Nay Aung Lin, Kusum Thapa, Kyaw Htet Aung
Abstract:
Background: In Myanmar, the intense political instability happened to start in Feb-2021, while the COVID-19 pandemic waves are also threatening the public health system, which subsequently led to severe health sector crisis, including difficulties in accessing maternal and newborn health care for vulnerable women and children. The Remote Pregnant and Newborn Care (RPNC) uses a telehealth approach United States Agency for International Development (USAID)-funded Essential Health Project. Implementation: The Remote Pregnant and Newborn Care (RPNC) service has adapted to the MNCH needs of vulnerable pregnant women and was implemented to mitigate the risk of limited access to essential quality MNH care in Yangon, Myanmar, under women, and the project trained 13 service providers on a telehealth care package for pregnancy and newborn developed Jhpiego to ensure understanding of evidence-based MNCH care practices. The phone numbers of the pregnant women were gathered through the preexisting and functioning community volunteers, who reach the most vulnerable pregnant women in the project's targeted area. A total of 212 pregnant women have been reached by service providers for RPNC during the implementation period. The trained service providers offer quality antenatal and postnatal care, including newborn care, via telephone calls. It includes 24/7 incoming calls and time-allotted outgoing calls to the pregnant women during antenatal and postnatal periods, including the newborn care. The required data were collected daily in time with the calls, and the quality of the medical services is made assured with the track of the calls, ensuring data privacy and patient confidentiality. Lessons learned: The key lessons are 1) cost-effectiveness: RPNC service could reduce out of pocket expenditure of pregnant women as it only costs 1.6 United States dollars (USD) per one telehealth call while it costs 8 to 10 USD per one time in-person care service at private service providers, including transportation cost, 2) network of care: telehealth call could not replace the in-person antenatal and postnatal care services, and integration of telehealth calls with in-person care by local healthcare providers with the support of the community is crucial for accessibility to essential MNH services by poor and vulnerable women, and 3) sharing information on health access points: most of the women seem to have financial barriers in accessing private health facilities while public health system collapse and telehealthcare could provide information on low-cost facilities and connect women to relevant health facilities. These key lessons are important for future efforts regarding the implementation of remote pregnancy and newborn care in Myanmar, especially during the political crisis and COVID-19 pandemic situation.Keywords: telehealth, accessibility, maternal care, newborn care
Procedia PDF Downloads 9015865 A Multilevel Approach for Stroke Prediction Combining Risk Factors and Retinal Images
Authors: Jeena R. S., Sukesh Kumar A.
Abstract:
Stroke is one of the major reasons of adult disability and morbidity in many of the developing countries like India. Early diagnosis of stroke is essential for timely prevention and cure. Various conventional statistical methods and computational intelligent models have been developed for predicting the risk and outcome of stroke. This research work focuses on a multilevel approach for predicting the occurrence of stroke based on various risk factors and invasive techniques like retinal imaging. This risk prediction model can aid in clinical decision making and help patients to have an improved and reliable risk prediction.Keywords: prediction, retinal imaging, risk factors, stroke
Procedia PDF Downloads 29415864 Two Kinds of Self-Oscillating Circuits Mechanically Demonstrated
Authors: Shiang-Hwua Yu, Po-Hsun Wu
Abstract:
This study introduces two types of self-oscillating circuits that are frequently found in power electronics applications. Special effort is made to relate the circuits to the analogous mechanical systems of some important scientific inventions: Galileo’s pendulum clock and Coulomb’s friction model. A little touch of related history and philosophy of science will hopefully encourage curiosity, advance the understanding of self-oscillating systems and satisfy the aspiration of some students for scientific literacy. Finally, the two self-oscillating circuits are applied to design a simple class-D audio amplifier.Keywords: self-oscillation, sigma-delta modulator, pendulum clock, Coulomb friction, class-D amplifier
Procedia PDF Downloads 34515863 A New Modification of Nonlinear Conjugate Gradient Coefficients with Global Convergence Properties
Authors: Ahmad Alhawarat, Mustafa Mamat, Mohd Rivaie, Ismail Mohd
Abstract:
Conjugate gradient method has been enormously used to solve large scale unconstrained optimization problems due to the number of iteration, memory, CPU time, and convergence property, in this paper we find a new class of nonlinear conjugate gradient coefficient with global convergence properties proved by exact line search. The numerical results for our new βK give a good result when it compared with well-known formulas.Keywords: conjugate gradient method, conjugate gradient coefficient, global convergence
Procedia PDF Downloads 45015862 Non-Destructive Inspection for Tunnel Lining Concrete with Small Void by Using Ultrasonic
Authors: Yasuyuki Nabeshima
Abstract:
Many tunnels which have been constructed since more than 50 years were existing in Japan. Lining concrete in these tunnels have many problems such as crack, flacking and void. Inner void between lining concrete and rock was very hard to find by outside visual check and hammering test. In this paper, non-destructive inspection by using ultrasonic was applied to investigate inner void. A model concrete with inner void was used as specimen and ultrasonic inspection was applied to specify the location and the size of void. As a result, ultrasonic inspection could accurately find the inner void.Keywords: tunnel, lining concrete, void, non-destructive inspection, ultrasonic
Procedia PDF Downloads 19915861 Ruta graveolens Fingerprints Obtained with Reversed-Phase Gradient Thin-Layer Chromatography with Controlled Solvent Velocity
Authors: Adrian Szczyrba, Aneta Halka-Grysinska, Tomasz Baj, Tadeusz H. Dzido
Abstract:
Since prehistory, plants were constituted as an essential source of biologically active substances in folk medicine. One of the examples of medicinal plants is Ruta graveolens L. For a long time, Ruta g. herb has been famous for its spasmolytic, diuretic, or anti-inflammatory therapeutic effects. The wide spectrum of secondary metabolites produced by Ruta g. includes flavonoids (eg. rutin, quercetin), coumarins (eg. bergapten, umbelliferone) phenolic acids (eg. rosmarinic acid, chlorogenic acid), and limonoids. Unfortunately, the presence of produced substances is highly dependent on environmental factors like temperature, humidity, or soil acidity; therefore standardization is necessary. There were many attempts of characterization of various phytochemical groups (eg. coumarins) of Ruta graveolens using the normal – phase thin-layer chromatography (TLC). However, due to the so-called general elution problem, usually, some components remained unseparated near the start or finish line. Therefore Ruta graveolens is a very good model plant. Methanol and petroleum ether extract from its aerial parts were used to demonstrate the capabilities of the new device for gradient thin-layer chromatogram development. The development of gradient thin-layer chromatograms in the reversed-phase system in conventional horizontal chambers can be disrupted by problems associated with an excessive flux of the mobile phase to the surface of the adsorbent layer. This phenomenon is most likely caused by significant differences between the surface tension of the subsequent fractions of the mobile phase. An excessive flux of the mobile phase onto the surface of the adsorbent layer distorts the flow of the mobile phase. The described effect produces unreliable, and unrepeatable results, causing blurring and deformation of the substance zones. In the prototype device, the mobile phase solution is delivered onto the surface of the adsorbent layer with controlled velocity (by moving pipette driven by 3D machine). The delivery of the solvent to the adsorbent layer is equal to or lower than that of conventional development. Therefore chromatograms can be developed with optimal linear mobile phase velocity. Furthermore, under such conditions, there is no excess of eluent solution on the surface of the adsorbent layer so the higher performance of the chromatographic system can be obtained. Directly feeding the adsorbent layer with eluent also enables to perform convenient continuous gradient elution practically without the so-called gradient delay. In the study, unique fingerprints of methanol and petroleum ether extracts of Ruta graveolens aerial parts were obtained with stepwise gradient reversed-phase thin-layer chromatography. Obtained fingerprints under different chromatographic conditions will be compared. The advantages and disadvantages of the proposed approach to chromatogram development with controlled solvent velocity will be discussed.Keywords: fingerprints, gradient thin-layer chromatography, reversed-phase TLC, Ruta graveolens
Procedia PDF Downloads 28515860 Parametric Study for Obtaining the Structural Response of Segmental Tunnels in Soft Soil by Using No-Linear Numerical Models
Authors: Arturo Galván, Jatziri Y. Moreno-Martínez, Israel Enrique Herrera Díaz, José Ramón Gasca Tirado
Abstract:
In recent years, one of the methods most used for the construction of tunnels in soft soil is the shield-driven tunneling. The advantage of this construction technique is that it allows excavating the tunnel while at the same time a primary lining is placed, which consists of precast segments. There are joints between segments, also called longitudinal joints, and joints between rings (called as circumferential joints). This is the reason because of this type of constructions cannot be considered as a continuous structure. The effect of these joints influences in the rigidity of the segmental lining and therefore in its structural response. A parametric study was performed to take into account the effect of different parameters in the structural response of typical segmental tunnels built in soft soil by using non-linear numerical models based on Finite Element Method by means of the software package ANSYS v. 11.0. In the first part of this study, two types of numerical models were performed. In the first one, the segments were modeled by using beam elements based on Timoshenko beam theory whilst the segment joints were modeled by using inelastic rotational springs considering the constitutive moment-rotation relation proposed by Gladwell. In this way, the mechanical behavior of longitudinal joints was simulated. On the other hand for simulating the mechanical behavior of circumferential joints elastic springs were considered. As well as, the stability given by the soil was modeled by means of elastic-linear springs. In the second type of models, the segments were modeled by means of three-dimensional solid elements and the joints with contact elements. In these models, the zone of the joints is modeled as a discontinuous (increasing the computational effort) therefore a discrete model is obtained. With these contact elements the mechanical behavior of joints is simulated considering that when the joint is closed, there is transmission of compressive and shear stresses but not of tensile stresses and when the joint is opened, there is no transmission of stresses. This type of models can detect changes in the geometry because of the relative movement of the elements that form the joints. A comparison between the numerical results with two types of models was carried out. In this way, the hypothesis considered in the simplified models were validated. In addition, the numerical models were calibrated with (Lab-based) experimental results obtained from the literature of a typical tunnel built in Europe. In the second part of this work, a parametric study was performed by using the simplified models due to less used computational effort compared to complex models. In the parametric study, the effect of material properties, the geometry of the tunnel, the arrangement of the longitudinal joints and the coupling of the rings were studied. Finally, it was concluded that the mechanical behavior of segment and ring joints and the arrangement of the segment joints affect the global behavior of the lining. As well as, the effect of the coupling between rings modifies the structural capacity of the lining.Keywords: numerical models, parametric study, segmental tunnels, structural response
Procedia PDF Downloads 22315859 Breaching Treaty Obligations of the Rome Statute of the International Criminal Court: The Case of South Africa
Authors: David Abrahams
Abstract:
In October 2016 South Africa deposited its ‘instrument of withdrawal’ from the Rome Statute of the International Criminal Court, with the Secretary-General of the United Nations. The Rome Statute is the founding document of the treaty-based International Criminal Court (ICC). The ICC has jurisdiction to hear cases where crimes against humanity, war crimes and genocide have been committed, on the basis of individual criminal responsibility. It is therefore not surprising that one of the ICCs mandates is to ensure that the sufferings, due to gross human rights violations towards the civilian population is, in principle, brought to an end by punishing those individuals responsible, thus providing justice to the victims. The ICC is unable to effectively fulfill its mandate and thus depends, in part on the willingness of states to assist the Court in its functions. This requires states to ratify the Statute and to domesticate its provisions, depending on whether it is a monist or dualist state. South Africa ratified the Statute in November 2000, and domesticated the Statute in 2002 by virtue of the Implementation of the Rome Statute of the International Criminal Court Act 27 of 2002. South Africa thus remains under an obligation to cooperate with the ICC until the final date of withdrawal, which is October 2017. An AU Summit was hosted by South Africa during June 2015. Omar Al-Bashir, whom the prosecutor of the ICC has indicted on two separate occasions, was invited to the summit. South Africa made an agreement with the AU that it will honour its obligations in terms of its Diplomatic and Immunities Privileges Act of 2001, by granting immunity to all heads of state, including that of Sudan. This decision by South Africa has raised a plethora of questions regarding the status and hierarchy of international laws versus regional laws versus domestic laws. In particular, this paper explores whether a state’s international law treaty obligations may be suspended in favour of, firstly, regional peace (thus safeguarding the security of the civilian population against further atrocities and other gross violations of human rights), and secondly, head of state immunity. This paper also reflects on the effectiveness of the trias politca in South Africa in relation the manner in which South African courts have confirmed South Africa’s failure in fulfilling its obligations in terms of the Rome Statute. A secondary question which will also be explored, is whether the Rome Statute is currently an effective tool in dealing with gross violations of human rights, particularly in a regional African context, given the desire by a number of African states currently party to the Statute, to engage in a mass exodus from the Statute. Finally, the paper concludes with a proposal that there can be no justice for victims of gross human rights violations unless states are serious in playing an instrumental role in bringing an end to impunity in Africa, and that withdrawing from the ICC without an alternative, effective system in place, will simply perpetuate impunity.Keywords: African Union, diplomatic immunity, impunity, international criminal court, South Africa
Procedia PDF Downloads 52015858 The Implementation of Inclusive Education in Collaboration between Teachers of Special Education Classes and Regular Classes in a Preschool
Authors: Chiou-Shiue Ko
Abstract:
As is explicitly stipulated in Article 7 of the Enforcement Rules of the Special Education Act as amended in 1998, "in principle, children with disabilities should be integrated with normal children for preschool education". Since then, all cities and counties have been committed to promoting preschool inclusive education. The Education Department, New Taipei City Government, has been actively recruiting advisory groups of professors to assist in the implementation of inclusive education in preschools since 2001. Since 2011, the author of this study has been guiding Preschool Rainbow to implement inclusive education. Through field observations, meetings, and teaching demonstration seminars, this study explored the process of how inclusive education has been successfully implemented in collaboration with teachers of special education classes and regular classes in Preschool Rainbow. The implementation phases for inclusive education in a single academic year include the following: 1) Preparatory stage. Prior to implementation, teachers in special education and regular classes discuss ways of conducting inclusive education and organize reading clubs to read books related to curriculum modifications that integrate the eight education strategies, early treatment and education, and early childhood education programs to enhance their capacity to implement and compose teaching plans for inclusive education. In addition to the general objectives of inclusive education, the objective of inclusive education for special children is also embedded into the Individualized Education Program (IEP). 2) Implementation stage. Initially, a promotional program for special education is implemented for the children to allow all the children in the preschool to understand their own special qualities and those of special children. After the implementation of three weeks of reverse inclusion, the children in the special education classes are put into groups and enter the regular classes twice a week to implement adjustments to their inclusion in the learning area and the curriculum. In 2013, further cooperation was carried out with adjacent hospitals to perform development screening activities for the early detection of children with developmental delays. 3) Review and reflection stage. After the implementation of inclusive education, all teachers in the preschool are divided into two groups to record their teaching plans and the lessons learned during implementation. The effectiveness of implementing the objective of inclusive education is also reviewed. With the collaboration of all teachers, in 2015, Preschool Rainbow won New Taipei City’s “Preschool Light” award as an exceptional model for inclusive education. Its model of implementing inclusive education can be used as a reference for other preschools.Keywords: collaboration, inclusive education, preschool, teachers, special education classes, regular classes
Procedia PDF Downloads 42115857 Learning Fashion Construction and Manufacturing Methods from the Past: Cultural History and Genealogy at the Middle Tennessee State University Historic Clothing Collection
Authors: Teresa B. King
Abstract:
In the millennial age, with more students desiring a fashion major yet fewer having sewing and manufacturing knowledge, this increases demand on academicians to adequately educate. While fashion museums have a prominent place for historical preservation, the need for apparel education via working collections of handmade or mass manufactured apparel is lacking in most universities in the United States, especially in the Southern region. Created in 1988, Middle Tennessee State University’s historic clothing collection provides opportunities to study apparel construction methods throughout history, to compare and apply to today’s construction and manufacturing methods, as well as to learn the cyclical nature/importance of historic styles on current and upcoming fashion. In 2019, a class exercise experiment was implemented for which students researched their family genealogy using Ancestry.com, identified the oldest visual media (photographs, etc.) available, and analyzed the garment represented in said media. The student then located a comparable garment in the historic collection and evaluated the construction methods of the ancestor’s time period. A class 'fashion' genealogy tree was created and mounted for public viewing/education. Results of this exercise indicated that student learning increased due to the 'personal/familial connection' as it triggered more interest in historical garments as related to the student’s own personal culture. Students better identified garments regarding the historical time period, fiber content, fabric, and construction methods utilized, thus increasing learning and retention. Students also developed increased learning and recognition of custom construction methods versus current mass manufacturing techniques, which impact today’s fashion industry. A longitudinal effort will continue with the growth of the historic collection and as students continue to utilize the historic clothing collection.Keywords: ancestry, clothing history, fashion history, genealogy, historic fashion museum collection
Procedia PDF Downloads 13015856 Coffee Consumption Has No Acute Effects on Glucose Metabolism in Healthy Men: A Randomized Crossover Clinical Trial
Authors: Caio E. G. Reis, Sara Wassell, Adriana L. Porto, Angélica A. Amato, Leslie J. C. Bluck, Teresa H. M. da Costa
Abstract:
Background: Multiple epidemiologic studies have consistently reported association between increased coffee consumption and a lowered risk of Type 2 Diabetes Mellitus. However, the mechanisms behind this finding have not been fully elucidated. Objective: We investigate the effect of coffee (caffeinated and decaffeinated) on glucose effectiveness and insulin sensitivity using the stable isotope minimal model protocol with oral glucose administration in healthy men. Design: Fifteen healthy men underwent 5 arms randomized crossover single-blinding (researchers) clinical trial. They consumed decaffeinated coffee, caffeinated coffee (with and without sugar), and controls – water (with and without sugar) followed 1 hour by an oral glucose tolerance test (75 g of available carbohydrate) with intravenous labeled dosing interpreted by the two compartment minimal model (225 minutes). One-way ANOVA with Bonferroni adjustment were used to compare the effects of the tested beverages on glucose metabolism parameters. Results: Decaffeinated coffee resulted in 29% and 85% higher insulin sensitivity compared with caffeinated coffee and water, respectively, and the caffeinated coffee showed 15% and 60% higher glucose effectiveness compared with decaffeinated coffee and water, respectively. However, these differences were not significant (p > 0.10). In overall analyze (0 – 225 min) there were no significant differences on glucose effectiveness, insulin sensitivity, and glucose and insulin area under the curve between the groups. The beneficial effects of coffee did not seem to act in the short-term (hours) on glucose metabolism parameters mainly on insulin sensitivity indices. The benefits of coffee consumption occur in the long-term (years) as has been shown in the reduction of Type 2 Diabetes Mellitus risk in epidemiological studies. The clinical relevance of the present findings is that there is no need to avoid coffee as the drink choice for healthy people. Conclusions: The findings of this study demonstrate that the consumption of caffeinated and decaffeinated coffee with or without sugar has no acute effects on glucose metabolism in healthy men. Further researches, including long-term interventional studies, are needed to fully elucidate the mechanisms behind the coffee effects on reduced risk for Type 2 Diabetes Mellitus.Keywords: coffee, diabetes mellitus type 2, glucose, insulin
Procedia PDF Downloads 42815855 Management of Myofascial Temporomandibular Disorder in Secondary Care: A Quality Improvement Project
Authors: Rishana Bilimoria, Selina Tang, Sajni Shah, Marianne Henien, Christopher Sproat
Abstract:
Temporomandibular disorders (TMD) may affect up to a third of the general population, and there is evidence demonstrating the majority of Myofascial TMD cases improve after education and conservative measures. In 2015 our department implemented a modified care pathway for myofascial TMD patients in an attempt to improve the patient journey. This involved the use of an interactive group therapy approach to deliver education, reinforce conservative measures and promote self-management. Patient reported experience measures from the new group clinic revealed 71% patient satisfaction. This service is efficient in improving aspects of health status while reducing health-care costs and redistributing clinical time. Since its’ establishment, 52 hours of clinical time, resources and funding have been redirected effectively. This Quality Improvement Project was initiated because it was felt that this new service was being underutilised by our surgical teams. The ‘Plan-Do-Study-Act cycle’ (PDSA) framework was employed to analyse utilisation of the service: The ‘plan’ stage involved outlining our aims: to raise awareness amongst clinicians of the unified care pathway and to increase referral to this clinic. The ‘do’ stage involved collecting data from a sample of 96 patients over 4 month period to ascertain the proportion of Myofascial TMD patients who were correctly referred to the designated clinic. ‘Suitable’ patients who weren’t referred were identified. The ‘Study’ phase involved analysis of results, which revealed that 77% of suitable patients weren’t referred to the designated clinic. They were reviewed on other clinics, which are often overbooked, or managed by junior staff members. This correlated with our original prediction. Barriers to referral included: lack of awareness of the clinic, individual consultant treatment preferences and patient, reluctance to be referred to a ‘group’ clinic. The ‘Act’ stage involved presenting our findings to the team at a clinical governance meeting. This included demonstration of the clinical effectiveness of the care-pathway and explaining the referral route and criteria. In light of the evaluation results, it was decided to keep the group clinic and maximize utilisation. The second cycle of data collection following these changes revealed that of 66 Myofascial TMD patients over a 4 month period, only 9% of suitable patients were not seen via the designated pathway; therefore this QIP was successful in meeting the set objectives. Overall, employing the PDSA cycle in this QIP resulted in appropriate utilisation of the modified care pathway for patients with myofascial TMD in Guy’s Oral Surgery Department. In turn, this leads to high patient satisfaction with the service and effectively redirected 52 hours of clinical time. It permitted adoption of a collaborative working style with oral surgery colleagues to investigate problems, identify solutions, and collectively raise standards of clinical care to ensure we adopt a unified care pathway in secondary care management of Myofascial TMD patients.Keywords: myofascial, quality Improvement, PDSA, TMD
Procedia PDF Downloads 13515854 Universality and Synchronization in Complex Quadratic Networks
Authors: Anca Radulescu, Danae Evans
Abstract:
The relationship between a network’s hardwiring and its emergent dynamics are central to neuroscience. We study the principles of this correspondence in a canonical setup (in which network nodes exhibit well-studied complex quadratic dynamics), then test their universality in biological networks. By extending methods from discrete dynamics, we study the effects of network connectivity on temporal patterns, encapsulating long-term behavior into the rich topology of network Mandelbrot sets. Then elements of fractal geometry can be used to predict and classify network behavior.Keywords: canonical model, complex dynamics, dynamic networks, fractals, Mandelbrot set, network connectivity
Procedia PDF Downloads 29915853 Modelling Strategy Planning in Multi Business Companies
Authors: Gelareh Changizi, Mahsa Khajavi, Ladan Shahhosseini
Abstract:
Corporate-level strategy, or simply ‘parent strategy’, is a topic that has received much attention since the very early days of the strategic planning field. Since the multi level enterprises have different sub enterprises which deal with different business environments, we cannot define the same strategic perspective for all of them. Therefore, the determination of a perspective to manage and deal with affiliates of such enterprises is the main challenge. The parent strategy in mother enterprises' level has been analyzed in this research. A case study has been carried to comprehensively describe the proposed model.Keywords: parent strategy, multi-business companies, performance evaluation, lifecycle
Procedia PDF Downloads 36115852 A Journey to the Past: Hoşap Castle in Van
Authors: Muhammet Kurucu
Abstract:
Hoşap Castle, located in Gürpınar, Van, is one of the most important symbols of the city because it hosted sacred memories of its time. Besides the location and construction features of Güzelsu, in resort city of Van, Hoşap Castle is a great place with an architecture consisting of an outer fortress and the inner fortress. It is one of the Ottoman castles and was built in the 17th century by Sarı Süleyman who was known as bey of Mahmudi. Although some parts of Hoşap Castle have been destroyed by natural disasters, it has survived until today without total collapse and most places with excavations are revealed. In this study, present condition of the Hoşap Castle is observed and introduced briefly.Keywords: Güzelsu, Hoşap Castle, natural disasters, restoration, Van
Procedia PDF Downloads 26915851 Characters of Developing Commercial Employment Sub-Centres and Employment Density in Ahmedabad City
Authors: Bhaumik Patel, Amit Gotecha
Abstract:
Commercial centres of different hierarchy and sizes play a vital role in the growth and development of the city. Economic uncertainty and demand for space leads to more urban sprawl and emerging more commercial spaces. The study was focused on the understanding of various indicators affecting the commercial development that can help to solve many issues related to commercial urban development and can guide for future employment growth centre development, Accessibility, Infrastructure, Planning and development regulations and Market forces. The aim of the study was to review characteristics and identifying employment density of Commercial Employment Sub-centres by achieving objectives Understanding various employment sub-centres, Identifying characteristics and deriving behaviour of employment densities and Evaluating and comparing employment sub-centres for the Ahmedabad city. Commercial employment sub-centres one in old city (Kalupur), second in highly developed commercial (C.G.road-Ashram road) and third in the latest developing commercial area (Prahladnagar) were identified by distance from city centre, Land use diversity, Access to Major roads and Public transport, Population density in proximity, Complimentary land uses in proximity and Land price. Commercial activities were categorised into retail, wholesale and service sector and sub categorised into various activities. From the study, Time period of establishment of the unit is a critical parameter for commercial activity, building height, and land-use diversity. Employment diversity is also one parameter for the commercial centre. The old city has retail, wholesale and trading and higher commercial density concerning units and employment both. Prahladnagar area functioned as commercial due to market pressure and developed as more units rather than a requirement. Employment density is higher in the centre of the city, as far as distance increases from city centre employment density and unit density decreases. Characters of influencing employment density and unit density are distance from city centre, development type, establishment time period, building density, unit density, public transport accessibility and road connectivity.Keywords: commercial employment sub-centres, employment density, employment diversity, unit density
Procedia PDF Downloads 13015850 Pharmacokinetics and Safety of Pacritinib in Patients with Hepatic Impairment and Healthy Volunteers
Authors: Suliman Al-Fayoumi, Sherri Amberg, Huafeng Zhou, Jack W. Singer, James P. Dean
Abstract:
Pacritinib is an oral kinase inhibitor with specificity for JAK2, FLT3, IRAK1, and CSF1R. In clinical studies, pacritinib was well tolerated with clinical activity in patients with myelofibrosis. The most frequent adverse events (AEs) observed with pacritinib are gastrointestinal (diarrhea, nausea, and vomiting; mostly grade 1-2 in severity) and typically resolve within 2 weeks. A human ADME mass balance study demonstrated that pacritinib is predominantly cleared via hepatic metabolism and biliary excretion (>85% of administered dose). The major hepatic metabolite identified, M1, is not thought to materially contribute to the pharmacological activity of pacritinib. Hepatic diseases are known to impair hepatic blood flow, drug-metabolizing enzymes, and biliary transport systems and may affect drug absorption, disposition, efficacy, and toxicity. This phase 1 study evaluated the pharmacokinetics (PK) and safety of pacritinib and the M1 metabolite in study subjects with mild, moderate, or severe hepatic impairment (HI) and matched healthy subjects with normal liver function to determine if pacritinib dosage adjustments are necessary for patients with varying degrees of hepatic insufficiency. Study participants (aged 18-85 y) were enrolled into 4 groups based on their degree of HI as defined by Child-Pugh Clinical Assessment Score: mild (n=8), moderate (n=8), severe (n=4), and healthy volunteers (n=8) matched for age, BMI, and sex. Individuals with concomitant renal dysfunction or progressive liver disease were excluded. A single 400 mg dose of pacritinib was administered to all participants. Blood samples were obtained for PK evaluation predose and at multiple time points postdose through 168 h. Key PK parameters evaluated included maximum plasma concentration (Cmax), time to Cmax (Tmax), area under the plasma concentration time curve (AUC) from hour zero to last measurable concentration (AUC0-t), AUC extrapolated to infinity (AUC0-∞), and apparent terminal elimination half-life (t1/2). Following treatment, pacritinib was quantifiable for all study participants at 1 h through 168 h postdose. Systemic pacritinib exposure was similar between healthy volunteers and individuals with mild HI. However, there was a significant difference between those with moderate and severe HI and healthy volunteers with respect to peak concentration (Cmax) and plasma exposure (AUC0-t, AUC0-∞). Mean Cmax decreased by 47% and 57% respectively in participants with moderate and severe HI vs matched healthy volunteers. Similarly, mean AUC0-t decreased by 36% and 45% and mean AUC0-∞ decreased by 46% and 48%, respectively in individuals with moderate and severe HI vs healthy volunteers. Mean t1/2 ranged from 51.5 to 74.9 h across all groups. The variability on exposure ranged from 17.8% to 51.8% across all groups. Systemic exposure of M1 was also significantly decreased in study participants with moderate or severe HI vs. healthy participants and individuals with mild HI. These changes were not significantly dissimilar from the inter-patient variability in these parameters observed in healthy volunteers. All AEs were grade 1-2 in severity. Diarrhea and headache were the only AEs reported in >1 participant (n=4 each). Based on these observations, it is unlikely that dosage adjustments would be warranted in patients with mild, moderate, or severe HI treated with pacritinib.Keywords: pacritinib, myelofibrosis, hepatic impairment, pharmacokinetics
Procedia PDF Downloads 29515849 Case-Based Reasoning for Modelling Random Variables in the Reliability Assessment of Existing Structures
Authors: Francesca Marsili
Abstract:
The reliability assessment of existing structures with probabilistic methods is becoming an increasingly important and frequent engineering task. However probabilistic reliability methods are based on an exhaustive knowledge of the stochastic modeling of the variables involved in the assessment; at the moment standards for the modeling of variables are absent, representing an obstacle to the dissemination of probabilistic methods. The framework according to probability distribution functions (PDFs) are established is represented by the Bayesian statistics, which uses Bayes Theorem: a prior PDF for the considered parameter is established based on information derived from the design stage and qualitative judgments based on the engineer past experience; then, the prior model is updated with the results of investigation carried out on the considered structure, such as material testing, determination of action and structural properties. The application of Bayesian statistics arises two different kind of problems: 1. The results of the updating depend on the engineer previous experience; 2. The updating of the prior PDF can be performed only if the structure has been tested, and quantitative data that can be statistically manipulated have been collected; performing tests is always an expensive and time consuming operation; furthermore, if the considered structure is an ancient building, destructive tests could compromise its cultural value and therefore should be avoided. In order to solve those problems, an interesting research path is represented by investigating Artificial Intelligence (AI) techniques that can be useful for the automation of the modeling of variables and for the updating of material parameters without performing destructive tests. Among the others, one that raises particular attention in relation to the object of this study is constituted by Case-Based Reasoning (CBR). In this application, cases will be represented by existing buildings where material tests have already been carried out and an updated PDFs for the material mechanical parameters has been computed through a Bayesian analysis. Then each case will be composed by a qualitative description of the material under assessment and the posterior PDFs that describe its material properties. The problem that will be solved is the definition of PDFs for material parameters involved in the reliability assessment of the considered structure. A CBR system represent a good candi¬date in automating the modelling of variables because: 1. Engineers already draw an estimation of the material properties based on the experience collected during the assessment of similar structures, or based on similar cases collected in literature or in data-bases; 2. Material tests carried out on structure can be easily collected from laboratory database or from literature; 3. The system will provide the user of a reliable probabilistic description of the variables involved in the assessment that will also serve as a tool in support of the engineer’s qualitative judgments. Automated modeling of variables can help in spreading probabilistic reliability assessment of existing buildings in the common engineering practice, and target at the best intervention and further tests on the structure; CBR represents a technique which may help to achieve this.Keywords: reliability assessment of existing buildings, Bayesian analysis, case-based reasoning, historical structures
Procedia PDF Downloads 33515848 The Effects of Orally Administered Bacillus Coagulans and Inulin on Prevention and Progression of Rheumatoid Arthritis in Rats
Authors: Khadijeh Abhari, Seyed Shahram Shekarforoush, Saeid Hosseinzadeh
Abstract:
Probiotics have been considered as an approach to treat and prevent a wide range of inflammatory diseases. The spore forming probiotic strain Bacillus coagulans has demonstrated anti-inflammatory and immune-modulating effects in both animals and humans. The prebiotic, inulin, also potentially affects the immune system as a result of the change in the composition or fermentation profile of the gastrointestinal microbiota. An in vivo trial was conducted to evaluate the effects of probiotic B. coagulans, and inulin, either separately or in combination, on down regulate immune responses and progression of rheumatoid arthritis using induced arthritis rat model. Forty-eight male Wistar rats were randomly divided into 6 groups and fed as follow: 1) control: Normal healthy rats fed by standard diet, 2) Disease control (RA): Arthritic induced (RA) rats fed by standard diet, 3) Prebiotic (PRE): RA+ 5% w/w long chain inulin, 4) Probiotic (PRO): RA+ 109 spores/day B. coagulans by orogastric gavage, 5) Synbiotic (SYN): RA+ 5% w/w long chain inulin and 109 spores/day B. coagulans and 6) Treatment control: (INDO): RA+ 3 mg/kg/day indomethacin by orogastric gavage. Feeding with mentioned diets started on day 0 and continued to the end of study. On day 14, rats were injected with complete Freund’s adjuvant (CFA) to induce arthritis. Arthritis activity was evaluated by biochemical parameters and paw thickness. Biochemical assay for Fibrinogen (Fn), Serum Amyloid A (SAA), TNF-α and Alpha-1-acid glycoprotein (α1AGp) was performed on day 21, 28 and 35 (1, 2 and 3 weeks post RA induction). Pretreatment with PRE, PRO and SYN diets significantly inhibit SAA and Fn production in arthritic rats (P < 0.001). A significant decrease in production of pro-inflammatory cytokines, TNF-α, was seen in PRE, PRO and SYN groups (P < 0.001) which was similar to the effect of the anti-inflammatory drug Indomethacin. Further, there were no significant anti-inflammatory effects observed following different treatments using α1AGp as a RA indicator. Pretreatment with all supplied diets significantly inhibited the development of paw swelling induced by CFA (P < 0.001). Conclusion: Results of this study support that oral intake of probiotic B. coagulans and inulin are able to improve biochemical and clinical parameters of induced RA in rat.Keywords: rheumatoid arthritis, bacillus coagulans, inulin, animal model
Procedia PDF Downloads 348