Search results for: real time model

Authors: Godfrey Omulo, Regina Birner, Karlheinz Koller, Thomas Daum

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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

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Authors: Arturo Galván, Jatziri Y. Moreno-Martínez, Israel Enrique Herrera Díaz, José Ramón Gasca Tirado

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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

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Authors: Khadijeh Abhari, Seyed Shahram Shekarforoush, Saeid Hosseinzadeh

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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

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Authors: Hemant Kumar, Nilendu Das

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A study based on ANN structure gives us the information to predict the size of the future in realizing a past event. ANN, IMD (Indian meteorological department) data and remote sensing were used to enable a number of parameters for calculating the size that may occur in the future. A threshold selected specifically above the high-frequency harvest reached the area during the selected seismic activity. In the field of human and local biodiversity it remains to obtain the right parameter compared to the frequency of impact. But during the study the assumption is that predicting seismic activity is a difficult process, not because of the parameters involved here, which can be analyzed and funded in research activity.

Keywords: ANN, Bayesion class, earthquakes, IMD

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Authors: Rehan Ullah

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The primary purpose of the study is to observe the relationship that exists between the organizational information technology (IT) capabilities and the organizational performance in China and Pakistan. Nations like China and Pakistan utilize modern techno-how to enhance their production endeavors. Therefore, making a wide-ranging comparison of the manufacturing services between China and Pakistan was chosen due to numerous reasons. One reason for carrying out this comparison is to determine how IT of the two countries enhances organizational competency on small and medium-sized manufacturing enterprises (SMEs). The study hypothesized that organizational IT capabilities (IT infrastructure, IT competence) have a positive influence on organizational performance and the strategic benefits of IT have a mediating effect on the relationship between IT capability and organizational performance. To investigate the relationship between IT capabilities and organizational performance, surveys were sent to managers of small, medium-sized manufacturing organizations located in the southwestern region, Sichuan province of China, and Pakistani companies, which are located in Islamabad, Lahore, and Karachi. These cities were selected as typical representatives of each country. Organizational performance has been measured in terms of profitability, organizational success, growth, market share, and innovativeness. Out of 400 surveys distributed to different manufacturing organizations, 303 usable and valid responses were received that are analyzed in this research. The data were examined using SPSS and Smart PLS computer software. The results of the study, including the descriptive statistics of each variable, are used. The outer model has been measured with considerations to content validity, discriminant validity, and convergent validity. The path coefficients among the constructs were also computed when analyzing the structural model using the bootstrapping technique. The analysis of data from both China and Pakistan yields an identical but unique result. The results show that IT infrastructure, IT competence, strategic benefits of IT are all correlated to the performance of the organizations. Moreover, strategic benefits of IT have been proved to mediate the relationship between IT capabilities and organization performance. The author, concerning the role of IT on the performance of an organization, highlights the different aspects as well as its benefits in an organization. The overall study concludes several implications for both managers and academicians. It also provides the limitations of the study and offers recommendations for future studies and practice.

Keywords: organizational performance, IT capabilities, IT infrastructure, IT competence, strategic benefits of IT, China, Pakistan

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Authors: Yusuf Yilmaz, Gamze Gediz Ilis

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

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

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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

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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

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Authors: Ahmad Alhawarat, Mustafa Mamat, Mohd Rivaie, Ismail Mohd

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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

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Authors: Tess Howard, Lily Owens, Maneesha De Silva, Russell Hodgson

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Purpose: This study aims to evaluate the cost-effectiveness of laparoscopic common bile duct exploration (CBDE) compared to endoscopic retrograde cholangiopancreatography (ERCP) and cholecystectomy for the emergency management of common bile duct (CBD) stones. Methodology: A retrospective case note review was conducted on consecutive patients undergoing emergency management of CBD stones using either CBDE, or ERCP and cholecystectomy at a single centre between January 2014-October 2014. Data on admission and procedural costs, length of hospital stay, postoperative complications and further stone related interventions were analysed. Results: A total of 350 patients were analysed. Among them, 299 patients underwent CBDE at the time of cholecystectomy, while the remaining 51 underwent ERCP either pre-, intra- or post cholecystectomy. CBDE was associated with lower overall costs compared to ERCP with an average hospital stay cost of $13,093 vs $22,930 respectively. This was largely attributed to shorter hospital stays (6.5 vs 10.3 days), decreased need for intensive care unit admission and fewer postoperative interventions within the CBDE group. Notably, single procedure laparoscopic cholecystectomy with CBDE demonstrated decreased operative costs compared to laparoscopic cholecystectomy combined with ERCP pre-/intra- or post-operatively ($3,747 vs. $4,641). Conclusion: Emergent CBDE is a cost-effective alternative to ERCP for managing CBD stones when combined with cholecystectomy. The upfront investment in equipment for CBDE and increased cholecystectomy procedural time is counterbalanced by reduced hospital stay, fewer procedures and subsequent cost savings. Economic considerations, in conjunction with clinical outcomes, should inform the selection of the optimal approach for CBD stone management in emergency settings.

Keywords: choledocolithiasis, management, cost-effectiveness, endoscopic retrograde cholangiopancreatography, ERCP, CBDE, common bile duct exploration

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Authors: Alper T. Celebi, Ali Beskok

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Electroosmotic (EO) slip flows in nanochannels are investigated using non-equilibrium molecular dynamics (MD) simulations, and the results are compared with analytical solution of Poisson-Boltzmann and Stokes (PB-S) equations with slip contribution. The ultimate objective of this study is to show that well-known continuum flow model can accurately predict the EO velocity profiles in nanochannels using the slip lengths and apparent viscosities obtained from force-driven flow simulations performed at various liquid-wall interaction strengths. EO flow of aqueous NaCl solution in silicon nanochannels are simulated under realistic electrochemical conditions within the validity region of Poisson-Boltzmann theory. A physical surface charge density is determined for nanochannels based on dissociations of silanol functional groups on channel surfaces at known salt concentration, temperature and local pH. First, we present results of density profiles and ion distributions by equilibrium MD simulations, ensuring that the desired thermodynamic state and ionic conditions are satisfied. Next, force-driven nanochannel flow simulations are performed to predict the apparent viscosity of ionic solution between charged surfaces and slip lengths. Parabolic velocity profiles obtained from force-driven flow simulations are fitted to a second-order polynomial equation, where viscosity and slip lengths are quantified by comparing the coefficients of the fitted equation with continuum flow model. Presence of charged surface increases the viscosity of ionic solution while the velocity-slip at wall decreases. Afterwards, EO flow simulations are carried out under uniform electric field for different liquid-wall interaction strengths. Velocity profiles present finite slips near walls, followed with a conventional viscous flow profile in the electrical double layer that reaches a bulk flow region in the center of the channel. The EO flow enhances with increased slip at the walls, which depends on wall-liquid interaction strength and the surface charge. MD velocity profiles are compared with the predictions from analytical solutions of the slip modified PB-S equation, where the slip length and apparent viscosity values are obtained from force-driven flow simulations in charged silicon nano-channels. Our MD results show good agreements with the analytical solutions at various slip conditions, verifying the validity of PB-S equation in nanochannels as small as 3.5 nm. In addition, the continuum model normalizes slip length with the Debye length instead of the channel height, which implies that enhancement in EO flows is independent of the channel height. Further MD simulations performed at different channel heights also shows that the flow enhancement due to slip is independent of the channel height. This is important because slip enhanced EO flow is observable even in micro-channels experiments by using a hydrophobic channel with large slip and high conductivity solutions with small Debye length. The present study provides an advanced understanding of EO flows in nanochannels. Correct characterization of nanoscale EO slip flow is crucial to discover the extent of well-known continuum models, which is required for various applications spanning from ion separation to drug delivery and bio-fluidic analysis.

Keywords: electroosmotic flow, molecular dynamics, slip length, velocity-slip

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Authors: Samaniego Campoverde José Enrique, Rosero Muñoz Jorge Enrique, Luzcando Narea Lorena Elizabeth

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This paper presents a practical and theoretical model for the operation of the Tesla coil using digital signal processing. The research is based on the analysis of ten scientific papers exploring the development and operation of the Tesla coil. Starting from the Testa coil, several modifications were carried out on the Tesla coil, with the aim of amplifying the digital signal by making use of digital signal processing. To achieve this, an amplifier with a transistor and digital filters provided by MATLAB software were used, which were chosen according to the characteristics of the signals in question.

Keywords: tesla coil, digital signal process, equalizer, graphical environment

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Authors: Alberto Hananel

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The aim of this work is to modelize the occlusion of a person with temporomandibular disorders as an evolutionary equation and approach its solution by the construction and characterizing of discrete variational splines. To formulate the problem, certain boundary conditions have been considered. After showing the existence and the uniqueness of the solution of such a problem, a convergence result of a discrete variational evolutionary spline is shown. A stress analysis of the occlusion of a human jaw with temporomandibular disorders by finite elements is carried out in FreeFem++ in order to prove the validity of the presented method.

Keywords: approximation, evolutionary PDE, Finite Element Method, temporomandibular disorders, variational spline

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Authors: Ransford Kwaku Afeadie

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Purpose – The health challenges that characterises most of the migrants’ urban slums raise a lot of concern for their well-being. Health-seeking behaviour becomes an important step towards maintaining a healthy life. The importance of contextual issues is necessary to help meet specific community health needs and programmes. Therefore, this study aims to bridge the knowledge gap by investigating health-seeking behaviour disparity among rural-urban labour migrant slum dwellers before and after migration to the urban slums of Madina in the Greater Accra Region, Ghana. Design/methodology/approach – The author used explanatory sequential approach of research investigation. Questionnaire and interview guides were used to collect data from the respondents; however, in the absence of an existing reliable sampling frame, the various communities were selected by the use of cluster sampling proportional to size. At the second stage, a simple random sampling was used to select the various household heads. A total of 241 questionnaires were retrieved from the respondents representing a response rate of 100%. The author used the purposive sampling technique to conduct eight in-depth interviews and six key informants’ interviews. Findings – The author found various discrepancies in many of the activities that could fulfill substantial health-seeking behaviour in the slum as compared to migrant’s places of origin. The reason for coming to the slum amidst many settlements needs and low education background are the factors that accounted for this. This study, therefore, contradicts the proposition held by the health belief model. It is, therefore, important to note that contextual issues are key, in this case, rural-urban migrant slums present a different dynamic that must be taken into account when designing health programmes for such settings. Originality/value – Many, if not all the, studies on health-seeking behaviour have focused on urban slums without taking into account urban migrants’ slums. Such a failure to take into account the variations of the health needs of migrants’ urban slum settings can eventually lead to a mismatch of health programmes meant to address their challenges. Therefore, this study brings to the fore such variations that must be taken into account when designing health programmes. The study also indicates that even with the same people, there were disparities in terms of health-seeking behaviour in the slum and at places of origin.

Keywords: health-seeking behaviour, rural–urban migration, urban slums, health belief model

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Authors: Francesca Marsili

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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

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Authors: Thomas Adi Purnomo Sidhi

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Nowadays, network is an essential need in almost every part of human daily activities. People now can seamlessly connect to others through the Internet. With advanced technology, our personal data now can be more easily accessed. One of many components we are concerned for delivering the best network is a security issue. This paper is proposing a method that provides more options for security. This research aims to improve network security by focusing on the physical layer which is the first layer of the OSI model. The layer consists of the basic networking hardware transmission technologies of a network. With the use of observation method, the research produces a schematic design for enhancing the network security through the gray code converter.

Keywords: network, network security, grey code, physical layer

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Authors: Teresa B. King

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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

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Authors: Rishana Bilimoria, Selina Tang, Sajni Shah, Marianne Henien, Christopher Sproat

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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

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Authors: Muhammet Kurucu

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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

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Authors: Volkmar Nolting

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Fatigue crack growth prediction has become an important topic in both engineering and non-destructive evaluation. Crack propagation is influenced by the mechanical properties of the material and is conveniently modelled by the Paris-Erdogan equation. The critical crack size and the total number of load cycles are calculated. From a Larson-Miller plot the maximum operational temperature can for a given stress level be determined so that failure does not occur within a given time interval t. The study is used to determine a reasonable inspection cycle and thus enhances operational safety and reduces costs.

Keywords: fracturemechanics, crack growth prediction, lifetime of a component, structural health monitoring

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Authors: Chahrazed Salhi, Ayoub Zeroual, Yasmina Hamitouche

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Soil water erosion poses a significant threat to the watersheds in Algeria today. The degradation of storage capacity in large dams over the past two decades, primarily due to erosion, necessitates a comprehensive understanding of the factors that contribute to soil erosion. The Isser watershed, located in the Northwestern region of Algeria, faces additional challenges such as recurrent droughts and the presence of delicate marl and clay outcrops, which amplify its susceptibility to water erosion. This study aims to employ advanced techniques such as Geographic Information Systems (GIS) and Remote Sensing (RS), in conjunction with the Canonical Correlation Analysis (CCA) method and Soil Water Assessment Tool (SWAT) model, to predict specific erosion patterns and analyze the key factors influencing erosion in the Isser basin. To accomplish this, an array of data sources including rainfall, climatic, hydrometric, land use, soil, digital elevation, and satellite data were utilized. The application of the SWAT model to the Isser basin yielded an average annual soil loss of approximately 16 t/ha/year. Particularly high erosion rates, exceeding 12 T/ha/year, were observed in the central and southern parts of the basin, encompassing 41% of the total basin area. Through Canonical Correlation Analysis, it was determined that vegetation cover and topography exerted the most substantial influence on erosion. Consequently, the study identified significant and spatially heterogeneous erosion throughout the study area. The impact of land topography on soil loss was found to be directly proportional, while vegetation cover exhibited an inverse proportional relationship. Modeling specific erosion for the Ladrat dam sub-basin estimated a rate of around 39 T/ha/year, thus accounting for the recorded capacity loss of 17.80% compared to the bathymetric survey conducted in 2019. The findings of this research provide valuable decision-support tools for soil conservation managers, empowering them to make informed decisions regarding soil conservation measures.

Keywords: Isser watershed, RS, CCA, SWAT, vegetation cover, topography

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Authors: Bhaumik Patel, Amit Gotecha

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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 137

Authors: Suliman Al-Fayoumi, Sherri Amberg, Huafeng Zhou, Jack W. Singer, James P. Dean

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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

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Authors: Yunfeng Shan, Xiaoliang Wang, Youjun Zhou

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Whole-genome data from two lungfish species, along with other species, present a valuable opportunity to re-investigate the longstanding debate regarding the evolutionary relationships among tetrapods, lungfishes, and coelacanths. However, the use of bootstrap support has become outdated for large-scale phylogenomic data. Without robust phylogenetic support, the phylogenetic trees become meaningless. Therefore, it is necessary to re-evaluate the phylogenies of tetrapods, lungfishes, and coelacanths using novel measures of phylogenetic support specifically designed for phylogenomic data, as the previous phylogenies were based on 100% bootstrap support. Our findings consistently provide strong evidence favoring lungfish as the closest living relative of tetrapods. This conclusion is based on high internode certainty, relative gene support, and high gene concordance factor. The evidence stems from five previous datasets derived from lungfish transcriptomes. These results yield fresh insights into the three hypotheses regarding the phylogenies of tetrapods, lungfishes, and coelacanths. Importantly, these hypotheses are not mere conjectures but are substantiated by a significant number of genes. Analyzing real biological data further demonstrates that the inclusion of additional taxa leads to more diverse tree topologies. Consequently, gene trees and species trees may not be identical even when whole-genome sequencing data is utilized. However, it is worth noting that many gene trees can accurately reflect the species tree if an appropriate number of taxa, typically ranging from six to ten, are sampled. Therefore, it is crucial to carefully select the number of taxa and an appropriate outgroup, such as slow-evolving species, while excluding fast-evolving taxa as outgroups to mitigate the adverse effects of long-branch attraction and achieve an accurate reconstruction of the species tree. This is particularly important as more whole-genome sequencing data becomes available.

Keywords: novel measures of phylogenetic support for phylogenomic data, gene concordance factor confidence, relative gene support, internode certainty, origin of tetrapods

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Authors: Liang Qin, Hanan M. D. Habbi

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A robust sensorless speed for permanent magnet synchronous motor (PMSM) has been presented for estimation of stator flux components and rotor speed based on The Extended Kalman Filter (EKF). The model of PMSM and its EKF models are modeled in Matlab /Sirnulink environment. The proposed EKF speed estimation method is also proved insensitive to the PMSM parameter variations. Simulation results demonstrate a good performance and robustness.

Keywords: DTC, Extended Kalman Filter (EKF), PMSM, sensorless control, anti-windup PI

Procedia PDF Downloads 663

Authors: Helge Rupprich, Elke Knisel

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In a time of mediazation and reduced physical movement, it is important to change passivity (akinesa) into physical activity to improve health. The approach is to encourage children, junior athletes, recreational athletes, and semi-professional athletes to do sports while attending a top sport event. The concept has the slogan: get out off your seat and move! A top sport event of a series of professional beach volleyball tournaments with 330.000 life viewers, 13,70 million cumulative reach viewers and 215,13 million advertising contacts is used as framework for different sports didactic approaches, social integrative approaches and migration valuations. An important aim is to use the big radiant power of the top sport event to extract active participants from the viewers of the top sport event. Even if it is the goal to improve physical activity, it is necessary to differentiate between the didactic approaches. The first approach contains psycho motoric exercises with children (N=158) between two and five years which was used in the project ‘largest sandbox of the city’. The second approach is social integration and promotion of activity of students (N=54) in the form of a student beach volleyball tournament. The third approach is activity in companies. It is based on the idea of health motivation of employees (N=62) in a big beach volleyball tournament. Fourth approach is to improve the sports leisure time activities of recreational athletes (N=292) in different beach volleyball tournaments. Fifthly approach is to build a foreign friendly measure which is implemented in junior athlete training with the French and German junior national team (N=16). Sixthly approach is to give semi professional athletes a tournament to develop their relation to active life. Seventh approach is social integration for disadvantaged people (N=123) in form of training with professional athletes. The top sport beach volleyball tournament had 80 athletes (N=80) and 34.000 viewers. In sum 785 athletes (N=785) did sports in 13 days. Over 34.000 viewers where counted in the first three days of top sport event. The project was evaluated positively by the City of Dresden, Politics of Saxony and the participants and will be continued in Dresden and expanded for the season 2015 in Jena.

Keywords: beach volleyball, event, sports didactic, sports project

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Authors: Shyam Sunder Gupta

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The current theory for the creation of the universe, the Big Bang theory, is widely accepted but leaves some unanswered questions. It does not explain the origin of the singularity or what causes the Big Bang. The theory of the Big Bang also does not explain why there is such a huge amount of dark energy and dark matter in our universe. Also, there is a question related to one universe or multiple universes which needs to be answered. This research addresses these questions using the Bhagvat Puran and other Vedic scriptures as the basis. There is a Unique Pure Energy Field that is eternal, infinite, and finest of all and never transforms when in its original form. The Carrier Particles of Unique Pure Energy are Param-anus- Fundamental Energy Particles. Param-anus and a combination of these particles create bigger particles from which the Universe gets created. For creation to initiate, Unique Pure Energy is represented in three phases: positive phase energy, neutral phase eternal time energy and negative phase energy. Positive phase energy further expands in three forms of creative energies (CE1, CE2andCE3). From CE1 energy, three energy modes, mode of activation, mode of action, and mode of darkness, were created. From these three modes, 16 Principles, subtlest forms of energies, namely Pradhan, Mahat-tattva, Time, Ego, Intellect, Mind, Sound, Space, Touch, Air, Form, Fire, Taste, Water, Smell, and Earth, get created. In the Mahat-tattva, dominant in the Mode of Darkness, CE1 energy creates innumerable primary singularities from seven principles: Pradhan, Mahat-tattva, Ego, Sky, Air, Fire, and Water. CE1 energy gets divided as CE2 and enters, along with three modes and time, in each singularity, and primary Big Bang takes place, and innumerable Invisible Universes get created. Each Universe has seven coverings of 7 principles, and each layer is 10 times thicker than the previous layer. By energy CE2, space in Invisible Universe under the coverings is divided into two halves. In the lower half, the process of evolution gets initiated, and seeds of 24 elements get created, out of which 5 fundamental elements, building blocks of matter, Sky, Air, Fire, Water and Earth, create seeds of stars, planets, galaxies and all other matter. Since 5 fundamental elements get created out of the mode of darkness, it explains why there is so much dark energy and dark matter in our Universe. This process of creation, in the lower half of Invisible universe continues for 2.16 billion years. Further, in the lower part of the energy field, exactly at the Centre of Invisible Universe, Secondary Singularity is created, through which, by force of Mode of Action, Secondary Big Bang takes place and Visible Universe gets created in the shape of Lotus Flower, expanding into upper part. Visible matter starts appearing after a gap of 360,000 years. Within the Visible Universe, a small part gets created known as the Phenomenal Material World, which is our Solar System, the sun being in the Centre. Diameter of Solar planetary system is 6.4 billion km.

Keywords: invisible universe, phenomenal material world, primary Big Bang, secondary Big Bang, singularities, visible universe

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Authors: Zbigniew Czyż, Adam Majczak, Lukasz Grabowski

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The paper presents a description of geometric models, computational algorithms, and results of numerical analyses of charge exchange in a two-stroke opposed-piston engine. The research engine was a newly designed internal Diesel engine. The unit is characterized by three cylinders in which three pairs of opposed-pistons operate. The engine will generate a power output equal to 100 kW at a crankshaft rotation speed of 3800-4000 rpm. The numerical investigations were carried out using ANSYS FLUENT solver. Numerical research, in contrast to experimental research, allows us to validate project assumptions and avoid costly prototype preparation for experimental tests. This makes it possible to optimize the geometrical model in countless variants with no production costs. The geometrical model includes an intake manifold, a cylinder, and an outlet manifold. The study was conducted for a series of modifications of manifolds and intake and exhaust ports to optimize the charge exchange process in the engine. The calculations specified a swirl coefficient obtained under stationary conditions for a full opening of intake and exhaust ports as well as a CA value of 280° for all cylinders. In addition, mass flow rates were identified separately in all of the intake and exhaust ports to achieve the best possible uniformity of flow in the individual cylinders. For the models under consideration, velocity, pressure and streamline contours were generated in important cross sections. The developed models are designed primarily to minimize the flow drag through the intake and exhaust ports while the mass flow rate increases. Firstly, in order to calculate the swirl ratio [-], tangential velocity v [m/s] and then angular velocity ω [rad / s] with respect to the charge as the mean of each element were calculated. The paper contains comparative analyses of all the intake and exhaust manifolds of the designed engine. Acknowledgement: This work has been realized in the cooperation with The Construction Office of WSK "PZL-KALISZ" S.A." and is part of Grant Agreement No. POIR.01.02.00-00-0002/15 financed by the Polish National Centre for Research and Development.

Keywords: computational fluid dynamics, engine swirl, fluid mechanics, mass flow rates, numerical analysis, opposed-piston engine

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Authors: Azmat Hussain

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Great Taj Mahal is built on well foundation. Well foundation can be constructed on the dry bed or after making sand Island. Cassions are relatively easy to construct provide sinking operations are smooth without much hindrance. Well foundation have many constructional difficulties, viz prolonged sinking period, tilting etc. These problems become worse and take more time when working season is winter. Especially in Indian Areas like Jammu & Kashmir (Srinagar) where technology lacks. The only thing Engineers can do is to wait till working conditions become suitable. A case study is presented in the paper exploring the feasibility of pile foundation.

Keywords: well foundation, pile foundation, equipments used, pile construction

Procedia PDF Downloads 268

Authors: Nguyen-Thanh Son

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Flood is among the most frequent and costliest natural hazards. The flood disasters especially affect the poor people in rural areas, who are heavily dependent on agriculture and have lower incomes. Cambodia is identified as one of the most climate-vulnerable countries in the world, ranked 13th out of 181 countries most affected by the impacts of climate change. Flood monitoring is thus a strategic priority at national and regional levels because policymakers need reliable spatial and temporal information on flood-prone areas to form successful monitoring programs to reduce possible impacts on the country’s economy and people’s likelihood. This study aims to develop methods for flood mapping and assessment from MODIS data in Cambodia. We processed the data for the period from 2000 to 2017, following three main steps: (1) data pre-processing to construct smooth time-series vegetation and water surface indices, (2) delineation of flood-prone areas, and (3) accuracy assessment. The results of flood mapping were verified with the ground reference data, indicating the overall accuracy of 88.7% and a Kappa coefficient of 0.77, respectively. These results were reaffirmed by close agreement between the flood-mapping area and ground reference data, with the correlation coefficient of determination (R²) of 0.94. The seasonally flooded areas observed for 2010, 2015, and 2016 were remarkably smaller than other years, mainly attributed to the El Niño weather phenomenon exacerbated by impacts of climate change. Eventually, although several sources potentially lowered the mapping accuracy of flood-prone areas, including image cloud contamination, mixed-pixel issues, and low-resolution bias between the mapping results and ground reference data, our methods indicated the satisfactory results for delineating spatiotemporal evolutions of floods. The results in the form of quantitative information on spatiotemporal flood distributions could be beneficial to policymakers in evaluating their management strategies for mitigating the negative effects of floods on agriculture and people’s likelihood in the country.

Keywords: MODIS, flood, mapping, Cambodia

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Authors: Poojan Gharat, Haridas Pal, Sharmistha Dutta Choudhury

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Tuning photophysical properties of guest dyes through host-guest interactions involving macrocyclic hosts are the attractive research areas since past few decades, as these changes can directly be implemented in chemical sensing, molecular recognition, fluorescence imaging and dye laser applications. Excited state intramolecular proton transfer (ESIPT) is an intramolecular prototautomerization process display by some specific dyes. The process is quite amenable to tunability by the presence of different macrocyclic hosts. The present study explores the interesting effect of p-sulfonatocalix[n]arene (SCXn) and cyclodextrin (CD) hosts on the excited-state prototautomeric equilibrium of Chrysazine (CZ), a model antitumour drug. CZ exists exclusively in its normal form (N) in the ground state. However, in the excited state, the excited N* form undergoes ESIPT along with its pre-existing intramolecular hydrogen bonds, giving the excited state prototautomer (T*). Accordingly, CZ shows a single absorption band due to N form, but two emission bands due to N* and T* forms. Facile prototautomerization of CZ is considerably inhibited when the dye gets bound to SCXn hosts. However, in spite of lower binding affinity, the inhibition is more profound with SCX6 host as compared to SCX4 host. For CD-CZ system, while prototautomerization process is hindered by the presence of β-CD, it remains unaffected in the presence of γCD. Reduction in the prototautomerization process of CZ by SCXn and βCD hosts is unusual, because T* form is less dipolar in nature than the N*, hence binding of CZ within relatively hydrophobic hosts cavities should have enhanced the prototautomerization process. At the same time, considering the similar chemical nature of two CD hosts, their effect on prototautomerization process of CZ would have also been similar. The atypical effects on the prototautomerization process of CZ by the studied hosts are suggested to arise due to the partial inclusion or external binding of CZ with the hosts. As a result, there is a strong possibility of intermolecular H-bonding interaction between CZ dye and the functional groups present at the portals of SCXn and βCD hosts. Formation of these intermolecular H-bonds effectively causes the pre-existing intramolecular H-bonding network within CZ molecule to become weak, and this consequently reduces the prototautomerization process for the dye. Our results suggest that rather than the binding affinity between the dye and host, it is the orientation of CZ in the case of SCXn-CZ complexes and the binding stoichiometry in the case of CD-CZ complexes that play the predominant role in influencing the prototautomeric equilibrium of the dye CZ. In the case of SCXn-CZ complexes, the results obtained through experimental findings are well supported by quantum chemical calculations. Similarly for CD-CZ systems, binding stoichiometries obtained through geometry optimization studies on the complexes between CZ and CD hosts correlate nicely with the experimental results. Formation of βCD-CZ complexes with 1:1 stoichiometry while formation of γCD-CZ complexes with 1:1, 1:2 and 2:2 stoichiometries are revealed from geometry optimization studies and these results are in good accordance with the observed effects by the βCD and γCD hosts on the ESIPT process of CZ dye.

Keywords: intermolecular proton transfer, macrocyclic hosts, quantum chemical studies, photophysical studies

Procedia PDF Downloads 119