Search results for: saturation index
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3909

Search results for: saturation index

2889 Role of Interlukin-18 in Primary Knee Osteoarthritis: Clinical, Laboratory and Radiological Study

Authors: Ibrahim Khalil Ibrahim, Enas Mohamed Shahine, Abeer Shawky El Hadedy, Emmanuel Kamal Aziz Saba, Ghada Salah Attia Hussein

Abstract:

Osteoarthritis (OA) is a multifactorial disease characterized by a progressive degradation of articular cartilage and is the leading cause of disability in elderly persons. IL-18 contributes to the destruction of cartilage and bone in the disease process of arthritis. The aim of the study was to investigate the role of IL-18 in primary knee OA patients. Serum level of IL-18 was assessed by enzyme-linked immunosorbent assay in 30 primary knee OA patients and compared to 20 age and gender-matched healthy volunteers as a control group. Radiographic severity of OA was assessed by Kellgren and Lawrence (KL) global scale. Pain, stiffness and functional assessment were done using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). OA patients had significantly higher serum IL-18 level than in control group (420.93 ± 345.4 versus 151.03 ± 144.16 pg/ml, P=0.001). Serum level of IL-18 was positively correlated with KL global scale (P=0.001). There were no statistically significant correlations between serum level of IL-18 and pain, stiffness, function subscales and total WOMAC index scores among the studied patients. In conclusions, IL-18 has a role in the pathogenesis of OA and it is positively correlated with the radiographic damage of OA.

Keywords: Interlukin-18, knee osteoarthritis, primary osteoarthritis, WOMAC scale

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2888 Cultural Approach to Batak Toba Folklore

Authors: Maritess A. Rulona

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Cultural appropriation on traditional symbols has been a worldwide problem. Indonesia’s Batak Toba, an indigenous people group has experienced such appropriation. Bataknese has rich cultural heritage and oral traditions. Their cultural symbols originated from their folklores namely myths, legends, and folktales. This research used both oral traditions and cultural symbols of Batak Toba for a comparative analysis of their ancient and modern practices. This is anchored on Franz Boas’ Cultural Relativism in analyzing their five common cultural symbols. Further, it also utilized Stith Thompson’s Motif-Index to determine the common motif evident in their ten folklores. Ten Batak Toba key respondents provided information in this study. Some informants were also featured in the 20-minute documentary of this study. Thus, the findings were: 1) Traditional customs such as weddings, burial, and reburial are still observed using their cultural symbols; 2) The five most common cultural symbols are Ulos Ragidup, Sigale Gale, Rumah Bolon, Lake Toba, and Gondang; and 3) Batak culture values animals such as buffalo, lizard, and goldfish since they have ancient beliefs of mythical creatures; In conclusion, this study proved that there is a clear connection between the tribe’s oral traditions and cultural symbols. With these findings, this study recommends that elder Bataks teach younger Batak to be immersed in the cultural practices and to incorporate their traditional practices in their modern events.

Keywords: batak toba, cultural appropriation, motif-index, oral tradition, cultural emblems

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2887 Interannual Variations in Snowfall and Continuous Snow Cover Duration in Pelso, Central Finland, Linked to Teleconnection Patterns, 1944-2010

Authors: M. Irannezhad, E. H. N. Gashti, S. Mohammadighavam, M. Zarrini, B. Kløve

Abstract:

Climate warming would increase rainfall by shifting precipitation falling form from snow to rain, and would accelerate snow cover disappearing by increasing snowpack. Using temperature and precipitation data in the temperature-index snowmelt model, we evaluated variability of snowfall and continuous snow cover duration(CSCD) during 1944-2010 over Pelso, central Finland. MannKendall non-parametric test determined that annual precipitation increased by 2.69 (mm/year, p<0.05) during the study period, but no clear trend in annual temperature. Both annual rainfall and snowfall increased by 1.67 and 0.78 (mm/year, p<0.05), respectively. CSCD was generally about 205 days from 14 October to 6 May. No clear trend was found in CSCD over Pelso. Spearman’s rank correlation showed most significant relationships of annual snowfall with the East Atlantic (EA) pattern, and CSCD with the East Atlantic/West Russia (EA/WR) pattern. Increased precipitation with no warming temperature caused the rainfall and snowfall to increase, while no effects on CSCD.

Keywords: variations, snowfall, snow cover duration, temperature-index snowmelt model, teleconnection patterns

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2886 Optimization of Surface Roughness in Additive Manufacturing Processes via Taguchi Methodology

Authors: Anjian Chen, Joseph C. Chen

Abstract:

This paper studies a case where the targeted surface roughness of fused deposition modeling (FDM) additive manufacturing process is improved. The process is designing to reduce or eliminate the defects and improve the process capability index Cp and Cpk for an FDM additive manufacturing process. The baseline Cp is 0.274 and Cpk is 0.654. This research utilizes the Taguchi methodology, to eliminate defects and improve the process. The Taguchi method is used to optimize the additive manufacturing process and printing parameters that affect the targeted surface roughness of FDM additive manufacturing. The Taguchi L9 orthogonal array is used to organize the parameters' (four controllable parameters and one non-controllable parameter) effectiveness on the FDM additive manufacturing process. The four controllable parameters are nozzle temperature [°C], layer thickness [mm], nozzle speed [mm/s], and extruder speed [%]. The non-controllable parameter is the environmental temperature [°C]. After the optimization of the parameters, a confirmation print was printed to prove that the results can reduce the amount of defects and improve the process capability index Cp from 0.274 to 1.605 and the Cpk from 0.654 to 1.233 for the FDM additive manufacturing process. The final results confirmed that the Taguchi methodology is sufficient to improve the surface roughness of FDM additive manufacturing process.

Keywords: additive manufacturing, fused deposition modeling, surface roughness, six-sigma, Taguchi method, 3D printing

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2885 High Harmonics Generation in Hexagonal Graphene Quantum Dots

Authors: Armenuhi Ghazaryan, Qnarik Poghosyan, Tadevos Markosyan

Abstract:

We have considered the high-order harmonic generation in-plane graphene quantum dots of hexagonal shape by the independent quasiparticle approximation-tight binding model. We have investigated how such a nonlinear effect is affected by a strong optical wave field, quantum dot typical band gap and lateral size, and dephasing processes. The equation of motion for the density matrix is solved by performing the time integration with the eight-order Runge-Kutta algorithm. If the optical wave frequency is much less than the quantum dot intrinsic band gap, the main aspects of multiphoton high harmonic emission in quantum dots are revealed. In such a case, the dependence of the cutoff photon energy on the strength of the optical pump wave is almost linear. But when the wave frequency is comparable to the bandgap of the quantum dot, the cutoff photon energy shows saturation behavior with an increase in the wave field strength.

Keywords: strong wave field, multiphoton, bandgap, wave field strength, nanostructure

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2884 Laboratory Testing Regime for Quantifying Soil Collapsibility

Authors: Anne C. Okwedadi, Samson Ng’ambi, Ian Jefferson

Abstract:

Collapsible soils go through radical rearrangement of their particles when triggered by water, stress or/and vibration, causing loss of volume. This loss of volume in soil as seen in foundation failures has caused millions of dollars’ worth of damages to public facilities and infrastructure and so has an adverse effect on the society and people. Despite these consequences and the several studies that are available, more research is still required in the study of soil collapsibility. Discerning the pedogenesis (formation) of soils and investigating the combined effects of the different geological soil properties is key to elucidating and quantifying soils collapsibility. This study presents a novel laboratory testing regime that would be undertaken on soil samples where the effects of soil type, compactive variables (moisture content, density, void ratio, degree of saturation) and loading are analyzed. It is anticipated that results obtained would be useful in mapping the trend of the combined effect thus the basis for evaluating soil collapsibility or collapse potentials encountered in construction with volume loss problems attributed to collapse.

Keywords: collapsible soil, geomorphological process, soil collapsibility properties, soil test

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2883 Effects of Dietary Polyunsaturated Fatty Acids and Beta Glucan on Maturity, Immunity, and Fry Quality of Pabdah Catfish, Ompok pabda

Authors: Zakir Hossain, Saddam Hossain

Abstract:

A nutritionally balanced diet and selection of appropriate species are important criteria in aquaculture. The present study was conducted to evaluate the effects of polyunsaturated fatty acids (PUFAs) and beta glucan-containing diets on growth performance, feed utilization, maturation, immunity, early embryonic and larval development of endangered Pabdah catfish, Ompok pabda. In this study, squid extracted lipids and mushroom powder were used as the source of PUFAs and beta-glucan, respectively, and formulated two isonitrogenous diets such as a basal or control (CON) diet and a treated (PBG) diet with maintaining 30% protein levels. During the study period, similar physicochemical conditions of water such as temperature, pH, and dissolved oxygen (DO) were 26.5±2 °C, 7.4±0.2, and 6.7±0.5 ppm, respectively, in each cistern. The results showed that final mean body weight, final mean length gain, food conversion ratio (FCR), specific growth rate (SGR), food conversion efficiency (%), hepato somatic index (HSI), kidney index (KI), and viscerosomatic index (VSI) were significantly (P<0.01 and P<0.05) higher in fish fed the PBG diet than that of fish fed the CON diet. The length-weight relationship and relative condition factor (K) of O. pabda were significantly (P<0.05) affected by the PBG diet. The gonadosomatic index (GSI), sperm viability, blood serum calcium ion concentrations (Ca²⁺), and vitellogenin level were significantly (P<0.05) higher in fish fed the PBG diet than that of fish fed the CON diet; which was used to the indication of fish maturation. During the spawning season, lipid granules and normal morphological structure were observed in the treated fish liver, whereas fewer lipid granules of liver were observed in the control group. Based on the immunity and stress resistance-related parameters such as hematological indices, antioxidant activity, lysozyme level, respiratory burst activity, blood reactive oxygen species (ROS), complement activity (ACH50 assay), specific IgM, brain AChE, plasma PGOT, and PGPT enzyme activity were significantly (P<0.01 and P<0.05) higher in fish fed the PBG diet than that of fish fed the CON diet. The fecundity, fertilization rate (92.23±2.69%), hatching rate (87.43±2.17 %), and survival (76.62±0.82%) of offspring were significantly higher (P˂0.05) in the PBG diet than in control. Consequently, early embryonic and larval development was better in PBG treated group than in control. Therefore, the present study showed that the polyunsaturated fatty acids (PUFAs) and beta-glucan enriched experimental diet were more effective and achieved better growth, feed utilization, maturation, immunity, and spawning performances of O. pabda.

Keywords: lipids, beta-glucan, fish maturity, fish immunity

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2882 Microbiota Associated With the Larval Culture of Red Cusk Eel Genipterus Chilensis in Chile

Authors: Luz Hurtado, Rodrigo Rojas, Jaime Romero, Christopher Concha

Abstract:

The culture of the marine fish red cusk eel Genypterus chilensis is currently considered a priority for Chilean aquaculture which is a Chilean native species of high gastronomic demand and market value. The microbiota was analyzed in terms of diversity and structure using massive Illumina sequencing. The analysis of alpha diversity was performed in samples of G. chilensis larvae of 6, 18 and 32 dph (days post-hatching) and it was observed that there were significant differences (P = 0.05) between the days of culture for the Chao1 index, being the larvae of 18 dph the one with the highest index followed by the larvae of 6 dph, The lowest value for this index was presented in larvae of 32 dph. There were no significant differences in larvae between the days of culture for the Shannon (P=0.0857) and Simpson (P=0.0714) indices. In general, the larvae of G. chilensis have high rates of diversity. When analyzing the beta diversity, a differentiation between the bacterial communities is observed depending on the day of the culture of the larvae. Considering the PCoA elaborated from the unweighted UniFrac statistic, the explained variance was 46.2% (PC1 29.2% and PC2 17.0%) and in the case of the PCoA elaborated with the weighted UniFrac statistic; the explained variance was 65.5% (PC1 41.8% and PC2 23.7%) these differences were significant based on the Permanova statistical analysis (P= 0.002 and 0.037 respectively). When analyzing the taxonomic composition of the microbiota of the larvae in the different days of culture it was observed that at the phyla level the most abundant in the larvae of 6 dph were Proteobacteria (57%) Verrucomicrobia (24%) and Firmicutes (14%), for the larvae of 18 dph the predominant phyla were Proteobacteria (90%), Dependientiae (5%), Actinobacteria (2%) and Plactomyces (2%), for the larvae of 32 dph the phyla that presented the highest relative abundance were Proteobacteria (57%), Firmicutes (29%), Verrucomicrobia (5%) and Actinobacteria (5%), when comparing the larvae between the days it was observed that the phylum Proteobacteria was the most abundant in the samples of larvae of 6, 18 and 32 dph being the larvae of 18 dph those that present the highest relative abundance, the larvae of 6 dph were those that presented the highest relative abundance for the phylum Verrucomicrobia and in the larvae of 32 dph was observed greater abundance of the phylum Firmicutes compared to the other days of larval culture. At the level of genera, those with the highest relative abundance in larvae of 6 dph were Rubritalea (30%), Psychrobacter (28%), staphylococcus (17%) and Ralstonia (10%), for the larvae of 18 dph the genera with the highest abundance were Psychrobacter (47%), Litoreibacter (13%), Nautella (9%) and Cohesibacter (8%), for the larvae of 32 dph the most abundant genera were Alloiococcus (25%), Dialister (14%), Neptunomonas (13%) and Piscirickettsia (11%). When observing the taxonomic composition of the larvae between the days of larval culture, it is observed that there are differences between them.

Keywords: microbiota, diversity, G. Chilensis, larvae

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2881 Endothelial Progenitor Cell Biology in Ankylosing Spondylitis

Authors: Ashit Syngle, Inderjit Verma, Pawan Krishan

Abstract:

Aim: Endothelial progenitor cells (EPCs) are unique populations which have reparative potential in overcoming the endothelial damage and reducing cardiovascular risk. Patients with ankylosing spondylitis (AS) have increased risk of cardiovascular morbidity and mortality. The aim of this study was to investigate the endothelial progenitor cell population in AS patients and its potential relationships with disease variables. Methods: Endothelial progenitor cells were measured in peripheral blood samples from 20 AS and 20 healthy controls by flow cytometry on the basis of CD34 and CD133 expression. Disease activity was evaluated by using Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Functional ability was monitored by using Bath Ankylosing Spondylitis Functional Index (BASFI). Results: EPCs were depleted in AS patients as compared to the healthy controls (CD34+/CD133+: 0.027 ± 0.010 % vs. 0.044 ± 0.011 %, p<0.001). EPCs depletion were significantly associated with disease duration (r=-0.52, p=0.01) and BASDAI (r=-0.45, p=0.04). Conclusion: This is the first study to demonstrate endothelial progenitor cells depletion in AS patients. EPCs depletion inversely correlates with disease duration and disease activity, suggesting the pivotal role of inflammation in depletion of EPCs. EPC would possibly also serve as a therapeutic target for preventing cardiovascular disease in AS.

Keywords: ankylosing spondylitis, endothelial progenitor cells, inflammation, vascular damage

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2880 Modelling of Reactive Methodologies in Auto-Scaling Time-Sensitive Services With a MAPE-K Architecture

Authors: Óscar Muñoz Garrigós, José Manuel Bernabeu Aubán

Abstract:

Time-sensitive services are the base of the cloud services industry. Keeping low service saturation is essential for controlling response time. All auto-scalable services make use of reactive auto-scaling. However, reactive auto-scaling has few in-depth studies. This presentation shows a model for reactive auto-scaling methodologies with a MAPE-k architecture. Queuing theory can compute different properties of static services but lacks some parameters related to the transition between models. Our model uses queuing theory parameters to relate the transition between models. It associates MAPE-k related times, the sampling frequency, the cooldown period, the number of requests that an instance can handle per unit of time, the number of incoming requests at a time instant, and a function that describes the acceleration in the service's ability to handle more requests. This model is later used as a solution to horizontally auto-scale time-sensitive services composed of microservices, reevaluating the model’s parameters periodically to allocate resources. The solution requires limiting the acceleration of the growth in the number of incoming requests to keep a constrained response time. Business benefits determine such limits. The solution can add a dynamic number of instances and remains valid under different system sizes. The study includes performance recommendations to improve results according to the incoming load shape and business benefits. The exposed methodology is tested in a simulation. The simulator contains a load generator and a service composed of two microservices, where the frontend microservice depends on a backend microservice with a 1:1 request relation ratio. A common request takes 2.3 seconds to be computed by the service and is discarded if it takes more than 7 seconds. Both microservices contain a load balancer that assigns requests to the less loaded instance and preemptively discards requests if they are not finished in time to prevent resource saturation. When load decreases, instances with lower load are kept in the backlog where no more requests are assigned. If the load grows and an instance in the backlog is required, it returns to the running state, but if it finishes the computation of all requests and is no longer required, it is permanently deallocated. A few load patterns are required to represent the worst-case scenario for reactive systems: the following scenarios test response times, resource consumption and business costs. The first scenario is a burst-load scenario. All methodologies will discard requests if the rapidness of the burst is high enough. This scenario focuses on the number of discarded requests and the variance of the response time. The second scenario contains sudden load drops followed by bursts to observe how the methodology behaves when releasing resources that are lately required. The third scenario contains diverse growth accelerations in the number of incoming requests to observe how approaches that add a different number of instances can handle the load with less business cost. The exposed methodology is compared against a multiple threshold CPU methodology allocating/deallocating 10 or 20 instances, outperforming the competitor in all studied metrics.

Keywords: reactive auto-scaling, auto-scaling, microservices, cloud computing

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2879 Assessment of Oral and Dental Health Status of Pregnant Women in Malaga, Spain

Authors: Nepton Kiani

Abstract:

Dental decay is one of the most common chronic diseases worldwide and imposes significant costs annually on people and healthcare systems. Addressing this issue is among the important programs of the World Health Organization in the field of oral and dental disease prevention and health promotion. In this context, oral and dental health in vulnerable groups, especially pregnant women, is of greater importance due to the health maintenance of the mother and fetus. The aim of this study is to investigate the DMFT index and various factors affecting it in order to identify different factors influencing the process of dental decay and to take an effective step in reducing the progression of this disease, control, and prevention. In this cross-sectional descriptive study, 120 pregnant women attending Nepton Policlinica clinic in Malaga, Spain, were evaluated for the DMFT index and oral and dental hygiene. In this regard, interviews, precise observations, and data collection were used. Subsequently, data analysis was performed using SPSS software and employing correlation tests, Kruskal-Wallis, and Mann-Whitney tests. The DMFT index for pregnant women in three age groups 22-26, 27- 31, and 32-36 years was respectively 2.8, 4.5, and 5.6. The results of logistic regression analysis showed that demographic variables (age, education, job, economic status) and the frequency of brushing and flossing lead to preventive behavior up to 49.58 percent (P<0.05). Generally, the results indicated that oral and dental care during pregnancy is poor. Only a small number of pregnant women regularly used toothbrush and dental floss or visited the dentist regularly. On the other hand, poor performance in adopting oral and dental care was more observed in pregnant women with lower economic and educational status. The present study showed that raising the level of awareness and education on oral and dental health in pregnant women is essential. In this field, it is necessary to focus on conducting educational-care courses at the level of healthcare centers for midwives, healthcare personnel, and at the community level for families, to prevent and perform dental treatments before the pregnancy period

Keywords: Malaga, oral and dental health, pregnant women, Spain

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2878 The Effect of Surgical Intervention on Pediatric and Adolescent Obstructive Sleep Apnea Syndrome

Authors: Ching-Yi Yiu, Hui-Chen Hsu

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Objectives: Obstructive sleep apnea syndrome (OSAS) is a popular problem in the modern society. It usually leads to sleep disorder, excessive daytime sleepiness and associated with cardiovascular diseases, cognitive dysfunction and even death. The nonsurgical therapies include continuous positive airway pressure (CPAP), diet and oral appliances. The surgical approaches have nasal surgery, tonsillectomy, adenoidectomy, uvulopalatopharyngoplasty (UPPP) and transoral robotic surgery (TORS).We compare the impact of surgical treatments on these kinds of patients. Methods: Between January 2018 to September 2022, We have enrolled 125 OSAS patients including 82 male and 43 female in Chi Mei Medical Center, Liouying, Taiwan. The age distribution from 6 to 71 years old (y/o) with mean age 36.1 y/o. The averaged body mass index (BMI) is 25 kg/m2 in male and 25.5 kg/m2 in female. In this cohort, we evaluated their upper airway obstruction sites with nasopharyngoscopy and scheduled a planned surgery. Some of cases received polysomnography (PSG) preoperatively, the averaged apnea-hypopnea index (AHI) is 37.7 events/hour. We have 68 patients received tonsillectomy, 9 received UPPP, 42 received UPPP and septomeatoplasty (SMP) and 6 received adenoidectomy and tonsillectomy (A and T). The subjective daytime sleepiness was evaluated with the Epworth sleepiness scale (ESS). Results: In the 68 tonsillectomy group, the averaged BMI is 24.9 kg/m2. In the UPPP group, the averaged BMI is 28.9 kg/m2. In UPPP and SMP group, the averaged BMI is 27.9 kg/m2. In the A and T group, the averaged BMI is 17.2 kg/m2. The reduction of AHI less than 20 is 58% postoperatively. The ESS reduced from 10.9 to 4.9 after surgery. Conclusion: Obstructive sleep apnea syndrome is a common upper airway disturbance in the general population. The prevalence rate is ranging high depending on different regions, age, sex and race. It leads to severe morbidity and mortality including car accident, stroke, nocturnal desaand sudden death and should be considered to be a major public health problem. The CPAP is effective to improve daytime sleepiness but the long-term compliance is low. The surgical treatment with different modalities can produce 50% decrease in AHI and ESS after surgery in the 6 to 12 months short-term period.

Keywords: apnea-hypopnea index, obstructive sleep apnea syndrome, polysomnography, uvulopalatopharyngoplasty

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2877 Analysis and Study of Phytoplankton and the Environmental Characteristics of Tarkwa Bay, Lagos, South-Western, Nigeria

Authors: Bukola Dawodu, Charles Onyema

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The phytoplankton and environmental characteristics of Tarkwa Bay, Lagos in South-western Nigeria were investigated from January to June 2012. Environmental characteristics within the Bay were largely determined by floodwater inflow in the wet months (April – June) and increased tidal marine conditions in the dry months (January – March). Similarly, rainfall distribution and possibly tidal seawater inflow were the key factors that govern the variation in phytoplankton distribution, species diversity, chlorophyll a concentration and environmental characteristics of the bay. Values for physico-chemical parameters were indicative of high levels of fluctuations inwards from the East mole towards Tarkwa Bay (e.g. T.S.S > 11mg/L, T.D.S > 33541.0mg/L, D.O. < 5.4). Chlorophyll A values did not show any discernable pattern and correlated negatively with total dissolved solids and total suspended solids (r = -0.27 and -0.04) as both were inconsistent throughout the study period. Four phytoplankton divisions were observed throughout the sampling period with the Bacillariophyta (diatoms) being the dominant group followed by Dinophyta (dinoflagellates), Cyanophyta (the blue-green algae) and Chlorophyta (the green algae). A total of twenty-one species from nine genera were recorded during the period of study. Diatoms formed the most abundant group making fifteen species from five genera. The centric forms dominated over the pennates in the diatom group with Skeletonema sp. Chaetoceros spp. and Coscinodiscus spp. being the dominant centric diatoms while Navicula spp. was the more dominant pennate form. The Dinoflagellates were represented by six species from one genus, the blue-green algae with five species from two genera while the green algae had one species from one genus. Comparatively, total biomass was more in the dry months (Jan. - Mar.) and decreased in the 'wet months' (Apr. – Jun.). Species diversity (S), Shannon Wiener index (Hs), Margalef Index (d) and Equitability Index (j) values were higher during the dry months while reduced value marked the wet months possibly as a result of dilution of rain effects. Outcomes of bio-indices variations were reflections of the degree of occurrence and abundance of species linked to seasons operating in the study site.

Keywords: coastal waters, phytoplankton, species abundance, ecosystems

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2876 Measuring the Quality of Business Education: Employment Readiness Assessment

Authors: Gulbakhyt Sultanova

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Business education institutions assess the progress of their students by giving them grades for courses completed and calculating a Grade Point Average (GPA). Whether the participation in these courses has led to the development of competences enabling graduates to successfully compete in the labor market should be measured using a new index: Employment Readiness Assessment (ERA). The higher the ERA, the higher the quality of education at a business school. This is applied, empirical research conducted by using a method of linear optimization. The aim of research is to identify factors which lead to the minimization of the deviation of GPA from ERA as well as to the maximization of ERA. ERA is composed of three components resulting from testing proficiency in Business English, testing work and personal skills, and job interview simulation. The quality of education is improving if GPA approximates ERA and ERA increases. Factors which have had a positive effect on quality enhancement are academic mobility of students and staff, practical-oriented courses taught by staff with work experience, and research-based courses taught by staff with research experience. ERA is a better index to measure the quality of business education than traditional indexes such as GPA due to its greater accuracy in assessing the level of graduates’ competences demanded in the labor market. Optimizing the educational process in pursuit of quality enhancement, ERA has to be used in parallel with GPA to find out which changes worked and resulted in improvement.

Keywords: assessment and evaluation, competence evaluation, education quality, employment readiness

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2875 A Conceptual Framework of Integrated Evaluation Methodology for Aquaculture Lakes

Authors: Robby Y. Tallar, Nikodemus L., Yuri S., Jian P. Suen

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Research in the subject of ecological water resources management is full of trivial questions addressed and it seems, today to be one branch of science that can strongly contribute to the study of complexity (physical, biological, ecological, socio-economic, environmental, and other aspects). Existing literature available on different facets of these studies, much of it is technical and targeted for specific users. This study offered the combination all aspects in evaluation methodology for aquaculture lakes with its paradigm refer to hierarchical theory and to the effects of spatial specific arrangement of an object into a space or local area. Therefore, the process in developing a conceptual framework represents the more integrated and related applicable concept from the grounded theory. A design of integrated evaluation methodology for aquaculture lakes is presented. The method is based on the identification of a series of attributes which can be used to describe status of aquaculture lakes using certain indicators from aquaculture water quality index (AWQI), aesthetic aquaculture lake index (AALI) and rapid appraisal for fisheries index (RAPFISH). The preliminary preparation could be accomplished as follows: first, the characterization of study area was undertaken at different spatial scales. Second, an inventory data as a core resource such as city master plan, water quality reports from environmental agency, and related government regulations. Third, ground-checking survey should be completed to validate the on-site condition of study area. In order to design an integrated evaluation methodology for aquaculture lakes, finally we integrated and developed rating scores system which called Integrated Aquaculture Lake Index (IALI).The development of IALI are reflecting a compromise all aspects and it responds the needs of concise information about the current status of aquaculture lakes by the comprehensive approach. IALI was elaborated as a decision aid tool for stakeholders to evaluate the impact and contribution of anthropogenic activities on the aquaculture lake’s environment. The conclusion was while there is no denying the fact that the aquaculture lakes are under great threat from the pressure of the increasing human activities, one must realize that no evaluation methodology for aquaculture lakes can succeed by keeping the pristine condition. The IALI developed in this work can be used as an effective, low-cost evaluation methodology of aquaculture lakes for developing countries. Because IALI emphasizes the simplicity and understandability as it must communicate to decision makers and the experts. Moreover, stakeholders need to be helped to perceive their lakes so that sites can be accepted and valued by local people. For this site of lake development, accessibility and planning designation of the site is of decisive importance: the local people want to know whether the lake condition is safe or whether it can be used.

Keywords: aesthetic value, AHP, aquaculture lakes, integrated lakes, RAPFISH

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2874 Liquefaction Assessment of Marine Soil in Western Yemen Region Based on Laboratory and Field Tests

Authors: Monalisha Nayak, T. G. Sitharam

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Liquefaction is a major threat for sites consists of or on sandy soil. But this present study concentrates on the behavior of fine soil under cyclic loading. This paper presents the study of liquefaction susceptibility of marine silty clay to clayey silt for an offshore site near western Yemen. The submerged and loose sediment condition of marine soil of an offshore site can favour liquefaction during earthquakes. In this regard, the liquefaction susceptibility of the site was carried out based on both field test results and laboratory test results. From field test results of seismic cone penetration test (SCPT), liquefaction susceptibility was assessed considering normalized cone tip resistance, and normalized friction ratio and results give an idea regarding both cyclic mobility and flow liquefaction. Laboratory cyclic triaxial tests were also conducted on saturated undisturbed and remoulded sample to study the effect of cyclic loading on strength and strain characteristics. Liquefaction susceptibility of the marine soft soil was also carried out based on index properties like grain size distribution, natural moisture content and liquid limit of soil.

Keywords: index properties, liquefaction, marine soil, seismic cone penetration test (SCPT)

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2873 Specialised Financial Institutions and its Role in the Promotion of Small and Medium Enterprises in Kerala, India

Authors: K. V. Venugopalan

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Micro, Small and Medium Enterprises (MSMEs) have been accepted as the engine of economic growth and for promoting equitable development. The major advantage of the sector is its employment potential at low capital cost. The labour intensity of the MSME sector is much higher than that of the large enterprises. The MSMEs constitute over 90% of total enterprises in most of the economies and are credited with generating the highest rates of employment growth and account for a major share of industrial production and exports. Kerala is a small state in India with the limited land area with high potential in educated human resources need micro, small and medium enterprises for development. Kerala has the highest Physical Quality of Life Index (PQLI) in India and the highest Human Development Index (HDI) at par with the developed countries SME play an important role in alleviating poverty and contribute significantly towards the growth of developing economies. Financial institutions can play a vital role for the promotion of micro, small and medium enterprises in Kerala. The study entitled “Financial Institutions and its role in the promotion of Small and Medium Enterprises in Kerala “examine the progress of MSME in Kerala and India and also the role of financial institutions and the problems faced by entrepreneurs for getting advances with reference to ‘Kerala Financial Corporation’-an agency set up by the government for promoting small and medium enterprises in the state. This study is based on both secondary and primary data. Primary data for the study was collected from those entrepreneurs who availed advances from financial institutions. The secondary data include the investment made, goods and services provided, the employment generated and the number of units registered in MSME sector for the last 10 years in Kerala. The study concluded that financial institutions providing finance with simple procedures and charging smaller interest rates will increase the number of MSME's and also contribute gross state domestic product and reduce the unemployment problem and poverty in the economy.

Keywords: gross state domestic product, human development index, micro, small and medium enterprises

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2872 Risk and Reliability Based Probabilistic Structural Analysis of Railroad Subgrade Using Finite Element Analysis

Authors: Asif Arshid, Ying Huang, Denver Tolliver

Abstract:

Finite Element (FE) method coupled with ever-increasing computational powers has substantially advanced the reliability of deterministic three dimensional structural analyses of a structure with uniform material properties. However, railways trackbed is made up of diverse group of materials including steel, wood, rock and soil, while each material has its own varying levels of heterogeneity and imperfections. It is observed that the application of probabilistic methods for trackbed structural analysis while incorporating the material and geometric variabilities is deeply underworked. The authors developed and validated a 3-dimensional FE based numerical trackbed model and in this study, they investigated the influence of variability in Young modulus and thicknesses of granular layers (Ballast and Subgrade) on the reliability index (-index) of the subgrade layer. The influence of these factors is accounted for by changing their Coefficients of Variance (COV) while keeping their means constant. These variations are formulated using Gaussian Normal distribution. Two failure mechanisms in subgrade namely Progressive Shear Failure and Excessive Plastic Deformation are examined. Preliminary results of risk-based probabilistic analysis for Progressive Shear Failure revealed that the variations in Ballast depth are the most influential factor for vertical stress at the top of subgrade surface. Whereas, in case of Excessive Plastic Deformations in subgrade layer, the variations in its own depth and Young modulus proved to be most important while ballast properties remained almost indifferent. For both these failure moods, it is also observed that the reliability index for subgrade failure increases with the increase in COV of ballast depth and subgrade Young modulus. The findings of this work is of particular significance in studying the combined effect of construction imperfections and variations in ground conditions on the structural performance of railroad trackbed and evaluating the associated risk involved. In addition, it also provides an additional tool to supplement the deterministic analysis procedures and decision making for railroad maintenance.

Keywords: finite element analysis, numerical modeling, probabilistic methods, risk and reliability analysis, subgrade

Procedia PDF Downloads 136
2871 Enhanced Image Representation for Deep Belief Network Classification of Hyperspectral Images

Authors: Khitem Amiri, Mohamed Farah

Abstract:

Image classification is a challenging task and is gaining lots of interest since it helps us to understand the content of images. Recently Deep Learning (DL) based methods gave very interesting results on several benchmarks. For Hyperspectral images (HSI), the application of DL techniques is still challenging due to the scarcity of labeled data and to the curse of dimensionality. Among other approaches, Deep Belief Network (DBN) based approaches gave a fair classification accuracy. In this paper, we address the problem of the curse of dimensionality by reducing the number of bands and replacing the HSI channels by the channels representing radiometric indices. Therefore, instead of using all the HSI bands, we compute the radiometric indices such as NDVI (Normalized Difference Vegetation Index), NDWI (Normalized Difference Water Index), etc, and we use the combination of these indices as input for the Deep Belief Network (DBN) based classification model. Thus, we keep almost all the pertinent spectral information while reducing considerably the size of the image. In order to test our image representation, we applied our method on several HSI datasets including the Indian pines dataset, Jasper Ridge data and it gave comparable results to the state of the art methods while reducing considerably the time of training and testing.

Keywords: hyperspectral images, deep belief network, radiometric indices, image classification

Procedia PDF Downloads 274
2870 Identification and Optimisation of South Africa's Basic Access Road Network

Authors: Diogo Prosdocimi, Don Ross, Matthew Townshend

Abstract:

Road authorities are mandated within limited budgets to both deliver improved access to basic services and facilitate economic growth. This responsibility is further complicated if maintenance backlogs and funding shortfalls exist, as evident in many countries including South Africa. These conditions require authorities to make difficult prioritisation decisions, with the effect that Road Asset Management Systems with a one-dimensional focus on traffic volumes may overlook the maintenance of low-volume roads that provide isolated communities with vital access to basic services. Given these challenges, this paper overlays the full South African road network with geo-referenced information for population, primary and secondary schools, and healthcare facilities to identify the network of connective roads between communities and basic service centres. This connective network is then rationalised according to the Gross Value Added and number of jobs per mesozone, administrative and functional road classifications, speed limit, and road length, location, and name to estimate the Basic Access Road Network. A two-step floating catchment area (2SFCA) method, capturing a weighted assessment of drive-time to service centres and the ratio of people within a catchment area to teachers and healthcare workers, is subsequently applied to generate a Multivariate Road Index. This Index is used to assign higher maintenance priority to roads within the Basic Access Road Network that provide more people with better access to services. The relatively limited incidence of Basic Access Roads indicates that authorities could maintain the entire estimated network without exhausting the available road budget before practical economic considerations get any purchase. Despite this fact, a final case study modelling exercise is performed for the Namakwa District Municipality to demonstrate the extent to which optimal relocation of schools and healthcare facilities could minimise the Basic Access Road Network and thereby release budget for investment in roads that best promote GDP growth.

Keywords: basic access roads, multivariate road index, road prioritisation, two-step floating catchment area method

Procedia PDF Downloads 224
2869 Income Diversification of Small Holder Farmers in Bosso Local Government Area of Niger State, Nigeria

Authors: Oladipo Joseph Ajayi, Yakubu Muhammed, Caleb Galadima

Abstract:

This study was conducted to examine the income diversification of smallholder farmers in Bosso Local Government area of Niger state, Nigeria. The specific objectives were to examine the socio-economic characteristics of the farmers, identify the sources of income among the farmers, determine the pattern of income diversification and evaluate the determinants of income diversification of farmers in the study area. A multi-stage sampling technique was used to select 94 respondents for the study. Primary data were used, and these were collected with aid of a well structured interview schedule. Descriptive statistics, diversity index, and Tobit regression model were employed to analyze the data. The mean age of the farmers was 44 years. The average household size was 8 members per household, and the average farming experience was 12 years. 21.27 percent did not have formal education. It was further found that 69.1 percent of the respondents had an income diversity index of 0.3-0.4. This indicated that their level of income diversification was moderately low. The determinants of income diversification in the study area were education, household size, marital status, and primary income. These variables were positively related to income diversification. The study revealed that diversification into various income sources has helped to increase household income to sustain the family demands even though their level of income diversification was low within the study area.

Keywords: diversification, income, households, smallholder farmers

Procedia PDF Downloads 243
2868 Prevalence of Obesity and Associated Risk Factors in South African Employees

Authors: Jeanne Grace, Shereen Currie

Abstract:

Background: Obesity associated comorbidities increase the risk of morbidity and mortality among employees in the workplace. Objectives: The study aimed to determine the prevalence of obesity and comorbidities like diabetes, hypertension, and hypercholesterolemia associated with obesity within the workplace in South Africa. Methods: A total of 17359 male (n = 8561) and female (n = 8798) employees, aged between 18-64 years (40.8 ± 11.0), from various corporate and industrial companies in South Africa participated in the study. Subjects were assigned to one of five body mass index (BMI) categories, according to their BMI: normal weight, BMI of 18.5‒24.9 kg/m² (n = 7338); overweight, BMI of 25.0‒29.9 kg/m² (n = 6323); obese class I, BMI of 30.0-34.9 kg/m² (n = 2552); obese class II, BMI of 35.0-39.9 kg/m² (n = 782); and obese class III, BMI of ≥ 40 kg/m² (n = 364). Height, weight, blood pressure, random blood glucose, and total cholesterol were measured. Results: The prevalence of normal weight men was 29.2% and women 55.0%; overweight men 46.4% and women 26.7%, obese men 24.4% and women 18.3%. A significant association (p<0.01) of BMI with diabetes, systolic and diastolic hypertension, and hypercholesterolemia were noted. Conclusion: Obesity is strongly associated with adverse comorbidities that may impact employees’ quality of life and performance. If unaddressed, it can increase comorbidities, not only affecting the bottom line of companies but causing morbidity and mortality, including sudden death.

Keywords: body mass index, cholesterol, blood glucose, workplace

Procedia PDF Downloads 179
2867 The Association of Anthropometric Measurements, Blood Pressure Measurements, and Lipid Profiles with Mental Health Symptoms in University Students

Authors: Ammaarah Gamieldien

Abstract:

Depression is a very common and serious mental illness that has a significant impact on both the social and economic aspects of sufferers worldwide. This study aimed to investigate the association between body mass index (BMI), blood pressure, and lipid profiles with mental health symptoms in university students. Secondary objectives included the associations between the variables (BMI, blood pressure, and lipids) with themselves, as they are key factors in cardiometabolic disease. Sixty-three (63) students participated in the study. Thirty-two (32) were assigned to the control group (minimal-mild depressive symptoms), while 31 were assigned to the depressive group (moderate to severe depressive symptoms). Montgomery-Asberg Depression Rating Scale (MADRS) and Beck Depression Inventory (BDI) were used to assess depressive scores. Anthropometric measurements such as weight (kg), height (m), waist circumference (WC), and hip circumference were measured. Body mass index (BMI) and ratios such as waist-to-hip ratio (WHR) and waist-to-height ratio (WtHR) were also calculated. Blood pressure was measured using an automated AfriMedics blood pressure machine, while lipids were measured using a CardioChek plus analyzer machine. Statistics were analyzed via the SPSS statistics program. There were no significant associations between anthropometric measurements and depressive scores (p > 0.05). There were no significant correlations between lipid profiles and depression when running a Spearman’s rho correlation (P > 0.05). However, total cholesterol and LDL-C were negatively associated with depression, and triglycerides were positively associated with depression after running a point-biserial correlation (P < 0.05). Overall, there were no significant associations between blood pressure measurements and depression (P > 0.05). However, there was a significant moderate positive correlation between systolic blood pressure and MADRS scores in males (P < 0.05). Depressive scores positively and strongly correlated to how long it takes participants to fall asleep. There were also significant associations with regard to the secondary objectives. This study indicates the importance of determining the prevalence of depression among university students in South Africa. If the prevalence and factors associated with depression are addressed, depressive symptoms in university students may be improved.

Keywords: depression, blood pressure, body mass index, lipid profiles, mental health symptoms

Procedia PDF Downloads 59
2866 Criticality Assessment Model for Water Pipelines Using Fuzzy Analytical Network Process

Authors: A. Assad, T. Zayed

Abstract:

Water networks (WNs) are responsible of providing adequate amounts of safe, high quality, water to the public. As other critical infrastructure systems, WNs are subjected to deterioration which increases the number of breaks and leaks and lower water quality. In Canada, 35% of water assets require critical attention and there is a significant gap between the needed and the implemented investments. Thus, the need for efficient rehabilitation programs is becoming more urgent given the paradigm of aging infrastructure and tight budget. The first step towards developing such programs is to formulate a Performance Index that reflects the current condition of water assets along with its criticality. While numerous studies in the literature have focused on various aspects of condition assessment and reliability, limited efforts have investigated the criticality of such components. Critical water mains are those whose failure cause significant economic, environmental or social impacts on a community. Inclusion of criticality in computing the performance index will serve as a prioritizing tool for the optimum allocating of the available resources and budget. In this study, several social, economic, and environmental factors that dictate the criticality of a water pipelines have been elicited from analyzing the literature. Expert opinions were sought to provide pairwise comparisons of the importance of such factors. Subsequently, Fuzzy Logic along with Analytical Network Process (ANP) was utilized to calculate the weights of several criteria factors. Multi Attribute Utility Theories (MAUT) was then employed to integrate the aforementioned weights with the attribute values of several pipelines in Montreal WN. The result is a criticality index, 0-1, that quantifies the severity of the consequence of failure of each pipeline. A novel contribution of this approach is that it accounts for both the interdependency between criteria factors as well as the inherited uncertainties in calculating the criticality. The practical value of the current study is represented by the automated tool, Excel-MATLAB, which can be used by the utility managers and decision makers in planning for future maintenance and rehabilitation activities where high-level efficiency in use of materials and time resources is required.

Keywords: water networks, criticality assessment, asset management, fuzzy analytical network process

Procedia PDF Downloads 142
2865 Salinity Response of Some Chickpea (Cicer arietinum L.) Genotypes in Germination and Seedling Growth of Periods

Authors: Onder Aldemir, Ercan Ceyhan

Abstract:

The research was conducted to determine effects of salt concentrations on emergence and seedling development of chickpea genotypes. Trials were performed during the year of 2013 on the laboratory and greenhouse of Agricultural Faculty, Selcuk University. Emergency trial was set up according to ‘Randomized Plots Design’ by two factors and four replications; greenhouse trial was also set up according to ‘Randomized Plots Design’ by two factors with three replications. The chickpea genotypes; CA119, CA132, CA149, CA150, CA215, CA222, CA235, CA261, Bozkır and Gokce were used as material for both of the trials. Effects of the five doses of salt concentrations (control, 30 mM, 60 mM, 90 mM and 120 mM) on the ratio of emergency, speed of emergency, average time for emergency, index of sensibility, length of shoot and root, fresh weight of shoot and root, dry weight of shoot and root, index of salt tolerance were evaluated. Responses of the chickpea genotypes for salt concentrations were found different. Comparing to the control, all of the investigated characteristics on the chickpea genotypes showed significant reduction by depending on the increasing salt level. According to the effects of salt application, the chickpea genotypes Gokce, CA215 and CA222 were the most tolerant in respect to plant dry weights while the chickpea genotypes CA149 and CA150 were the most sensitive.

Keywords: chickpea, emergence, salt tolerant, seedling development

Procedia PDF Downloads 224
2864 Strategy Management of Soybean (Glycine max L.) for Dealing with Extreme Climate through the Use of Cropsyst Model

Authors: Aminah Muchdar, Nuraeni, Eddy

Abstract:

The aims of the research are: (1) to verify the cropsyst plant model of experimental data in the field of soybean plants and (2) to predict planting time and potential yield soybean plant with the use of cropsyst model. This research is divided into several stages: (1) first calibration stage which conducted in the field from June until September 2015.(2) application models stage, where the data obtained from calibration in the field will be included in cropsyst models. The required data models are climate data, ground data/soil data,also crop genetic data. The relationship between the obtained result in field with simulation cropsyst model indicated by Efficiency Index (EF) which the value is 0,939.That is showing that cropsyst model is well used. From the calculation result RRMSE which the value is 1,922%.That is showing that comparative fault prediction results from simulation with result obtained in the field is 1,92%. The conclusion has obtained that the prediction of soybean planting time cropsyst based models that have been made valid for use. and the appropriate planting time for planting soybeans mainly on rain-fed land is at the end of the rainy season, in which the above study first planting time (June 2, 2015) which gives the highest production, because at that time there was still some rain. Tanggamus varieties more resistant to slow planting time cause the percentage decrease in the yield of each decade is lower than the average of all varieties.

Keywords: soybean, Cropsyst, calibration, efficiency Index, RRMSE

Procedia PDF Downloads 174
2863 Antioxidant Effects of Regular Aerobic Exercise in Postmenopausal Women with Type 2 Diabetes Mellitus

Authors: Parvin Farzanegi

Abstract:

Background: Diabetes is a metabolic disorder associated with increased free radicals and oxidative stress. The evidence indicates that physical inactivity is a modifiable behavioral risk factor for a wide range of chronic disorders such as diabetes mellitus. We investigated the effects of eight-week aerobic exercise on some antioxidant enzyme activities in postmenopausal women with type 2 diabetes mellitus (T2DM). Methods: sixteen sedentary postmenopausal women with T2DM were randomly assigned to the control (n=8; CG) and exercise group (n=8; EG). The exercise consisted of progressive aerobic training at a moderate intensity (50-70% of the maximum heart rate), for 25-60 min/day, and 3 days/week for 8 weeks. Age, sex, and body mass index were similar in the two groups. Antioxidant status was evaluated by measuring the superoxide dismutase (SOD) and catalase (CAT) activity. Also levels of malondialdehyde (MDA) as an index of lipid peroxidation and glucose in the plasma were measured before and after the intervention. Results: Following the 8 weeks of exercise training, the plasma MDA and glucose levels were significantly reduced in EG compared to CG (P=0.001 and P=0.011 respectively). However, SOD (P=0.017) and CAT (P=0.011) activities were increased in EG compared to CG. Conclusion: The present study suggests regular aerobic exercise appears can exert protective effects against oxidative stress due to its ability to increase antioxidant defense and glucose control in postmenopausal women with T2DM.

Keywords: aerobic exercise, antioxidant, diabetes mellitus, type 2

Procedia PDF Downloads 166
2862 Predicting OpenStreetMap Coverage by Means of Remote Sensing: The Case of Haiti

Authors: Ran Goldblatt, Nicholas Jones, Jennifer Mannix, Brad Bottoms

Abstract:

Accurate, complete, and up-to-date geospatial information is the foundation of successful disaster management. When the 2010 Haiti Earthquake struck, accurate and timely information on the distribution of critical infrastructure was essential for the disaster response community for effective search and rescue operations. Existing geospatial datasets such as Google Maps did not have comprehensive coverage of these features. In the days following the earthquake, many organizations released high-resolution satellite imagery, catalyzing a worldwide effort to map Haiti and support the recovery operations. Of these organizations, OpenStreetMap (OSM), a collaborative project to create a free editable map of the world, used the imagery to support volunteers to digitize roads, buildings, and other features, creating the most detailed map of Haiti in existence in just a few weeks. However, large portions of the island are still not fully covered by OSM. There is an increasing need for a tool to automatically identify which areas in Haiti, as well as in other countries vulnerable to disasters, that are not fully mapped. The objective of this project is to leverage different types of remote sensing measurements, together with machine learning approaches, in order to identify geographical areas where OSM coverage of building footprints is incomplete. Several remote sensing measures and derived products were assessed as potential predictors of OSM building footprints coverage, including: intensity of light emitted at night (based on VIIRS measurements), spectral indices derived from Sentinel-2 satellite (normalized difference vegetation index (NDVI), normalized difference built-up index (NDBI), soil-adjusted vegetation index (SAVI), urban index (UI)), surface texture (based on Sentinel-1 SAR measurements)), elevation and slope. Additional remote sensing derived products, such as Hansen Global Forest Change, DLR`s Global Urban Footprint (GUF), and World Settlement Footprint (WSF), were also evaluated as predictors, as well as OSM street and road network (including junctions). Using a supervised classification with a random forest classifier resulted in the prediction of 89% of the variation of OSM building footprint area in a given cell. These predictions allowed for the identification of cells that are predicted to be covered but are actually not mapped yet. With these results, this methodology could be adapted to any location to assist with preparing for future disastrous events and assure that essential geospatial information is available to support the response and recovery efforts during and following major disasters.

Keywords: disaster management, Haiti, machine learning, OpenStreetMap, remote sensing

Procedia PDF Downloads 115
2861 Investigating Convective Boiling Heat Transfer Characteristics of R-1234ze and R-134a Refrigerants in a Microfin and Smooth Tube

Authors: Kaggwa Abdul, Chi-Chuan Wang

Abstract:

This research is based on R-1234ze that is considered to substitute R-134a due to its low global warming potential in a microfin tube with outer diameter 9.52 mm, number of fins 70, and fin height 0.17 mm. In comparison, a smooth tube with similar geometries was used to study pressure drop and heat transfer coefficients related to the two fluids. The microfin tube was brazed inside a stainless steel tube and heated electrically. T-type thermocouples used to measure the temperature distribution during the phase change process. The experimental saturation temperatures and refrigerant mass velocities varied from 10 – 20°C and 50 – 300 kg/m2s respectively. The vapor quality from 0.1 to 0.9, and heat flux ranged from 5 – 11kW/m2. The results showed that heat transfer performance of R-134a in both microfin and smooth tube was better than R-1234ze especially at mass velocities above G = 50 kg/m2s. However, at low mass velocities below G = 100 kg/m2s R-1234ze yield better heat transfer coefficients than R-134a. The pressure gradient of R-1234ze was markedly higher than that of R-134a at all mass flow rates.

Keywords: R-1234ze and R-134a, horizontal flow boiling, pressure drop, heat transfer coefficients, micro-fin and smooth tubes

Procedia PDF Downloads 278
2860 Wetting-Drying Cycles Effect on Piles Embedded in a Very High Expansive Soil

Authors: Bushra Suhail, Laith Kadim

Abstract:

The behavior of model piles embedded in a very high expansive soil was investigated, a specially manufactured saturation-drying tank was used to apply three cycles of wetting and drying to the expansive soil surrounding the model straight shaft and under reamed piles, the relative movement of the piles with respect to the soil surface was recorded with time, also the exerted uplift pressure of the piles due to soil swelling was recorded. The behavior of unloaded straight shaft and under reamed piles was investigated. Two design charts were presented for straight shaft and under reamed piles one for the required pile depth for zero upward movement due to soil swelling, the other for the required pile depth to exert zero uplift pressure when the soil swells. Under reamed piles showed a decrease in upward movement of 20% to 40%, and an uplift pressure decrease of 10% to 30%.

Keywords: expansive soil, piles, under reamed, structural and geotechnical engineering

Procedia PDF Downloads 312