Search results for: customer information system
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 25500

Search results for: customer information system

2700 Impact of Elements of Rock and Water Combination on Landscape Perception: A Visual Landscape Quality Assessment on Kaludiya Pokuna in Sri Lanka

Authors: Clarence Dissanayake, Anishka A. Hettiarachchi

Abstract:

Landscape architecture needs to encompass a placemaking process carefully composing and manipulating landscape elements to address perceptual needs of humans, especially aesthetic, psychological and spiritual. The objective of this qualitative investigation is to inquire the impact of elements of rock and water combination on landscape perception and related feelings, emotions, and behavior. The past empirical studies have assessed the impact of landscape elements in isolation on user preference, yet the combined effect of elements have been less considered. This research was conducted with reference to the verity of qualities of water and rock through a visual landscape quality assessment focusing on landscape qualities derived from five visual concepts (coherence, historicity imageability, naturalness, and ephemera). 'Kaludiya Pokuna' archeological site in Anuradhapura was investigated with a sample of University students (n=19, male 14, female 5, age 20-25) using a five-point Likert scale via a perception based questionnaire and a visitor employed photographic survey (VEP). Two hypothetical questions were taken into investigation concerning biophilic (naturalness) and topophilic (historicity) aspects of humans to prefer a landscape with rock and water. The findings revealed that this combination encourages both biophilic and topophilic aspects, but in varying degrees. The identified hierarchy of visual concepts based on visitor’s preference signify coherence (93%), historicity (89%), imageability (79%), naturalness (75%) and ephemera (70%) respectively. It was further revealed that this combination creates a scenery more coherent dominating information processing aspect of humans to perceive a landscape over the biophilic and topophilic aspects. Different characteristics and secondary landscape effects generated by rock and water combination were found to affect in transforming a space into a place, full filling the aesthetic and spiritual aspects of the visitors. These findings enhance a means of making places for people, resource management and historical landscape conservation. Equalization of gender based participation, taking diverse cases and increasing the sample size with more analytical photographic analysis are recommended to enhance the quality of further research.

Keywords: landscape perception, visitor’s preference, rock and water combination, visual concepts

Procedia PDF Downloads 206
2699 Cooperation of Unmanned Vehicles for Accomplishing Missions

Authors: Ahmet Ozcan, Onder Alparslan, Anil Sezgin, Omer Cetin

Abstract:

The use of unmanned systems for different purposes has become very popular over the past decade. Expectations from these systems have also shown an incredible increase in this parallel. But meeting the demands of the tasks are often not possible with the usage of a single unmanned vehicle in a mission, so it is necessary to use multiple autonomous vehicles with different abilities together in coordination. Therefore the usage of the same type of vehicles together as a swarm is helped especially to satisfy the time constraints of the missions effectively. In other words, it allows sharing the workload by the various numbers of homogenous platforms together. Besides, it is possible to say there are many kinds of problems that require the usage of the different capabilities of the heterogeneous platforms together cooperatively to achieve successful results. In this case, cooperative working brings additional problems beyond the homogeneous clusters. In the scenario presented as an example problem, it is expected that an autonomous ground vehicle, which is lack of its position information, manage to perform point-to-point navigation without losing its way in a previously unknown labyrinth. Furthermore, the ground vehicle is equipped with very limited sensors such as ultrasonic sensors that can detect obstacles. It is very hard to plan or complete the mission for the ground vehicle by self without lost its way in the unknown labyrinth. Thus, in order to assist the ground vehicle, the autonomous air drone is also used to solve the problem cooperatively. The autonomous drone also has limited sensors like downward looking camera and IMU, and it also lacks computing its global position. In this context, it is aimed to solve the problem effectively without taking additional support or input from the outside, just benefiting capabilities of two autonomous vehicles. To manage the point-to-point navigation in a previously unknown labyrinth, the platforms have to work together coordinated. In this paper, cooperative work of heterogeneous unmanned systems is handled in an applied sample scenario, and it is mentioned that how to work together with an autonomous ground vehicle and the autonomous flying platform together in a harmony to take advantage of different platform-specific capabilities. The difficulties of using heterogeneous multiple autonomous platforms in a mission are put forward, and the successful solutions are defined and implemented against the problems like spatially distributed tasks planning, simultaneous coordinated motion, effective communication, and sensor fusion.

Keywords: unmanned systems, heterogeneous autonomous vehicles, coordination, task planning

Procedia PDF Downloads 113
2698 A Dual-Mode Infinite Horizon Predictive Control Algorithm for Load Tracking in PUSPATI TRIGA Reactor

Authors: Mohd Sabri Minhat, Nurul Adilla Mohd Subha

Abstract:

The PUSPATI TRIGA Reactor (RTP), Malaysia reached its first criticality on June 28, 1982, with power capacity 1MW thermal. The Feedback Control Algorithm (FCA) which is conventional Proportional-Integral (PI) controller, was used for present power control method to control fission process in RTP. It is important to ensure the core power always stable and follows load tracking within acceptable steady-state error and minimum settling time to reach steady-state power. At this time, the system could be considered not well-posed with power tracking performance. However, there is still potential to improve current performance by developing next generation of a novel design nuclear core power control. In this paper, the dual-mode predictions which are proposed in modelling Optimal Model Predictive Control (OMPC), is presented in a state-space model to control the core power. The model for core power control was based on mathematical models of the reactor core, OMPC, and control rods selection algorithm. The mathematical models of the reactor core were based on neutronic models, thermal hydraulic models, and reactivity models. The dual-mode prediction in OMPC for transient and terminal modes was based on the implementation of a Linear Quadratic Regulator (LQR) in designing the core power control. The combination of dual-mode prediction and Lyapunov which deal with summations in cost function over an infinite horizon is intended to eliminate some of the fundamental weaknesses related to MPC. This paper shows the behaviour of OMPC to deal with tracking, regulation problem, disturbance rejection and caters for parameter uncertainty. The comparison of both tracking and regulating performance is analysed between the conventional controller and OMPC by numerical simulations. In conclusion, the proposed OMPC has shown significant performance in load tracking and regulating core power for nuclear reactor with guarantee stabilising in the closed-loop.

Keywords: core power control, dual-mode prediction, load tracking, optimal model predictive control

Procedia PDF Downloads 148
2697 Digital Structural Monitoring Tools @ADaPT for Cracks Initiation and Growth due to Mechanical Damage Mechanism

Authors: Faizul Azly Abd Dzubir, Muhammad F. Othman

Abstract:

Conventional structural health monitoring approach for mechanical equipment uses inspection data from Non-Destructive Testing (NDT) during plant shut down window and fitness for service evaluation to estimate the integrity of the equipment that is prone to crack damage. Yet, this forecast is fraught with uncertainty because it is often based on assumptions of future operational parameters, and the prediction is not continuous or online. Advanced Diagnostic and Prognostic Technology (ADaPT) uses Acoustic Emission (AE) technology and a stochastic prognostic model to provide real-time monitoring and prediction of mechanical defects or cracks. The forecast can help the plant authority handle their cracked equipment before it ruptures, causing an unscheduled shutdown of the facility. The ADaPT employs process historical data trending, finite element analysis, fitness for service, and probabilistic statistical analysis to develop a prediction model for crack initiation and growth due to mechanical damage. The prediction model is combined with live equipment operating data for real-time prediction of the remaining life span owing to fracture. ADaPT was devised at a hot combined feed exchanger (HCFE) that had suffered creep crack damage. The ADaPT tool predicts the initiation of a crack at the top weldment area by April 2019. During the shutdown window in April 2019, a crack was discovered and repaired. Furthermore, ADaPT successfully advised the plant owner to run at full capacity and improve output by up to 7% by April 2019. ADaPT was also used on a coke drum that had extensive fatigue cracking. The initial cracks are declared safe with ADaPT, with remaining crack lifetimes extended another five (5) months, just in time for another planned facility downtime to execute repair. The prediction model, when combined with plant information data, allows plant operators to continuously monitor crack propagation caused by mechanical damage for improved maintenance planning and to avoid costly shutdowns to repair immediately.

Keywords: mechanical damage, cracks, continuous monitoring tool, remaining life, acoustic emission, prognostic model

Procedia PDF Downloads 63
2696 Detection of Abnormal Process Behavior in Copper Solvent Extraction by Principal Component Analysis

Authors: Kirill Filianin, Satu-Pia Reinikainen, Tuomo Sainio

Abstract:

Frequent measurements of product steam quality create a data overload that becomes more and more difficult to handle. In the current study, plant history data with multiple variables was successfully treated by principal component analysis to detect abnormal process behavior, particularly, in copper solvent extraction. The multivariate model is based on the concentration levels of main process metals recorded by the industrial on-stream x-ray fluorescence analyzer. After mean-centering and normalization of concentration data set, two-dimensional multivariate model under principal component analysis algorithm was constructed. Normal operating conditions were defined through control limits that were assigned to squared score values on x-axis and to residual values on y-axis. 80 percent of the data set were taken as the training set and the multivariate model was tested with the remaining 20 percent of data. Model testing showed successful application of control limits to detect abnormal behavior of copper solvent extraction process as early warnings. Compared to the conventional techniques of analyzing one variable at a time, the proposed model allows to detect on-line a process failure using information from all process variables simultaneously. Complex industrial equipment combined with advanced mathematical tools may be used for on-line monitoring both of process streams’ composition and final product quality. Defining normal operating conditions of the process supports reliable decision making in a process control room. Thus, industrial x-ray fluorescence analyzers equipped with integrated data processing toolbox allows more flexibility in copper plant operation. The additional multivariate process control and monitoring procedures are recommended to apply separately for the major components and for the impurities. Principal component analysis may be utilized not only in control of major elements’ content in process streams, but also for continuous monitoring of plant feed. The proposed approach has a potential in on-line instrumentation providing fast, robust and cheap application with automation abilities.

Keywords: abnormal process behavior, failure detection, principal component analysis, solvent extraction

Procedia PDF Downloads 295
2695 Evaluation of Different Food Baits by Using Kill Traps for the Control of Lesser Bandicoot Rat (Bandicota bengalensis) in Field Crops of Pothwar Plateau, Pakistan

Authors: Nadeem Munawar, Iftikhar Hussain, Tariq Mahmood

Abstract:

The lesser bandicoot rat (Bandicota bengalensis) is widely distributed and a serious agricultural pest in Pakistan. It has wide adaptation with rice-wheat-sugarcane cropping systems of Punjab, Sindh and Khyber Pakhtunkhwa and wheat-groundnut cropping system of Pothwar area, thus inflicting heavy losses to these crops. Comparative efficacies of four food baits (onion, guava, potato and peanut butter smeared bread/Chapatti) were tested in multiple feeding tests for kill trapping of this rat species in the Pothwar Plateau between October 2013 to July 2014 at the sowing, tilling, flowering and maturity stages of wheat, groundnut and millet crops. The results revealed that guava was the most preferred bait as compared to the rest of three, presumably due to particular taste and smell of the guava. The relative efficacies of all four tested baits guava also scoring the highest trapping success of 16.94 ± 1.42 percent, followed by peanut butter, potato, and onion with trapping successes of 10.52 ± 1.30, 7.82 ± 1.21 and 4.5 ± 1.10 percent, respectively. In various crop stages and season-wise the highest trapping success was achieved at maturity stages of the crops, presumably due to higher surface activity of the rat because of favorable climatic conditions, good shelter, and food abundance. Moreover, the maturity stage of wheat crop coincided with spring breeding season and maturity stages of millet and groundnut match with monsoon/autumn breeding peak of the lesser bandicoot rat in Pothwar area. The preferred order among four baits tested was guava > peanut butter > potato > onion. The study recommends that the farmers should periodically carry out rodent trapping at the beginning of each crop season and during non-breeding seasons of this rodent pest when the populations are low in numbers and restricted under crop boundary vegetation, particularly during very hot and cold months.

Keywords: Bandicota bengalensis, efficacy, food baits, Pothwar

Procedia PDF Downloads 256
2694 Tunnel Convergence Monitoring by Distributed Fiber Optics Embedded into Concrete

Authors: R. Farhoud, G. Hermand, S. Delepine-lesoille

Abstract:

Future underground facility of French radioactive waste disposal, named Cigeo, is designed to store intermediate and high level - long-lived French radioactive waste. Intermediate level waste cells are tunnel-like, about 400m length and 65 m² section, equipped with several concrete layers, which can be grouted in situ or composed of tunnel elements pre-grouted. The operating space into cells, to allow putting or removing waste containers, should be monitored for several decades without any maintenance. To provide the required information, design was performed and tested in situ in Andra’s underground laboratory (URL) at 500m under the surface. Based on distributed optic fiber sensors (OFS) and backscattered Brillouin for strain and Raman for temperature interrogation technics, the design consists of 2 loops of OFS, at 2 different radiuses, around the monitored section (Orthoradiale strains) and longitudinally. Strains measured by distributed OFS cables were compared to classical vibrating wire extensometers (VWE) and platinum probes (Pt). The OFS cables were composed of 2 cables sensitive to strains and temperatures and one only for temperatures. All cables were connected, between sensitive part and instruments, to hybrid cables to reduce cost. The connection has been made according to 2 technics: splicing fibers in situ after installation or preparing each fiber with a connector and only plugging them together in situ. Another challenge was installing OFS cables along a tunnel mad in several parts, without interruption along several parts. First success consists of the survival rate of sensors after installation and quality of measurements. Indeed, 100% of OFS cables, intended for long-term monitoring, survived installation. Few new configurations were tested with relative success. Measurements obtained were very promising. Indeed, after 3 years of data, no difference was observed between cables and connection methods of OFS and strains fit well with VWE and Pt placed at the same location. Data, from Brillouin instrument sensitive to strains and temperatures, were compensated with data provided by Raman instrument only sensitive to temperature and into a separated fiber. These results provide confidence in the next steps of the qualification processes which consists of testing several data treatment approach for direct analyses.

Keywords: monitoring, fiber optic, sensor, data treatment

Procedia PDF Downloads 116
2693 Women Executives: A Panacea to Incessant Sexual Assaults in Higher Institutions, Federal Polytechnic Nekede Imo State Nigeria as a Case Study

Authors: Ujunma Nnenna Egbuawa

Abstract:

Rape or sexual assault is a hideous crime of violence done predominantly to women and occasionally to men. In institutions of higher learning, it’s mostly experienced within or outside the campus environment due to students who are from different backgrounds socially. These students also have been imbibed with conflicting ethical standards, thus act both morally and amoral with respect to their sexual urges. The most affected among these are the female students who live outside the campus environment that is suitable for any immoral activity. These female students that are victims of rape hardly would want to be identified and this has left them as habitual prey to the unsuspecting predators. The socio-cultural setting has also been a contributory factor to the psychological and physical damage these victims face throughout their time of study as female rape victims. This is an empirical study designed to elicit information from students of Federal Polytechnic Nekede Owerri Imo State Nigeria on whether they have been sexually assaulted or raped and how they handled it thereafter. This institution was used as a case study because the provost of this tertiary institution is a woman whose name is Dr( Mrs ) C.U Njoku who has made consented efforts to ensure these rape victims rise above the social stigma associated with it. This rector has also put in some measures to bring about a decline in cases of rape within and outside the campus environment. She also granted the researcher an oral interview on how she has been able to achieve these and the challenges she hitherto faced in the process. Three research questions and a hypothesis guided the study. Samples of 119 students were used and stratification was done for sex, age and the academic level of the students. 14 item questionnaires were used and data generated from the survey were analyzed using percentages. This workshop would engage the participants by investigating some courses that may help in declining the rate of rape cases within a campus. Also, necessary measures that would be taken to help in sensitizing the tertiary institutions in areas that can aid the healing procedures of these victims. The need also for guidance and counseling unit is also a necessity for the psychological survival of these rape victims. As a result, the participants would gain an increased awareness of the influence of rape and sexual assault on campus. There ought to be a paradigm shift in institutions of higher learning in policies, administrative decisions and introduction of courses that will uplift ethical standards in order to bring about a change both locally and globally.

Keywords: institutions, psychological, sexual assault, socio-cultural

Procedia PDF Downloads 146
2692 Incidence of Lymphoma and Gonorrhea Infection: A Retrospective Study

Authors: Diya Kohli, Amalia Ardeljan, Lexi Frankel, Jose Garcia, Lokesh Manjani, Omar Rashid

Abstract:

Gonorrhea is the second most common sexually transmitted disease (STDs) in the United States of America. Gonorrhea affects the urethra, rectum, or throat and the cervix in females. Lymphoma is a cancer of the immune network called the lymphatic system that includes the lymph nodes/glands, spleen, thymus gland, and bone marrow. Lymphoma can affect many organs in the body. When a lymphocyte develops a genetic mutation, it signals other cells into rapid proliferation that causes many mutated lymphocytes. Multiple studies have explored the incidence of cancer in people infected with STDs such as Gonorrhea. For instance, the studies conducted by Wang Y-C and Co., as well as Caini, S and Co. established a direct co-relationship between Gonorrhea infection and incidence of prostate cancer. We hypothesize that Gonorrhea infection also increases the incidence of Lymphoma in patients. This research study aimed to evaluate the correlation between Gonorrhea infection and the incidence of Lymphoma. The data for the research was provided by a Health Insurance Portability and Accountability Act (HIPAA) compliant national database. This database was utilized to evaluate patients infected with Gonorrhea versus the ones who were not infected to establish a correlation with the prevalence of Lymphoma using ICD-10 and ICD-9 codes. Access to the database was granted by the Holy Cross Health, Fort Lauderdale for academic research. Standard statistical methods were applied throughout. Between January 2010 and December 2019, the query was analyzed and resulted in 254 and 808 patients in both the infected and control group, respectively. The two groups were matched by Age Range and CCI score. The incidence of Lymphoma was 0.998% (254 patients out of 25455) in the Gonorrhea group (patients infected with Gonorrhea that was Lymphoma Positive) compared to 3.174% and 808 patients in the control group (Patients negative for Gonorrhea but with Lymphoma). This was statistically significant by a p-value < 2.210-16 with an OR= 0.431 (95% CI 0.381-0.487). The patients were then matched by antibiotic treatment to avoid treatment bias. The incidence of Lymphoma was 1.215% (82 patients out of 6,748) in the Gonorrhea group compared to 2.949% (199 patients out of 6748) in the control group. This was statistically significant by a p-value <5.410-10 with an OR= 0.468 (95% CI 0.367-0.596). The study shows a statistically significant correlation between Gonorrhea and a reduced incidence of Lymphoma. Further evaluation is recommended to assess the potential of Gonorrhea in reducing Lymphoma.

Keywords: gonorrhea, lymphoma, STDs, cancer, ICD

Procedia PDF Downloads 181
2691 Morphological Investigation of Sprawling Along Emerging Peri-Urban Transit Corridor of Mowe-Ibafo Axis of the Lagos Megacity Region

Authors: Folayele Oluyemi Akindeju, Tobi Joseph Ajoro

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The city as a complex system exhibiting chaotic behaviour is in a state of constant change, in response to prevailing social, economic, environmental and technological factors. Without adequate investigation and control mechanisms to tame the sporadic nature of growth in most urban areas of cities in developing regions, organic sprawling visibly manifests with its attendant problems, most especially at peri-urban areas. The Lagos Megacity region in southwest Nigeria, as one of the largest megacities in the world contends with the challenges of sprawling at the peri-urban areas especially along emerging transit corridors. Due to the seemingly unpredictable nature of this growth, this paper attempts a morphological investigation into the growth of peri-urban settlements along the Mowe-Ibafo transit corridor of the Megacity region over a temporal space of three decades (1984-2014). This study adopts the application of the Fractal Analysis and Regression Analysis methods through the correlation of population density and fractal dimension values to establish the pattern and nature of growth, due to the inadequacies of conventional methods of urban analysis which cannot deal with the unpredictability of such complex urban forms as the peri-urban areas. It was deduced that the dynamic urban expansion in the last three decades resulted in about 74.2% urban change rate between 1984 and 2000 and 63.4% urban change rate between 2000 and 2014. With the R2 value between the fractal dimension and population density been 1, the regression model indicates a positive correlation between Fractal Dimension (D) and Population Density (pop/km2), where the increase in the population density from 5740 pop/km2 to 8060 pop/km2 and later decrease to 7580 pop/km2 leads to an increase in the fractal dimension of urban growth from 1.451 in 1984 to 1.853 in 2014. This, therefore, justifies the ability to predict and determine the nature and direction of growth of complex entities and is sufficient to substantially suggest the need for adequate policy framework towards sustainable urban planning and infrastructural provision in the Peri-urban areas.

Keywords: fractal analysis, Lagos Megacity, peri-urban, sprawling, urban morphology

Procedia PDF Downloads 162
2690 Analysis of Advancements in Process Modeling and Reengineering at Fars Regional Electric Company, Iran

Authors: Mohammad Arabi

Abstract:

Business Process Reengineering (BPR) is a systematic approach to fundamentally redesign organizational processes to achieve significant improvements in organizational performance. At Fars Regional Electric Company, implementing BPR is deemed essential to increase productivity, reduce costs, and improve service quality. This article examines how BPR can help enhance the performance of Fars Regional Electric Company. The objective of this research is to evaluate and analyze the advancements in process modeling and reengineering at Fars Regional Electric Company and to provide solutions for improving the productivity and efficiency of organizational processes. This study aims to demonstrate how BPR can be used to improve organizational processes and enhance the overall performance of the company. This research employs both qualitative and quantitative research methods and includes interviews with senior managers and experts at Fars Regional Electric Company. The analytical tools include process modeling software such as Bizagi and ARIS, and statistical analysis software such as SPSS and Minitab. Data analysis was conducted using advanced statistical methods. The results indicate that the use of BPR techniques can lead to a significant reduction in process execution time and overall improvement in quality. Implementing BPR at Fars Regional Electric Company has led to increased productivity, reduced costs, and improved overall performance of the company. This study shows that with proper implementation of BPR and the use of modeling tools, the company can achieve significant improvements in its processes. Recommendations: (1) Continuous Training for Staff: Invest in continuous training of staff to enhance their skills and knowledge in BPR. (2) Use of Advanced Technologies: Utilize modeling and analysis software to improve processes. (3) Implementation of Effective Management Systems: Employ knowledge and information management systems to enhance organizational performance. (4) Continuous Monitoring and Review of Processes: Regularly review and revise processes to ensure ongoing improvements. This article highlights the importance of improving organizational processes at Fars Regional Electric Company and recommends that managers and decision-makers at the company seriously consider reengineering processes and utilizing modeling technologies to achieve developmental goals and continuous improvement.

Keywords: business process reengineering, electric company, Fars province, process modeling advancements

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2689 Activated Carbon Content Influence in Mineral Barrier Performance

Authors: Raul Guerrero, Sandro Machado, Miriam Carvalho

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Soil and aquifer pollution, caused by hydrocarbon liquid spilling, is induced by misguided operational practices and inefficient safety guidelines. According to the Environmental Brazilian Institute (IBAMA), during 2013 alone, over 472.13 m3 of diesel oil leaked into the environment nationwide for those reported cases only. Regarding the aforementioned information, there’s an indisputable need to adopt appropriate environmental safeguards specially in those areas intended for the production, treatment, transportation and storage of hydrocarbon fluids. According to Brazilian norm, ABNT-NBR 7505-1:2000, compacted soil or mineral barriers used in structural contingency levees, such as storage tanks, are required to present a maximum water permeability coefficient, k, of 1x10-6 cm/s. However, as discussed by several authors, water can not be adopted as the reference fluid to determine the site’s containment performance against organic fluids. Mainly, due to the great discrepancy observed in polarity values (dielectric constant) between water and most organic fluids. Previous studies, within this same research group, proposed an optimal range of values for the soil’s index properties for mineral barrier composition focused on organic fluid containment. Unfortunately, in some circumstances, it is not possible to encounter a type of soil with the required geotechnical characteristics near the containment site, increasing prevention and construction costs, as well as environmental risks. For these specific cases, the use of an organic product or material as an additive to enhance mineral-barrier containment performance may be an attractive geotechnical solution. This paper evaluates the effect of activated carbon (AC) content additions into a clayey soil towards hydrocarbon fluid permeability. Variables such as compaction energy, carbon texture and addition content (0%, 10% and 20%) were analyzed through laboratory falling-head permeability tests using distilled water and commercial diesel as percolating fluids. The obtained results showed that the AC with smaller particle-size reduced k values significantly against diesel, indicating a direct relationship between particle-size reduction (surface area increase) of the organic product and organic fluid containment.

Keywords: activated carbon, clayey soils, permeability, surface area

Procedia PDF Downloads 245
2688 Dynamic Analysis and Clutch Adaptive Prefill in Dual Clutch Transmission

Authors: Bin Zhou, Tongli Lu, Jianwu Zhang, Hongtao Hao

Abstract:

Dual clutch transmissions (DCT) offer a high comfort performance in terms of the gearshift. Hydraulic multi-disk clutches are the key components of DCT, its engagement determines the shifting comfort. The prefill of the clutches requests an initial engagement which the clutches just contact against each other but not transmit substantial torque from the engine, this initial clutch engagement point is called the touch point. Open-loop control is typically implemented for the clutch prefill, a lot of uncertainties, such as oil temperature and clutch wear, significantly affects the prefill, probably resulting in an inappropriate touch point. Underfill causes the engine flaring in gearshift while overfill arises clutch tying up, both deteriorating the shifting comfort of DCT. Therefore, it is important to enable an adaptive capacity for the clutch prefills regarding the uncertainties. In this paper, a dynamic model of the hydraulic actuator system is presented, including the variable force solenoid and clutch piston, and validated by a test. Subsequently, the open-loop clutch prefill is simulated based on the proposed model. Two control parameters of the prefill, fast fill time and stable fill pressure is analyzed with regard to the impact on the prefill. The former has great effects on the pressure transients, the latter directly influences the touch point. Finally, an adaptive method is proposed for the clutch prefill during gear shifting, in which clutch fill control parameters are adjusted adaptively and continually. The adaptive strategy is changing the stable fill pressure according to the current clutch slip during a gearshift, improving the next prefill process. The stable fill pressure is increased by means of the clutch slip while underfill and decreased with a constant value for overfill. The entire strategy is designed in the Simulink/Stateflow, and implemented in the transmission control unit with optimization. Road vehicle test results have shown the strategy realized its adaptive capability and proven it improves the shifting comfort.

Keywords: clutch prefill, clutch slip, dual clutch transmission, touch point, variable force solenoid

Procedia PDF Downloads 300
2687 Vineyard Soils of Karnataka - Characterization, Classification and Soil Site Suitability Evaluation

Authors: Harsha B. R., K. S. Anil Kumar

Abstract:

Land characterization, classification, and soil suitability evaluation of grapes-growing pedons were assessed at fifteen taluks covering four agro climatic zones of Karnataka. Study on problems and potentials of grapes cultivation in selected agro-climatic zones was carried out along with the plant sample analysis. Twenty soil profiles were excavated as study site based on the dominance of area falling under grapes production and existing spatial variability of soils. The detailed information of profiles and horizon wise soil samples were collected to study the morphological, physical, chemical, and fertility characteristics. Climatic analysis and water retention characteristics of soils of major grapes-growing areas were also done. Based on the characterisation and classification study, it was revealed that soils of Doddaballapur (Bangalore Blue and Wine grapes), Bangalore North (GKVK Farm, Rajankunte, and IIHR Farm), Devanahalli, Magadi, Hoskote, Chikkaballapur (Dilkush and Red globe), Yelaburga, Hagari Bommanahalli, Bagalkot (UHS farm) and Indi fall under the soil order Alfisol. Vijaypur pedon of northern dry zone was keyed out as Vertisols whereas, Jamkhandi and Athani as Inceptisols. Properties of Aridisols were observed in B. Bagewadi (Manikchaman and Thompson Seedless) and Afzalpur. Soil fertility status and its mapping using GIS technique revealed that all the nutrients were found to be in adequate range except nitrogen, potassium, zinc, iron, and boron, which indicated the need for application along with organic matter to improve the SOC status. Varieties differed among themselves in yield and plant nutrient composition depending on their age, climatic, soil, and management requirements. Bangalore North (GKVK farm) and Jamkhandi are having medium soil organic carbon stocks of 6.21 and 6.55 kg m⁻³, respectively. Soils of Bangalore North (Rajankunte) were highly suitable (S1) for grapes cultivation. Under northern Karnataka, Vijayapura, B. Bagewadi, Indi, and Afzalpur vineyards were good performers despite the limitations of fertility and free lime content.

Keywords: land characterization, suitability, soil orders, soil organic carbon stock

Procedia PDF Downloads 96
2686 Gadolinium-Based Polymer Nanostructures as Magnetic Resonance Imaging Contrast Agents

Authors: Franca De Sarno, Alfonso Maria Ponsiglione, Enza Torino

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Recent advances in diagnostic imaging technology have significantly contributed to a better understanding of specific changes associated with diseases progression. Among different imaging modalities, Magnetic Resonance Imaging (MRI) represents a noninvasive medical diagnostic technique, which shows low sensitivity and long acquisition time and it can discriminate between healthy and diseased tissues by providing 3D data. In order to improve the enhancement of MRI signals, some imaging exams require intravenous administration of contrast agents (CAs). Recently, emerging research reports a progressive deposition of these drugs, in particular, gadolinium-based contrast agents (GBCAs), in the body many years after multiple MRI scans. These discoveries confirm the need to have a biocompatible system able to boost a clinical relevant Gd-chelate. To this aim, several approaches based on engineered nanostructures have been proposed to overcome the common limitations of conventional CAs, such as the insufficient signal-to-noise ratios due to relaxivity and poor safety profile. In particular, nanocarriers, labeling or loading with CAs, capable of carrying high payloads of CAs have been developed. Currently, there’s no a comprehensive understanding of the thermodynamic contributions enable of boosting the efficacy of conventional CAs by using biopolymers matrix. Thus, considering the importance of MRI in diagnosing diseases, here it is reported a successful example of the next generation of these drugs where the commercial gadolinium chelate is incorporate into a biopolymer nanostructure, formed by cross-linked hyaluronic acid (HA), with improved relaxation properties. In addition, they are highlighted the basic principles ruling biopolymer-CA interactions in the perspective of their influence on the relaxometric properties of the CA by adopting a multidisciplinary experimental approach. On the basis of these discoveries, it is clear that the main point consists in increasing the rigidification of readily-available Gd-CAs within the biopolymer matrix by controlling the water dynamics, the physicochemical interactions, and the polymer conformations. In the end, the acquired knowledge about polymer-CA systems has been applied to develop of Gd-based HA nanoparticles with enhanced relaxometric properties.

Keywords: biopolymers, MRI, nanoparticles, contrast agent

Procedia PDF Downloads 141
2685 Investigation of Heat Conduction through Particulate Filled Polymer Composite

Authors: Alok Agrawal, Alok Satapathy

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In this paper, an attempt to determine the effective thermal conductivity (keff) of particulate filled polymer composites using finite element method (FEM) a powerful computational technique is made. A commercially available finite element package ANSYS is used for this numerical analysis. Three-dimensional spheres-in-cube lattice array models are constructed to simulate the microstructures of micro-sized particulate filled polymer composites with filler content ranging from 2.35 to 26.8 vol %. Based on the temperature profiles across the composite body, the keff of each composition is estimated theoretically by FEM. Composites with similar filler contents are than fabricated using compression molding technique by reinforcing micro-sized aluminium oxide (Al2O3) in polypropylene (PP) resin. Thermal conductivities of these composite samples are measured according to the ASTM standard E-1530 by using the Unitherm™ Model 2022 tester, which operates on the double guarded heat flow principle. The experimentally measured conductivity values are compared with the numerical values and also with those obtained from existing empirical models. This comparison reveals that the FEM simulated values are found to be in reasonable good agreement with the experimental data. Values obtained from the theoretical model proposed by the authors are also found to be in even closer approximation with the measured values within percolation limit. Further, this study shows that there is gradual enhancement in the conductivity of PP resin with increase in filler percentage and thereby its heat conduction capability is improved. It is noticed that with addition of 26.8 vol % of filler, the keff of composite increases to around 6.3 times that of neat PP. This study validates the proposed model for PP-Al2O3 composite system and proves that finite element analysis can be an excellent methodology for such investigations. With such improved heat conduction ability, these composites can find potential applications in micro-electronics, printed circuit boards, encapsulations etc.

Keywords: analytical modelling, effective thermal conductivity, finite element method, polymer matrix composite

Procedia PDF Downloads 308
2684 Improving Knowledge Management Practices in the South African Healthcare System

Authors: Kgabo H. Badimo, Sheryl Buckley

Abstract:

Knowledge is increasingly recognised in this, the knowledge era, as a strategic resource, by public sector organisations, in view of the public sector reform initiatives. People and knowledge play a vital role in attaining improved organisational performance and high service quality. Many government departments in the public sector have started to realise the importance of knowledge management in streamlining their operations and processes. This study focused on knowledge management in the public healthcare service organisations, where the concept of service provider competitiveness pales to insignificance, considering the huge challenges emanating from the healthcare and public sector reforms. Many government departments are faced with challenges of improving organisational performance and service delivery, improving accountability, making informed decisions, capturing the knowledge of the aging workforce, and enhancing partnerships with stakeholders. The purpose of this paper is to examine the knowledge management practices of the Gauteng Department of Health in South Africa, in order to understand how knowledge management practices influence improvement in organisational performance and healthcare service delivery. This issue is explored through a review of literature on dominant views on knowledge management and healthcare service delivery, as well as results of interviews with, and questionnaire responses from, the general staff of the Gauteng Department of Health. Web-based questionnaires, face-to-face interviews and organisational documents were used to collect data. The data were analysed using both the quantitative and qualitative methods. The central question investigated was: To what extent can the conditions required for successful knowledge management be observed, in order to improve organisational performance and healthcare service delivery in the Gauteng Department of Health. The findings showed that the elements of knowledge management capabilities investigated in this study, namely knowledge creation, knowledge sharing and knowledge application, have a positive, significant relationship with all measures of organisational performance and healthcare service delivery. These findings thus indicate that by employing knowledge management principles, the Gauteng Department of Health could improve its ability to achieve its operational goals and objectives, and solve organisational and healthcare challenges, thereby improving organisational.

Keywords: knowledge management, Healthcare Service Delivery, public healthcare, public sector

Procedia PDF Downloads 254
2683 Free Fibular Flaps in Management of Sternal Dehiscence

Authors: H. N. Alyaseen, S. E. Alalawi, T. Cordoba, É. Delisle, C. Cordoba, A. Odobescu

Abstract:

Sternal dehiscence is defined as the persistent separation of sternal bones that are often complicated with mediastinitis. Etiologies that lead to sternal dehiscence vary, with cardiovascular and thoracic surgeries being the most common. Early diagnosis in susceptible patients is crucial to the management of such cases, as they are associated with high mortality rates. A recent meta-analysis of more than four hundred thousand patients concluded that deep sternal wound infections were the leading cause of mortality and morbidity in patients undergoing cardiac procedures. Long-term complications associated with sternal dehiscence include increased hospitalizations, cardiac infarctions, and renal and respiratory failures. Numerous osteosynthesis methods have been described in the literature. Surgical materials offer enough rigidity to support the sternum and can be flexible enough to allow physiological breathing movements of the chest; however, these materials fall short when managing patients with extensive bone loss, osteopenia, or general poor bone quality, for such cases, flaps offer a better closure system. Early utilization of flaps yields better survival rates compared to delayed closure or to patients treated with sternal rewiring and closed drainage. The utilization of pectoralis major flaps, rectus abdominus, and latissimus muscle flaps have all been described in the literature as great alternatives. Flap selection depends on a variety of factors, mainly the size of the sternal defect, infection, and the availability of local tissues. Free fibular flaps are commonly harvested flaps utilized in reconstruction around the body. In cases regarding sternal reconstruction with free fibular flaps, the literature exclusively discussed the flap applied vertically to the chest wall. We present a different technique applying the free fibular triple barrel flap oriented in a transverse manner, in parallel to the ribs. In our experience, this method could have enhanced results and improved prognosis as it contributes to the normal circumferential shape of the chest wall.

Keywords: sternal dehiscence, management, free fibular flaps, novel surgical techniques

Procedia PDF Downloads 80
2682 Status of Physical, Chemical and Biological Attributes of Isheri, Ogun River, in Relation to the Surrounding Anthropogenic Activities of Kara Abattoir, South West Nigeria

Authors: N. B. Ikenweiwe, A. A. Alimi, N. A. Bamidele, A. O. Ewumi, J. Dairo, I. A. Akinnubi, S. O. Otubusin

Abstract:

A study on the physical, chemical and biological parameters of the lower course of Ogun River, Isheri-Olofin was carried out between January and December 2014 in order to determine the effects of the anthropogenic activities of the Kara abattoir and domestic waste depositions on the quality of the water. Water samples were taken twice each month at three selected stations A, B and C (based on characteristic features or activity levels) along the water course. Samples were analysed using standard methods for chemical and biological parameters the same day in the laboratory while physical parameters were determined in-situ with water parameters kit. Generally, results of Transparency, Dissolved Oxygen, Nitrates, TDS and Alkalinity fall below the permissible limits of WHO and FEPA standards for drinking and fish production. Results of phosphates, lead and cadmium were also low but still within the permissible limit. Only Temperature and pH were within limit. Low plankton community, (phytoplankton, zooplankton), which ranges from 3, 5 to 40, 23 were as a result of low levels of DO, transparency and phosphate. The presence of coliform bacteria of public health importance like Escherichia coli, Proteus vulgaris, Aeromonas sp., Shigella sp, Enterobacter aerogenes as well as gram negative bacteria Proteus morganii are mainly indicators of faecal pollution. Fish and other resources obtained from this water stand the risk of being contaminated with these organisms and man is at the receiving end. The results of the physical, chemical and some biological parameters of Isheri, Ogun River, according to this study showed that the live forms of aquatic and fisheries resources there are dwelling under stress as a result of deposition of bones, horns, faecal components, slurry of suspended solids, fat and blood into the water. Government should therefore establish good monitoring system against illegal waste depositions and create education programmes that will enlighten the community on the social, ecological and economic values of the river.

Keywords: water parameters, Isheri Ogun river, anthropogenic activities, Kara abattoir

Procedia PDF Downloads 517
2681 The Relationship between Caregiver Burden and Life Satisfaction of Caregivers of Elderly Individuals

Authors: Guler Duru Asiret, Cemile Kutmec Yilmaz, Gulcan Bagcivan, Tugce Turten Kaymaz

Abstract:

This descriptive study was conducted to determine the relationship between caregiver burden and life satisfaction who give home care to elderly individuals. The sample was recruited from the internal medicine unit and palliative unit of a state hospital located in Turkey on June 2016-2017. The study sample consisted of 231 primary caregiver family member, who met the eligibility criteria and agreed to participate in the study. The inclusion criteria were as follows: inpatient’s caregiver, primary caregiver for at least 3 months, at least 18 years of age, no communication problem or mental disorder. Data were gathered using an Information Form prepared by the researchers based on previous literature, the Zarit Burden Interview (ZBI), and the Satisfaction with Life Scale (SWLS). The data were analyzed using IBM SPSS Statistics software version 20.0 (SPSS, Chicago, IL). The descriptive characteristics of the participant were analyzed using number, percentage, mean and standard deviation. The suitability of normal distribution of scale scores was analyzed using Kolmogorov-Smirnov and Shapiro-Wilk test. Relationships between scales were analyzed using Spearman’s rank-correlation coefficient. P values less than 0.05 were considered to be significant. The average age of the caregivers was 50.11±13.46 (mean±SD) years. Of the caregivers, 76.2% were women, 45% were primary school graduates, 89.2% were married, 38.1% were the daughters of their patients. Among these, 52.4% evaluated their income level to be good. Of them, 53.6% had been giving care less than 2 years. The patients’ average age was 77.1±8.0 years. Of the patients, 55.8% were women, 56.3% were illeterate, 70.6% were married, and 97.4% had at least one chronic disease. The mean Zarit Burden Interview score was 35.4±1.5 and the Satisfaction with Life Scale score was 20.6±6.8. A negative relationship was found between the patients’ score average on the ZBI, and on the SWLS (r= -0.438, p=0.000). The present study determined that the caregivers have a moderate caregiver burden and the life satisfaction. And the life satisfaction of caregivers decreased as their caregiver burden increase. In line with the results obtained from the research, it is recommended that to increase the effectiveness of discharge training, to arrange training and counseling programs for caregivers to cope with the problems they experienced, to monitor the caregivers at regular intervals and to provide necessary institutional support.

Keywords: caregiver burden, family caregivers, nurses, satisfaction

Procedia PDF Downloads 158
2680 Creating an Inclusive Classroom: Country Case Studies Analysis on Mainstream Teachers' Teaching-Efficacy and Attitudes towards Inclusive Education in Japan and Singapore

Authors: Yei Mian Adrian Yap

Abstract:

This study aims to assess the Japanese and Singaporean mainstream teachers’ attitudes and teaching-efficacy towards the inclusion of students with special needs in the regular classrooms by investigating what kind of key variables influence their attitudes and teaching-efficacy. It also further investigates how they strategize to address their challenges to include their students with special needs in their regular classrooms. In order to understand the nature of teachers’ attitudes and teaching-efficacy towards the inclusive education, a mixed-method research methodology was carried out in Japan and Singapore; it involved an explanatory sequential method of employing quantitative research first before qualitative research. In the quantitative research, 189 Japanese and 183 Singaporean teachers were invited to participate in the questionnaires and out of these participants, 38 Japanese and 15 Singaporean teachers shared their views during their semi-structured interviews. Based on the empirical findings, Japanese teachers’ attitudes and teaching-efficacy were more likely to be influenced by their experiences in teaching students with special needs, knowledge about disability legislation, presence of their disabled family members and level of confidence to teach students with special needs. On the other hand, Singaporean teachers’ attitudes and teaching-efficacy were affected by gender, educational level, received trainings in special needs education, knowledge about disability legislation and level of confidence to teach students with special needs. Both country results also demonstrated that there was a positive correlation between their teaching-efficacy and attitude. Narrative findings further expanded the reasons behind these quantitative factors that shaped teachers’ attitudes and teaching-efficacy. Also, it discussed the various problems faced by Japanese and Singaporean teachers and how they identified their coping strategies to circumvent their challenges in including their students with special needs in their regular classrooms. The significance of this research manifests in necessary educational reforms in both countries especially in the context of inclusive education. These findings may not be as definitive as expected but it is believed that it could provide useful information on the current situation about teachers’ concerns towards the inclusive education. In conclusion, this research could potentially make its positive contribution to the body of literature on teachers’ attitudes and teaching-efficacy in the context of Asian developed countries. Further, these findings could posit that regular teachers’ positive attitudes and strong sense of teaching self-efficacy could directly improve the success rate of inclusion of students with special needs in the regular classrooms.

Keywords: attitudes, inclusive education, special education, teaching-efficacy

Procedia PDF Downloads 316
2679 Adequate Dietary Intake to Improve Outcome of Urine: Urea Nitrogen with Balance Nitrogen and Total Lymphocyte Count

Authors: Mardiana Madjid, Nurpudji Astuti Taslim, Suryani As'ad, Haerani Rasyid, Agussalim Bukhari

Abstract:

The high level of Urine Urea Nitrogen (UUN) indicates hypercatabolism occurs in hospitalized patients. High levels of Total Lymphocyte Count (TLC) indicates the immune system condition, adequate wound healing, and limit complication. Adequate dietary intake affects to decrease of hypercatabolism status in treated patient’s hospitals. Nitrogen Balance (NB) is simply the difference between nitrogen (N₂) intake and output. If more N₂ intake than output, then positive NB or anabolic will occur. This study aims to evaluate the effect of dietary intake in influencing balance nitrogen and total lymphocyte count. Method: A total of 43 patients admitted to a Wahidin Sudirohusodo Hospital between 2018 and 2019 for 10 days' treats are included. The inclusion criteria were patients who were treated for 10 days and receives food from the hospital orally. Patients did not experience gastrointestinal disorders such as vomiting and diarrhea and experience impair kidney function and liver function and expressed approval to participate in this study. During hospitalization, food intake, UUN, albumin serum, balance nitrogen, and TLC was assessed twice on day 1 and day 10. There is no Physician Clinical Nutritional intervention to correct food intake. UUN is 24 hours of urine collected on the second day after admission and the tenth day. Statistical analysis uses SPSS 24 with observational cohort methods. Result: The Forty-three participants completed the follow-up (27 men and 18 women). The age of fewer than 4 years is 22 people, 45 to 60 years is 16 people, and over 60 years is 4 people. The result of the study on day 1 obtained SGA score A, SGA score B, SGA score C are 8, 32, 3 until day 10 are 8, 31, 4, respectively. According to 24h dietary recalls, the energy intake during observation was from 522.5 ± 400.4 to 1011.9 ± 545.1 kcal/day P < 0.05, protein intake from 20.07 ± 17.2 to 40.3 ± 27.3 g/day P < 0.05, carbohydrates from 92.5 ± 71.6 to 184.8 ± 87.4 g/day, and fat from 5.5 ± 3.86 to 13.9 ± 13.9 g/day. The UUN during the observation was from 6.6 ± 7.3 to 5.5 ± 3.9 g/day, TLC decreased from 1622.9 ± 897.2 to 1319.9 ± 636.3/mm³ value target 1800/mm³, albumin serum from 3.07 ± 0.76 to 2.9 ± 0.57 g/day, and BN from -7.5 ± 7.2 to -3.1 ± 4.86. Conclusion: The high level of UUN needs to correct adequate dietary intake to improve NB and TLC status on hospitalized patients.

Keywords: adequate dietary intake, balance nitrogen, total lymphocyte count, urine urea nitrogen

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2678 Learning from Flood: A Case Study of a Frequently Flooded Village in Hubei, China

Authors: Da Kuang

Abstract:

Resilience is a hotly debated topic in many research fields (e.g., engineering, ecology, society, psychology). In flood management studies, we are experiencing the paradigm shift from flood resistance to flood resilience. Flood resilience refers to tolerate flooding through adaptation or transformation. It is increasingly argued that our city as a social-ecological system holds the ability to learn from experience and adapt to flood rather than simply resist it. This research aims to investigate what kinds of adaptation knowledge the frequently flooded village learned from past experience and its advantages and limitations in coping with floods. The study area – Xinnongcun village, located in the west of Wuhan city, is a linear village and continuously suffered from both flash flood and drainage flood during the past 30 years. We have a field trip to the site in June 2017 and conducted semi-structured interviews with local residents. Our research summarizes two types of adaptation knowledge that people learned from the past floods. Firstly, at the village scale, it has formed a collective urban form which could help people live during both flood and dry season. All houses and front yards were elevated about 2m higher than the road. All the front yards in the village are linked and there is no barrier. During flooding time, people walk to neighbors through houses yards and boat to outside village on the lower road. Secondly, at individual scale, local people learned tacit knowledge of preparedness and emergency response to flood. Regarding the advantages and limitations, the adaptation knowledge could effectively help people to live with flood and reduce the chances of getting injuries. However, it cannot reduce local farmers’ losses on their agricultural land. After flood, it is impossible for local people to recover to the pre-disaster state as flood emerges during June and July will result in no harvest. Therefore, we argue that learning from past flood experience could increase people’s adaptive capacity. However, once the adaptive capacity cannot reduce people’s losses, it requires a transformation to a better regime.

Keywords: adaptation, flood resilience, tacit knowledge, transformation

Procedia PDF Downloads 322
2677 Adaptive Assemblies: A Scalable Solution for Atlanta's Affordable Housing Crisis

Authors: Claudia Aguilar, Amen Farooq

Abstract:

Among other cities in the United States, the city of Atlanta is experiencing levels of growth that surpass anything we have witnessed in the last century. With the surge of population influx, the available housing is practically bursting at the seams. Supply is low, and demand is high. In effect, the average one-bedroom apartment runs for 1,800 dollars per month. The city is desperately seeking new opportunities to provide affordable housing at an expeditious rate. This has been made evident by the recent updates to the city’s zoning. With the recent influx in the housing market, young professionals, in particular millennials, are desperately looking for alternatives to stay within the city. To remedy Atlanta’s affordable housing crisis, the city of Atlanta is planning to introduce 40 thousand of new affordable housing units by 2026. To achieve the urgent need for more affordable housing, the architectural response needs to adapt to overcome this goal. A method that has proven successful in modern housing is to practice modular means of development. A method that has been constrained to the dimensions of the max load for an eighteen-wheeler. This approach has diluted the architect’s ability to produce site-specific, informed design and rather contributes to the “cookie cutter” stigma that the method has been labeled with. This thesis explores the design methodology for modular housing by revisiting its constructability and adaptability. This research focuses on a modular housing type that could break away from the constraints of transport and deliver adaptive reconfigurable assemblies. The adaptive assemblies represent an integrated design strategy for assembling the future of affordable dwelling units. The goal is to take advantage of a component-based system and explore a scalable solution to modular housing. This proposal aims specifically to design a kit of parts that are made to be easily transported and assembled but also gives the ability to customize the use of components to benefit all unique conditions. The benefits of this concept could include decreased construction time, cost, on-site labor, and disruption while providing quality housing with affordable and flexible options.

Keywords: adaptive assemblies, modular architecture, adaptability, constructibility, kit of parts

Procedia PDF Downloads 68
2676 A Xenon Mass Gauging through Heat Transfer Modeling for Electric Propulsion Thrusters

Authors: A. Soria-Salinas, M.-P. Zorzano, J. Martín-Torres, J. Sánchez-García-Casarrubios, J.-L. Pérez-Díaz, A. Vakkada-Ramachandran

Abstract:

The current state-of-the-art methods of mass gauging of Electric Propulsion (EP) propellants in microgravity conditions rely on external measurements that are taken at the surface of the tank. The tanks are operated under a constant thermal duty cycle to store the propellant within a pre-defined temperature and pressure range. We demonstrate using computational fluid dynamics (CFD) simulations that the heat-transfer within the pressurized propellant generates temperature and density anisotropies. This challenges the standard mass gauging methods that rely on the use of time changing skin-temperatures and pressures. We observe that the domes of the tanks are prone to be overheated, and that a long time after the heaters of the thermal cycle are switched off, the system reaches a quasi-equilibrium state with a more uniform density. We propose a new gauging method, which we call the Improved PVT method, based on universal physics and thermodynamics principles, existing TRL-9 technology and telemetry data. This method only uses as inputs the temperature and pressure readings of sensors externally attached to the tank. These sensors can operate during the nominal thermal duty cycle. The improved PVT method shows little sensitivity to the pressure sensor drifts which are critical towards the end-of-life of the missions, as well as little sensitivity to systematic temperature errors. The retrieval method has been validated experimentally with CO2 in gas and fluid state in a chamber that operates up to 82 bar within a nominal thermal cycle of 38 °C to 42 °C. The mass gauging error is shown to be lower than 1% the mass at the beginning of life, assuming an initial tank load at 100 bar. In particular, for a pressure of about 70 bar, just below the critical pressure of CO2, the error of the mass gauging in gas phase goes down to 0.1% and for 77 bar, just above the critical point, the error of the mass gauging of the liquid phase is 0.6% of initial tank load. This gauging method improves by a factor of 8 the accuracy of the standard PVT retrievals using look-up tables with tabulated data from the National Institute of Standards and Technology.

Keywords: electric propulsion, mass gauging, propellant, PVT, xenon

Procedia PDF Downloads 331
2675 Critical Parameters of a Square-Well Fluid

Authors: Hamza Javar Magnier, Leslie V. Woodcock

Abstract:

We report extensive molecular dynamics (MD) computational investigations into the thermodynamic description of supercritical properties for a model fluid that is the simplest realistic representation of atoms or molecules. The pair potential is a hard-sphere repulsion of diameter σ with a very short attraction of length λσ. When λ = 1.005 the range is so short that the model atoms are referred to as “adhesive spheres”. Molecular dimers, trimers …etc. up to large clusters, or droplets, of many adhesive-sphere atoms are unambiguously defined. This then defines percolation transitions at the molecular level that bound the existence of gas and liquid phases at supercritical temperatures, and which define the existence of a supercritical mesophase. Both liquid and gas phases are seen to terminate at the loci of percolation transitions, and below a second characteristic temperature (Tc2) are separated by the supercritical mesophase. An analysis of the distribution of clusters in gas, meso- and liquid phases confirms the colloidal nature of this mesophase. The general phase behaviour is compared with both experimental properties of the water-steam supercritical region and also with formally exact cluster theory of Mayer and Mayer. Both are found to be consistent with the present findings that in this system the supercritical mesophase narrows in density with increasing T > Tc and terminates at a higher Tc2 at a confluence of the primary percolation loci. The expended plot of the MD data points in the mesophase of 7 critical and supercritical isotherms in highlight this narrowing in density of the linear-slope region of the mesophase as temperature is increased above the critical. This linearity in the mesophase implies the existence of a linear combination rule between gas and liquid which is an extension of the Lever rule in the subcritical region, and can be used to obtain critical parameters without resorting to experimental data in the two-phase region. Using this combination rule, the calculated critical parameters Tc = 0.2007 and Pc = 0.0278 are found be agree with the values found by of Largo and coworkers. The properties of this supercritical mesophase are shown to be consistent with an alternative description of the phenomenon of critical opalescence seen in the supercritical region of both molecular and colloidal-protein supercritical fluids.

Keywords: critical opalescence, supercritical, square-well, percolation transition, critical parameters.

Procedia PDF Downloads 504
2674 Experiences of Social Participation among Community Elderly with Mild Cognitive Impairment: A Qualitative Research

Authors: Xue Li, Hui Xu

Abstract:

Mild cognitive impairment (MCI) is a clinical stage that occurs between normal aging and dementia. Although MCI increases the risk of developing dementia, individuals with MCI may maintain stable cognitive function and even recover to a typical cognitive state. An intervention to prevent or delay the progression to dementia in individuals with MCI may involve promoting social engagement. Social participation is the engagement in socially relevant social exchanges and meaningful activities. Older adults with MCI may encounter restricted cognitive abilities, mood changes, and behavioral difficulties during social participation, influencing their willingness to engage. Therefore, this study aims to employ qualitative research methods to gain an in-depth comprehension of the authentic social participation experiences of older adults with mild cognitive impairment, which will establish a foundation for designing appropriate intervention programs. A phenomenological research was conducted. The study participants were selected using the purposive sampling method in combination with the maximum differentiation sampling strategy. Face-to-face semistructured interviews were conducted among 12 elderly individuals suffering from mild cognitive impairment in a community in Zhengzhou City from May to July 2023. Colaizzi 7-step method was used to analyze the data and extract the theme. The real experience of social participation in older adults with mild cognitive impairment can be summarized into 3 themes: (1) a single social relationship but a strong desire to participate, (2) a dual experience of social participation with both positive and negative aspects, (3) multiple barriers to social participation, including impaired memory capacity, heavy family responsibilities and lack of infrastructure. The study found that elderly individuals with mild cognitive impairment and one social interaction display an increased desire to engage in society. To improve social participation levels and reduce cognitive function decline, healthcare providers should work with relevant government agencies and the community to create a comprehensive social participation system. It is important for healthcare providers to note the social participation status of the elderly with mild cognitive impairment.

Keywords: mild cognitive impairment, the elderly, social participation, qualitative research

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2673 Utilization and Proximate Composition of Nile Tilapia, Common Carp and African Mudfish Polycultured in Fertilized Ponds

Authors: I. A. Yola

Abstract:

Impact of poultry dropping, cow dung and rumen content on utilization and proximate composition of Oreochromis niliticus, Clarias gariepinus and Cyprinus capio in a polyculture system were studied. The research was conducted over a period of 52 weeks. Poultry droppings (PD), cow dung (CD) and rumen content (RC) were applied at three levels 30g,60g and 120g/m2/week, 25g,50g and 100g/m2/week and 22g, 44g and 88g/m2/week treatment, respectively. The control only conventional feed with 40% CP without manure application was used. Physicochemical and biological properties measured were higher in manure pond than control. The difference was statistically significant (P < 0.05) between and within treatments with exception of temperature with a combined mean of 27.900C. The water was consistently alkaline with mean values for pH of 6.61, transparency 22.6cm, conductivity 35.00µhos/cm, dissolved oxygen 4.6 mg/l, biological oxygen demand 2.8mg/l, nitrate and phosphates 0.9mg/l and 0.35mg/l, respectively. The three fish species increase in weight with increased manure rate, with a higher value in PD treatment on C. capio record 340g, O. niloticus weighed 310g and C. gariepinus 280g over the experimental period. Fishes fed supplementary diet (control) grew bigger with highest value on C. capio (685g) O. niloticus (620g) and then C. gariepinus (526g). The differences were statistically significant (P < 0.05). The result of whole body proximate analysis indicated that various manures and rates had an irregular pattern on the protein and ash gain per 100g of fish body weight gain. The combined means for whole fish carcass protein, lipids, moisture, ash and gross energy were 11.84, 2.43, 74.63, 3.00 and 109.9 respectively. The notable exceptions were significant (p < 0.05) increases in body fat and gross energy gains in all fish species accompanied by decreases in percentages of moisture as manure rates increased. Survival percentage decreases from 80% to 70%. It is recommended to use poultry dropping as manure/feeds at the rate of 120kg/ha/week for good performances in polyculture.

Keywords: organic manure, Nile tilapia, African mud fish, common carp, proximate composition

Procedia PDF Downloads 540
2672 An Analysis of Pick Travel Distances for Non-Traditional Unit Load Warehouses with Multiple P/D Points

Authors: Subir S. Rao

Abstract:

Existing warehouse configurations use non-traditional aisle designs with a central P/D point in their models, which is mathematically simple but less practical. Many warehouses use multiple P/D points to avoid congestion for pickers, and different warehouses have different flow policies and infrastructure for using the P/D points. Many warehouses use multiple P/D points with non-traditional aisle designs in their analytical models. Standard warehouse models introduce one-sided multiple P/D points in a flying-V warehouse and minimize pick distance for a one-way travel between an active P/D point and a pick location with P/D points, assuming uniform flow rates. A simulation of the mathematical model generally uses four fixed configurations of P/D points which are on two different sides of the warehouse. It can be easily proved that if the source and destination P/D points are both chosen randomly, in a uniform way, then minimizing the one-way travel is the same as minimizing the two-way travel. Another warehouse configuration analytically models the warehouse for multiple one-sided P/D points while keeping the angle of the cross-aisles and picking aisles as a decision variable. The minimization of the one-way pick travel distance from the P/D point to the pick location by finding the optimal position/angle of the cross-aisle and picking aisle for warehouses having different numbers of multiple P/D points with variable flow rates is also one of the objectives. Most models of warehouses with multiple P/D points are one-way travel models and we extend these analytical models to minimize the two-way pick travel distance wherein the destination P/D is chosen optimally for the return route, which is not similar to minimizing the one-way travel. In most warehouse models, the return P/D is chosen randomly, but in our research, the return route P/D point is chosen optimally. Such warehouses are common in practice, where the flow rates at the P/D points are flexible and depend totally on the position of the picks. A good warehouse management system is efficient in consolidating orders over multiple P/D points in warehouses where the P/D is flexible in function. In the latter arrangement, pickers and shrink-wrap processes are not assigned to particular P/D points, which ultimately makes the P/D points more flexible and easy to use interchangeably for picking and deposits. The number of P/D points considered in this research uniformly increases from a single-central one to a maximum of each aisle symmetrically having a P/D point below it.

Keywords: non-traditional warehouse, V cross-aisle, multiple P/D point, pick travel distance

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2671 Suitability of Satellite-Based Data for Groundwater Modelling in Southwest Nigeria

Authors: O. O. Aiyelokun, O. A. Agbede

Abstract:

Numerical modelling of groundwater flow can be susceptible to calibration errors due to lack of adequate ground-based hydro-metrological stations in river basins. Groundwater resources management in Southwest Nigeria is currently challenged by overexploitation, lack of planning and monitoring, urbanization and climate change; hence to adopt models as decision support tools for sustainable management of groundwater; they must be adequately calibrated. Since river basins in Southwest Nigeria are characterized by missing data, and lack of adequate ground-based hydro-meteorological stations; the need for adopting satellite-based data for constructing distributed models is crucial. This study seeks to evaluate the suitability of satellite-based data as substitute for ground-based, for computing boundary conditions; by determining if ground and satellite based meteorological data fit well in Ogun and Oshun River basins. The Climate Forecast System Reanalysis (CFSR) global meteorological dataset was firstly obtained in daily form and converted to monthly form for the period of 432 months (January 1979 to June, 2014). Afterwards, ground-based meteorological data for Ikeja (1981-2010), Abeokuta (1983-2010), and Oshogbo (1981-2010) were compared with CFSR data using Goodness of Fit (GOF) statistics. The study revealed that based on mean absolute error (MEA), coefficient of correlation, (r) and coefficient of determination (R²); all meteorological variables except wind speed fit well. It was further revealed that maximum and minimum temperature, relative humidity and rainfall had high range of index of agreement (d) and ratio of standard deviation (rSD), implying that CFSR dataset could be used to compute boundary conditions such as groundwater recharge and potential evapotranspiration. The study concluded that satellite-based data such as the CFSR should be used as input when constructing groundwater flow models in river basins in Southwest Nigeria, where majority of the river basins are partially gaged and characterized with long missing hydro-metrological data.

Keywords: boundary condition, goodness of fit, groundwater, satellite-based data

Procedia PDF Downloads 112