Search results for: heat index (HI)

Authors: Jerickson Abbie Flores, Jana Fragante, Jan Paolo Dipasupil, Jan Jorge Francisco

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Malnutrition is one of the rapidly growing health problems affecting the world at present. Children affected are not only at risk for significant health problems, but are also faced with psychological and social consequences, including low self-esteem. School-age children are specifically vulnerable to develop poor self-esteem especially when their peers find them physically unattractive. Thus, malnutrition, whether obesity or undernourishment, contributes a significant role to a developing child’s health and behavior. This research aims to determine if there is a significant difference on the level of self-esteem among Filipino children ages 9-12 years old with abnormal body mass index (BMI) and those children with desirable BMI. Using a cross-sectional study design, the correlation between body mass index (BMI) and self-esteem was observed among children ages 9-12 years old. Participants took the Hare self esteem questionnaire, which is specifically designed to measure self-esteem in school age children. The lowest possible score is 15 and the highest possible score is 45. A total of 1140 students with ages 9-12 years old from Cembo Elementary School (public school) participated in the study. Among the participants, 239 out of the 1140 have desirable body mass index, 878 are underweight, and 23 are overweight. Using the test questionnaire, the computed mean scores were 36.599, 36.045 and 36.583 for normal, underweight and overweight categories respectively. Using Pearson’s Correlation Test and Spearman’s Correlation Coefficient Test, the study showed positive correlation (p value of 0.047 and 0.004 respectively) between BMI and Self-esteem scores which indicates that the higher the BMI, the higher the self-esteem of the participants.

Keywords: body mass index, malnutrition, school-age children, self-esteem

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Authors: Surekha Rathod

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Sickle cell disease is a vascular disorder characterized by chronic, ongoing organ damage that is punctuated by episodes of acutely painful vascular complications.1 It is the most common genetic blood disorder in the United States, with about 2000 infants being identified through routine blood screenings annually, and an estimated 104,000-138,000 affected individuals living in the United States. Approximately 0.3%-1.3% of African American are affected by Sickle Cell Diseases (SCD).3 The aim of this paper is to present oral health status of patients with SCD. A total of 200 subjects of both sexes in the age group 18- 40 years were included in this study. The subjects were examined and the following indices were recorded • Oral hygiene index – Simplified (OHI-S). • Probing depths (PD). • Clinical Attachment Levels (CAL). • Gingival Index - Loe and Sillness. • Turesky Gillmore Glickman Modification of the Quigley Hein Plaque Index. (1970) • DMFT index. • Sickle Cell Disease Severity Index. A total of 1478 patients were screened of which 200 subjects were found to be diagnosed with SCD by electrophoresis. The study thus, included 200 subjects (111 females & 89 males) diagnosed with Sickle Cell Disease in the age group of 18-40 years. The probing pocket depths (PPD) were measured in millimeters. 36% had PPD in the range of 2-4mm, 48% had PPD in the range of 4-6mm while 16% had PPD of more than 6mm. Similar results were obtained for the Clinical Attachment Levels (CAL). 29.5 % subjects had CAL 2-4mm, 44.5% had 4-6mm & 26% had CAL 6mm & above. We can thus conclude that although oral health is not a priority for patients with SCD, it is supported by increased plaque accumulation. Because of the chronic anemic state of the patients with SCD, they should be encouraged to pay strict attention to oral hygiene instructions and practice.

Keywords: chronic, genetic, oral, sickle cell disease, vascular

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Authors: Liudmila Garzanova, Lidia Ananyeva, Olga Koneva, Olga Ovsyannikova, Oxana Desinova, Mayya Starovoytova, Rushana Shayahmetova, Anna Khelkovskaya-Sergeeva

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Objectives. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are associated with severe course, increased morbidity and mortality in systemic sclerosis (SSc). The aim of our study was to assess changes in CRP and ESR in SSc patients during long-term RTX therapy. Methods. This study included 113 patients with SSc. Mean age was 48.1±13 years, female-85%. The mean disease duration was 6±5 years. The diffuse cutaneous subset of the disease had 55% of patients. All pts had interstitial lung disease (ILD). All patients received prednisolone at a mean dose of 11.6±4.8 mg/day, and 53 of them - were immunosuppressants at inclusion. Patients received RTX due to the ineffectiveness of previous therapy for ILD. The parameters were evaluated over the periods: at baseline (point 0), 13±2.3 month (point 1, n=113), 42±14 month (point 2, n=80) and 79±6.5 month (point 3, n=25) after initiation of RTX therapy. Cumulative mean dose of RTX at point 1 = 1.7±0.6g, at point 2 = 3±1.5g, and at point 3 = 3.8±2.4g. The results are presented in the form of mean values, delta(Δ)-difference between the baseline parameter and follow-up point. Results. There was an improvement in studied parameters on RTX therapy. There was a significant decrease of ESR, CRP and activity index (EScSG-AI) at all observation points (p=0.001). In point 1: ΔCRP was 6.7 mg/l, ΔESR = 7.4 mm/h, ΔActivity index (EScSG-AI) = 1.7. In point 2: ΔCRP was 8.7 mg/l, ΔESR = 7.5 mm/h, ΔActivity index (EScSG-AI) = 1.9. In point 3: ΔCRP was 16.1 mg/l, ΔESR = 11 mm/h, ΔActivity index (EScSG-AI) = 2.1. Conclusion. There was a significant decrease in CRP and ESR during long-term RTX therapy, which correlated with a decrease in the disease activity index. RTX is an effective treatment option for SSc with an elevation of acute-phase reactants.

Keywords: C-reactive protein, interstitial lung disease, systemic sclerosis, rituximab

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Authors: Carlos A. Acosta, Amar Bhalla, Ruyan Guo

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Scraped surface heat exchangers (SSHE) use a rotor shaft assembly with scraping blades to homogenize viscous fluids during the heat transfer process. Obtaining in-situ measurements is difficult because the rotor and scraping blades spin continuously inside the mixing chamber, obstructing the instrumentation pathway. Computational fluid dynamics simulations provide useful insight into the flow behavior around the scraper blades for a variety of fluids and blade geometries. However, numerical solutions often focus on the fluid dynamics and heat transfer phenomena of rotating flow, ignoring the glass-transition temperature and freezing point depression. This research studies the multi-phase fluid dynamics and freezing point depression inside the SSHE with non-isothermal conditions in a time dependent process using an aqueous solution that contains 13.5 wt.% high fructose corn syrup and CO₂. The computational results were validated with in-situ pressure, temperature, and optical spectroscopy measurements. Results from the numerical model show good quantitatively agreement with experimental values.

Keywords: computational fluid dynamics, freezing point depression, phase-transition temperature, multi-phase flow

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Authors: Metwally Abdel Aziz Ahmed, Ahmed Shaban Abdel Hay Gabr, Inas Mohamed Saleh

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The main objective of structural design is to ensure safety and functional performance requirements of a structural system for its target reliability levels. In this study, the reliability index for the reinforcement concrete slender columns with rectangular cross section is studied. The variable parameters studied include the loads, the concrete compressive strength, the steel yield strength, the dimensions of concrete cross-section, the reinforcement ratio, and the location of steel placement. Risk analysis program was used to perform the analytical study. The effect of load eccentricity on the reliability index of reinforced concrete slender column was studied and presented. The results of this study indicate that the good quality control improve the performance of slender reinforced columns through increasing the reliability index β.

Keywords: reliability, reinforced concrete, safety, slender column

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Authors: Mustafa Col, Funda Gul Koc, Merve Yangaz, Eylem Subasi, Can Akbasoglu

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G38NiCrMo8-4-4 steel is widely used in mining industries, machine parts, gears due to its high strength and toughness properties. In this study, microstructure, wear and mechanical properties of G38NiCrMo8-4-4 steel modified with boron used in the mining industry were investigated. For this purpose, cast materials were alloyed by melting in an induction furnace to include boron with the rates of 0 ppm, 15 ppm, and 50 ppm (wt.) and were formed in the dimensions of 150x200x150 mm by casting into the sand mould. Homogenization heat treatment was applied to the specimens at 1150˚C for 7 hours. Then all specimens were austenitized at 930˚C for 1 hour, quenched in the polymer solution and tempered at 650˚C for 1 hour. Microstructures of the specimens were investigated by using light microscope and SEM to determine the effect of boron and heat treatment conditions. Changes in microstructure properties and material hardness were obtained due to increasing boron content and heat treatment conditions after microstructure investigations and hardness tests. Wear tests were carried out using a pin-on-disc tribometer under dry sliding conditions. Charpy V notch impact test was performed to determine the toughness properties of the specimens. Fracture and worn surfaces were investigated with scanning electron microscope (SEM). The results show that boron element has a positive effect on the hardness and wear properties of G38NiCrMo8-4-4 steel.

Keywords: G38NiCrMo8-4-4 steel, boron, heat treatment, microstructure, wear, mechanical properties

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Authors: H. F. Hozyen, A. M. Abo-El Maaty

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Heat stress is a recognized problem causing huge economic losses to the buffalo breeders as well as dairy industry. The aim of the present work was to study the pattern of vitamin C and nitric oxide in follicular fluid of buffalo during different seasons of the year considering phase of estrous cycle. This study was conducted on 208 cyclic buffaloes slaughtered at Al-Qaliobia governorate, Egypt, over one year. The obtained results revealed that vitamin C in follicular fluid was significantly lower in summer than winter and spring. On the other hand, nitric oxide (NO) was significantly higher in summer and autumn than winter and spring. Both vitamin C and NO did not differ significantly between follicular and luteal phases. In conclusion, the present study revealed that alterations in concentrations of follicular fluid vitamin C and NO that occur in summer could be related to low summer fertility in buffalo.

Keywords: Buffalo, follicular fluid, vitamin C, nitric oxide, heat stress

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Authors: Z. Hormozi Moghaddam, M. Mokhtari-Dizaji, M. Movahedin, M. E. Ravari

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Mechanical index (MI) is used for quantifying acoustic cavitation and the relationship between acoustic pressure and the frequency. In this study, modeling of the MI was applied to provide treatment protocol and to understand the effective physical processes on reproducibility of stem cells. The acoustic pressure and MI equations are modeled and solved to estimate optimal MI for 28, 40, 150 kHz and 1 MHz frequencies. Radial and axial acoustic pressure distribution was extracted. To validate the results of the modeling, the acoustic pressure in the water and near field depth was measured by a piston hydrophone. Results of modeling and experiments show that the model is consistent well to experimental results with 0.91 and 0.90 correlation of coefficient (p<0.05) for 1 MHz and 40 kHz. Low intensity ultrasound with 0.40 MI is more effective on the proliferation rate of the spermatogonial stem cells during the seven days of culture, in contrast, high MI has a harmful effect on the spermatogonial stem cells. This model provides proper treatment planning in vitro and in vivo by estimating the cavitation phenomenon.

Keywords: ultrasound, mechanical index, modeling, stem cell

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Authors: Rekha S., S. J. Nalini, S. Bhuvana, S. Kanmani, Vidhya Venugopal

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Introduction: Pregnant women's occupational heat exposure has been linked to foetal abnormalities and pregnancy complications. The presence of heat in the workplace is expected to lead to Adverse Pregnancy Outcomes (APO), especially in tropical countries where temperatures are rising and workplace cooling interventions are minimal. For effective interventions, in-depth understanding and evidence about occupational heat stress and APO are required. Methodology: Approximately 800 pregnant women in and around Chennai who were employed in jobs requiring moderate to hard labour participated in the cohort research. During the study period (2014-2019), environmental heat exposures were measured using a Questemp WBGT monitor, and heat strain markers, such as Core Body Temperature (CBT) and Urine Specific Gravity (USG), were evaluated using an Infrared Thermometer and a refractometer, respectively. Using a valid HOTHAPS questionnaire, self-reported health symptoms were collected. In addition, a postpartum follow-up with the mothers was done to collect APO-related data. Major findings of the study: Approximately 47.3% of pregnant workers have workplace WBGTs over the safe manual work threshold value for moderate/heavy employment (Average WBGT of 26.6°C±1.0°C). About 12.5% of the workers had CBT levels above the usual range, and 24.8% had USG levels above 1.020, both of which suggested mild dehydration. Miscarriages (3%), stillbirths/preterm births (3.5%), and low birth weights (8.8%) were the most common unfavorable outcomes among pregnant employees. In addition, WBGT exposures above TLVs during all trimesters were associated with a 2.3-fold increased risk of adverse fetal/maternal outcomes (95% CI: 1.4-3.8), after adjusting for potential confounding variables including age, education, socioeconomic status, abortion history, stillbirth, preterm, LBW, and BMI. The study determined that WBGTs in the workplace had direct short- and long-term effects on the health of both the mother and the foetus. Despite the study's limited scope, the findings provided valuable insights and highlighted the need for future comprehensive cohort studies and extensive data in order to establish effective policies to protect vulnerable pregnant women from the dangers of heat stress and to promote reproductive health.

Keywords: adverse outcome, heat stress, interventions, physiological strain, pregnant women

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Authors: J. R. Lee, E. V. Lau

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Ionic wind is developed when high voltage is supplied to an anode and a grounded cathode in a gaseous medium. This paper studies the ionic wind profile with different anode configurations, the relationship between electrode gap against the voltage supplied and finally a comparison of the heat transfer coefficient of ionic wind over a horizontal flat plate against a conventional fan experimentally. It is observed that increase in the distance between electrodes decreases at a rate of 1-e-0.0206x as the voltage supply is increased until a distance of 3.1536cm. It is also observed that the wind speed produced by ionic wind is stronger, 2.7ms-1 at 2W compared to conventional fan, 2.5ms-1 at 2W but the wind produced decays at a fast exponential rate and is more localized as compared to conventional fan wind that decays at a slower exponential rate and is less localized. Next, it is found out that the ionic wind profile is the same regardless of the position of the anode relative to the cathode. Lastly, it is discovered that ionic wind produced a heat transfer coefficient that is almost 1.6 times higher compared to a conventional fan with Nusselt number reaching 164 compared to 102 for conventional fan.

Keywords: conventional fan, heat transfer, ionic wind, wind profile

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Authors: E. Vlachopapadopoulou, E. Dikaiakou, E. Anagnostou, I. Panagiotopoulos, E. Kaloumenou, M. Kafetzi, A. Fotinou, S. Michalacos

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Aim: To investigate the relation and impact of Body Mass Index (BMI), Waist Circumference (WC) and Body Fat Weight (BFW) on insulin resistance (MATSUDA INDEX < 2.5) in children and adolescents. Methods: Data from 95 overweight and obese children (47 boys and 48 girls) with mean age 10.7 ± 2.2 years were analyzed. ROC analysis was used to investigate the predictive ability of BMI, WC and BFW for insulin resistance and find the optimal cut-offs. The overall performance of the ROC analysis was quantified by computing area under the curve (AUC). Results: ROC curve analysis indicated that the optimal-cut off of WC for the prediction of insulin resistance was 97 cm with sensitivity equal to 75% and specificity equal to 73.1%. AUC was 0.78 (95% CI: 0.63-0.92, p=0.001). The sensitivity and specificity of obesity for the discrimination of participants with insulin resistance from those without insulin resistance were equal to 58.3% and 75%, respectively (AUC=0.67). BFW had a borderline predictive ability for insulin resistance (AUC=0.58, 95% CI: 0.43-0.74, p=0.101). The predictive ability of WC was equivalent with the correspondence predictive ability of BMI (p=0.891). Obese subjects had 4.2 times greater odds for having insulin resistance (95% CI: 1.71-10.30, p < 0.001), while subjects with WC more than 97 had 8.1 times greater odds for having insulin resistance (95% CI: 2.14-30.86, p=0.002). Conclusion: BMI and WC are important clinical factors that have significant clinical relation with insulin resistance in children and adolescents. The cut off of 97 cm for WC can identify children with greater likelihood for insulin resistance.

Keywords: body fat weight, body mass index, insulin resistance, obese children, waist circumference

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Authors: Indrajit Ghosh, Jaydip Roy

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Literacy rate is an important indicator for measurement of human development. But this is not a good one to capture the qualitative dimension of educational attainment of an individual or a society. The overall educational level of an area is an important issue beyond the literacy rate. The overall educational level can be thought of as an outcome of the educational levels of individuals. But there is no well-defined algorithm and mathematical model available to measure the overall educational level of an area. A heuristic approach based on accumulated experience of experts is effective one. It is evident that fuzzy logic offers a natural and convenient framework in modeling various concepts in social science domain. This work suggests the implementation of fuzzy logic to develop a mathematical model for measurement of educational attainment of an area in terms of Education Index. The contribution of the study is two folds: conceptualization of “Education Profile” and proposing a new mathematical model to measure educational attainment in terms of “Education Index”.

Keywords: education index, education profile, fuzzy logic, literacy

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Authors: Ji-Suk Kim, Dong-Pil Kim, Kee-Rae Gang, Yoon Ho Choi

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This study was conducted to investigate the characteristics of butterfly communities according to the habitat characteristics of Korean veins. The survey sites were 12 mountains located in the vein, and 12~30 quadrats (200 in total) were set. The species richness and biodiversity were different according to land use type. Two types of land use (forest and graveyard) showed lower species diversity index values ​​than other land use types. The species abundance was low in the forest and graveyards, and grasslands, forest tops, cultivated areas and urban areas showed relatively high species richness. The altitude was not statistically significant with the number of species of butterflies and biodiversity index. The degree of canopy closure showed a negative correlation. As a result of interspecific correlation analysis, it was confirmed that there was a very high correlation (R2=0.746) between Lycaena phlaeas and Pseudozizeeria maha argia, Choaspes benjaminii japonica and Argyronome ruslana.

Keywords: land use type, species diversity index, correlation, canopy closure

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Authors: Nicolas Thiers, Romain Gers, Olivier Skurtys

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In this work, we study numerically the effect of a thermal perturbation on the heat transfer in a rectangular differentially heated cavity of aspect ratio 4, filled by air. In order to maintain the center symmetry, the thermal perturbation is imposed by a square wave at both active walls, at the same relative position of the hot or cold boundary layers. The influences of the amplitude and the vertical location of the perturbation are investigated. The air flow is calculated solving the unsteady Boussinesq-Navier-Stokes equations using the PN - PN-2 Spectral Element Method (SEM) programmed in the Nek5000 opencode, at RaH= 9x107, just before the first bifurcation which leads to periodical flow. The results show that the perturbation has a major impact for the highest amplitude, and at about three quarters of the cavity height, upstream, in both hot and cold boundary layers.

Keywords: direct numerical simulation, heat transfer enhancement, localized thermal perturbations, natural convection, rectangular differentially-heated cavity

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Authors: B. Dehghan, T. Toppi, M. Aprile, M. Motta

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The environmental concerns related to global warming and ozone layer depletion along with the growing worldwide demand for heating and cooling have brought an increasing attention toward ecological and efficient Heating, Ventilation, and Air Conditioning (HVAC) systems. Furthermore, since space heating accounts for a considerable part of the European primary/final energy use, it has been identified as one of the sectors with the most challenging targets in energy use reduction. Heat pumps are commonly considered as a technology able to contribute to the achievement of the targets. Current research focuses on the full load operation and seasonal performance assessment of three gas-driven absorption heat pump cycles. To do this, investigations of the gas-driven air-source ammonia-water absorption heat pump systems for small-scale space heating applications are presented. For each of the presented cycles, both full-load under various temperature conditions and seasonal performances are predicted by means of numerical simulations. It has been considered that small capacity appliances are usually equipped with fixed geometry restrictors, meaning that the solution mass flow rate is driven by the pressure difference across the associated restrictor valve. Results show that gas utilization efficiency (GUE) of the cycles varies between 1.2 and 1.7 for both full and partial loads and vapor exchange (VX) cycle is found to achieve the highest efficiency. It is noticed that, for typical space heating applications, heat pumps operate over a wide range of capacities and thermal lifts. Thus, partially, the novelty introduced in the paper is the investigation based on a seasonal performance approach, following the method prescribed in a recent European standard (EN 12309). The overall result is a modest variation in the seasonal performance for analyzed cycles, from 1.427 (single-effect) to 1.493 (vapor-exchange).

Keywords: absorption cycles, gas utilization efficiency, heat pump, seasonal performance, vapor exchange cycle

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Authors: T. Hadj Sadok, R. Hattab Bey, K. Rebiha

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The valuation of juice from prickly pear of Opuntia ficus indica inermis as cocktails appears an attractive alternative because of their nutritional intake and functional compound has anti-radical activity (polyphenols, vitamin C, carotenoids, Betalaines, fiber and minerals). The juice from the fruit pulp is characterized by a high pH 5.85 which makes it difficult for its conservation and preservation requires a thermal treatment at high temperatures (over 100 °C) harmful for bioactive constituents compared to juice orange more acidic and processed at temperatures < 100 °C. The valuation as fig cocktails-orange is particularly interesting thanks to the contribution of polyph2nols, fiber, vitamin C, reducing sugar (sweetener) and betalaine, minerals while allowing lower temperature processing to decrease pH. The heat treatment of these juices: orange alone or in cocktails showed that the antioxidant power decreases by 12% in presence of 30% of juice treated by the heat and of 28 and 32% in the presence of 10 and 20% juice which shows the effect prickly pear juice of Opuntia. During storage for 4 weeks the loss of vitamin C is 40 and 38% in the presence of 10 and 20% juice and 33% in the presence of 30% pear juice parallel, a treatment of stabilization by heat affects relatively the polyphenols rate which decreases from 10.5% to 30% in the cocktail, and 6.11-6.71pour cocktails at 10% and 20%. Vitamin C decreases to 12 to 24 % after a heat treatment at 85°C for 30 minutes respectively for the orange juice and pear juice; this reduction is higher when the juice is in the form of cocktails composed of 10 to 30 % pear juice.

Keywords: prickly pear juice, orange cocktail, polyphenol, Opuntia ficus indica, vitamin

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Authors: Vaibhav Baliyan, Shweta Mehrotra, S. S. Parihar

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The agricultural productivity is challenged by climate change and depletion in natural resources, including water and land, which significantly affects the crop yield. Wheat is a thermo-sensitive crop and is prone to heat stress. High temperature decreases crop duration, yield attributes, and, subsequently, grain yield and biomass production. Terminal heat stress affects grain filling duration, grain yield, and yield attributes, thus causing a reduction in wheat yield. A field experiment was conducted at Indian Agricultural Research Institute, New Delhi, for two consecutive rabi seasons (2017-18 and 2018-19) on six varieties of wheat (early sown - HD 2967, HD 3086, HD 2894 and late sown - WR 544, HD 3059, HD 3117 ) with three moisture regimes (100%, 80%, and 60% ETc, and no irrigation) and six sowing dates in three replications to investigate the effect of different moisture regimes and sowing dates on growth, yield and water use efficiency of wheat for development of best management practices for mitigation of terminal heat stress. HD3086 and HD3059 gave higher grain yield than others under early sown and late sown conditions, respectively. Maximum soil moisture extraction was recorded from 0-30 cm soil depth across the sowing dates, irrigation regimes, and varieties. Delayed sowing resulted in reducing crop growth period and forced maturity, in turn, led to significant deterioration in all the yield attributing characters and, there by, reduction in yield, suggesting that terminal heat stress had greater impact on yield. Early sowing and irrigation at 80% ETc resulted in improved growth and yield attributes and water use efficiency in both the seasons and helped to some extent in reducing the risk of terminal heat stress of wheat grown on sandy loam soils of semi-arid regions of India.

Keywords: sowing, irrigation, yield, heat stress

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Authors: Hazel James P. Agngarayngay, Arnold R. Elepaño

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Mango is the third most important export fruit in the Philippines. Despite the expanding mango trade in world market, problems on postharvest losses caused by pests and diseases are still prevalent. Many disease control and pest disinfestation methods have been studied and adopted. Heat treatment is necessary to eliminate pests and diseases to be able to pass the quarantine requirements of importing countries. During heat treatments, temperature and time are critical because fruits can easily be damaged by over-exposure to heat. Modeling the process enables researchers and engineers to study the behaviour of temperature distribution within the fruit over time. Understanding physical processes through modeling and simulation also saves time and resources because of reduced experimentation. This research aimed to simulate the heat transfer mechanism and predict the temperature distribution in ‘Carabao' mangoes during hot water treatment (HWT) and extended hot water treatment (EHWT). The simulation was performed in ANSYS CFD Software, using ANSYS CFX Solver. The simulation process involved model creation, mesh generation, defining the physics of the model, solving the problem, and visualizing the results. Boundary conditions consisted of the convective heat transfer coefficient and a constant free stream temperature. The three-dimensional energy equation for transient conditions was numerically solved to obtain heat flux and transient temperature values. The solver utilized finite volume method of discretization. To validate the simulation, actual data were obtained through experiment. The goodness of fit was evaluated using mean temperature difference (MTD). Also, t-test was used to detect significant differences between the data sets. Results showed that the simulations were able to estimate temperatures accurately with MTD of 0.50 and 0.69 °C for the HWT and EHWT, respectively. This indicates good agreement between the simulated and actual temperature values. The data included in the analysis were taken at different locations of probe punctures within the fruit. Moreover, t-tests showed no significant differences between the two data sets. Maximum heat fluxes obtained at the beginning of the treatments were 394.15 and 262.77 J.s-1 for HWT and EHWT, respectively. These values decreased abruptly at the first 10 seconds and gradual decrease was observed thereafter. Data on heat flux is necessary in the design of heaters. If underestimated, the heating component of a certain machine will not be able to provide enough heat required by certain operations. Otherwise, over-estimation will result in wasting of energy and resources. This study demonstrated that the simulation was able to estimate temperatures accurately. Thus, it can be used to evaluate the influence of various treatment conditions on the temperature-time history in mangoes. When combined with information on insect mortality and quality degradation kinetics, it could predict the efficacy of a particular treatment and guide appropriate selection of treatment conditions. The effect of various parameters on heat transfer rates, such as the boundary and initial conditions as well as the thermal properties of the material, can be systematically studied without performing experiments. Furthermore, the use of ANSYS software in modeling and simulation can be explored in modeling various systems and processes.

Keywords: heat transfer, heat treatment, mango, modeling and simulation

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Authors: Juhee Lee, Yongjun Lee

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In designing a low-energy-consuming buildings, the heat transfer through a large glass or wall becomes critical. Multiple layers of the window glasses and walls are employed for the high insulation. The gravity driven air flow between window glasses or wall layers is a natural heat convection phenomenon being a key of the heat transfer. For the first step of the natural heat transfer analysis, in this study the development and application of a finite volume method for the numerical computation of viscous incompressible flows is presented. It will become a part of the natural convection analysis with high-order scheme, multi-grid method, and dual-time step in the future. A finite volume method based on a fully-implicit second-order is used to discretize and solve the fluid flow on unstructured grids composed of arbitrary-shaped cells. The integrations of the governing equation are discretised in the finite volume manner using a collocated arrangement of variables. The convergence of the SIMPLE segregated algorithm for the solution of the coupled nonlinear algebraic equations is accelerated by using a sparse matrix solver such as BiCGSTAB. The method used in the present study is verified by applying it to some flows for which either the numerical solution is known or the solution can be obtained using another numerical technique available in the other researches. The accuracy of the method is assessed through the grid refinement.

Keywords: finite volume method, fluid flow, laminar flow, unstructured grid

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Authors: Harche Rima, Laoufi Nadia Aicha

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This work focuses on the study and modeling of the fouling phenomenon in a vertical pipe. In the first step, milk is one of the fluids obeying the phenomenon of fouling because of the denaturation of these proteins, especially lactoglobulin, which is the active element of milk, and to facilitate its use, we chose to study milk as a fouling fluid. In another step, we consider the test section of our installation as a tubular-type heat exchanger that works against the current and in a closed circuit. A simple mathematical model of Kern & Seaton, based on the kinetics of the fouling resistance, was used to evaluate the influence of the operating parameters (fluid flow velocity and exchange wall temperature) on the fouling resistance. The influence of the variation of the fouling resistance with the operating conditions on the efficiency of the heat exchanger and the importance of the dirty state exchange coefficient as an exchange quality control parameter were discussed and examined. On the other hand, an electronic scanning microscope analysis was performed on the milk deposit in order to obtain its actual image and composition, which allowed us to calculate the thickness of this deposit.

Keywords: fouling, milk, tubular heat exchanger, fouling resistance

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Authors: Orkide Donma, Mustafa M. Donma

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Morbid obesity is a health threatening condition particularly in children. Generally, it leads to the development of metabolic syndrome (MetS) characterized by central obesity, elevated fasting blood glucose (FBG), triglyceride (TRG), blood pressure values and suppressed high density lipoprotein cholesterol (HDL-C) levels. However, some ambiguities exist during the diagnosis of MetS in children below 10 years of age. Therefore, clinicians are in the need of some surrogate markers for the laboratory assessment of pediatric MetS. In this study, the aim is to develop an index, which will be more helpful during the evaluation of further risks detected in morbid obese (MO) children. A total of 235 children with normal body mass index (N-BMI), with varying degrees of obesity; overweight (OW), obese (OB), MO as well as MetS participated in this study. The study was approved by the Institutional Ethical Committee. Informed consent forms were obtained from the parents of the children. Obesity states of the children were classified using BMI percentiles adjusted for age and sex. For the purpose, tabulated data prepared by WHO were used. MetS criteria were defined. Systolic and diastolic blood pressure values were measured. Parameters related to glucose and lipid metabolisms were determined. FBG, insulin (INS), HDL-C, TRG concentrations were determined. Diagnostic Obesity Notation Model Assessment Laboratory (DONMA_LAB) Index [ln TRG/HDL-C*INS] was introduced. Commonly used insulin resistance (IR) indices such as Homeostatic Model Assessment for IR (HOMA-IR) as well as ratios such as TRG/HDL-C, TRG/HDL-C*INS, HDL-C/TRG*INS, TRG/HDL-C*INS/FBG, log, and ln versions of these ratios were calculated. Results were interpreted using statistical package program (SPSS Version 16.0) for Windows. The data were evaluated using appropriate statistical tests. The degree for statistical significance was defined as 0.05. 35 N, 20 OW, 47 OB, 97 MO children and 36 with MetS were investigated. Mean ± SD values of TRG/HDL-C were 1.27 ± 0.69, 1.86 ± 1.08, 2.15 ± 1.22, 2.48 ± 2.35 and 4.61 ± 3.92 for N, OW, OB, MO and MetS children, respectively. Corresponding values for the DONMA_LAB index were 2.17 ± 1.07, 3.01 ± 0.94, 3.41 ± 0.93, 3.43 ± 1.08 and 4.32 ± 1.00. TRG/HDL-C ratio significantly differed between N and MetS groups. On the other hand, DONMA_LAB index exhibited statistically significant differences between N and all the other groups except the OW group. This index was capable of discriminating MO children from those with MetS. Statistically significant elevations were detected in MO children with MetS (p < 0.05). Multiple parameters are commonly used during the assessment of MetS. Upon evaluation of the values obtained for N, OW, OB, MO groups and for MO children with MetS, the [ln TRG/HDL-C*INS] value was unique in discriminating children with MetS.

Keywords: children, index, laboratory, metabolic syndrome, obesity

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Authors: Ujjwala Bhand, Mridula Goel

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Global Competitiveness Index (GCI) prepared by World Economic Forum has become a benchmark in studying the competitiveness of countries and for understanding the factors that enable competitiveness. Innovation is a key pillar in competitiveness and has the unique property of enabling exponential economic growth. This paper attempts to analyze how the pillars comprising the Global Competitiveness Index affect innovation and whether GDP growth can directly affect innovation outcomes for a country. The key objective of the study is to identify areas on which governments of developing countries can focus policies and programs to improve their country’s innovativeness. We have compiled a panel data set for top innovating countries and large emerging economies called BRICS from 2007-08 to 2014-15 in order to find the significant factors that affect innovation. The results of the regression analysis suggest that government should make policies to improve labor market efficiency, establish sophisticated business networks, provide basic health and primary education to its people and strengthen the quality of higher education and training services in the economy. The achievements of smaller economies on innovation suggest that concerted efforts by governments can counter any size related disadvantage, and in fact can provide greater flexibility and speed in encouraging innovation.

Keywords: innovation, global competitiveness index, BRICS, economic growth

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Authors: Chargui Ridha, Agrebi Sameh

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The integration of phase change materials (PCM) for the storage of thermal energy during the period of sunshine before being released during the night is a complement of free energy to improve the system formed by a solar collector, tank storage, and a heat exchanger. This paper is dedicated to the design of a thermal storage tank based on a PCM-based heat exchanger. The work is divided into two parts: an experimental part using paraffin as PCM was carried out within the Laboratory of Thermal Processes of Borj Cedria in order to improve the performance of the system formed by the coupling of a flat solar collector and a thermal storage tank and to subsequently determine the influence of PCM on the whole system. This phase is based on the measurement instrumentation, namely, a differential scanning calorimeter (DSC) and the thermal analyzer (hot disk: HOT DISK) in order to determine the physical properties of the paraffin (PCM), which has been chosen. The second phase involves the detailed design of the PCM heat exchanger, which is incorporated into a thermal storage tank and coupled with a solar air collector installed at the Research and Technology Centre of Energy (CRTEn). A numerical part based on the TRANSYS and Fluent software, as well as the finite volume method, was carried out for the storage reservoir systems in order to determine the temperature distribution in each chosen system.

Keywords: phase change materials, storage tank, heat exchanger, flat plate collector

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Authors: Rosalie Menon, Angela Reid

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Building integrated photovoltaic systems with air collectors (hybrid PV-T) have proved successful however there are few examples of their application in the UK. The opportunity to pull heat from behind the PV system to contribute to a building’s heating system is an efficient use of waste energy and its potential to improve the performance of the PV array is well documented. As part of Glasgow School of Art’s estate expansion, the purchase and redevelopment of an existing 1950’s college building was used as a testing vehicle for the hybrid PV-T system as an integrated element of the upper floor and roof. The primary objective of the feasibility study was to determine if hybrid PV-T was technically and financially suitable for the refurbished building. The key consideration was whether the heat recovered from the PV panels (to increase the electrical efficiency) can be usefully deployed as a heat source within the building. Dynamic thermal modelling (IES) and RetScreen Software were used to carry out the feasibility study not only to simulate overshadowing and optimise the PV-T locations but also to predict the atrium temperature profile; predict the air load for the proposed new 4 No. roof mounted air handling units and to predict the dynamic electrical efficiency of the PV element. The feasibility study demonstrates that there is an energy reduction and carbon saving to be achieved with each hybrid PV-T option however the systems are subject to lengthy payback periods and highlights the need for enhanced government subsidy schemes to reward innovation with this technology in the UK.

Keywords: building integrated, photovoltatic thermal, pre-heat air, ventilation

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Authors: Bassim Shaheen Bachy, Jörg Franke

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In this study, a three dimensional numerical heat transfer model has been used to simulate the laser structuring of polymer substrate material in the Three-Dimensional Molded Interconnect Device (3D MID) which is used in the advanced multi-functional applications. A finite element method (FEM) transient thermal analysis is performed using APDL (ANSYS Parametric Design Language) provided by ANSYS. In this model, the effect of surface heat source was modeled with Gaussian distribution, also the effect of the mixed boundary conditions which consist of convection and radiation heat transfers have been considered in this analysis. The model provides a full description of the temperature distribution, as well as calculates the depth and the width of the groove upon material removal at different set of laser parameters such as laser power and laser speed. This study also includes the experimental procedure to study the effect of laser parameters on the depth and width of the removal groove metal as verification to the modeled results. Good agreement between the experimental and the model results is achieved for a wide range of laser powers. It is found that the quality of the laser structure process is affected by the laser scan speed and laser power. For a high laser structured quality, it is suggested to use laser with high speed and moderate to high laser power.

Keywords: laser structuring, simulation, finite element analysis, thermal modeling

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Authors: Martin Adlington, Boris Ceranic, Sally Shazhad

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In an effort to reduce carbon emissions, changes in UK regulations, such as Part L Conservation of heat and power, dictates improved thermal insulation and enhanced air tightness. These changes were a direct response to the UK Government being fully committed to achieving its carbon targets under the Climate Change Act 2008. The goal is to reduce emissions by at least 80% by 2050. Factors such as climate change are likely to exacerbate the problem of overheating, as this phenomenon expects to increase the frequency of extreme heat events exemplified by stagnant air masses and successive high minimum overnight temperatures. However, climate change is not the only concern relevant to overheating, as research signifies, location, design, and occupation; construction type and layout can also play a part. Because of this growing problem, research shows the possibility of health effects on occupants of buildings could be an issue. Increases in temperature can perhaps have a direct impact on the human body’s ability to retain thermoregulation and therefore the effects of heat-related illnesses such as heat stroke, heat exhaustion, heat syncope and even death can be imminent. This review paper presents a comprehensive evaluation of the current literature on the causes and health effects of overheating in buildings and has examined the differing applied assessment approaches used to measure the concept. Firstly, an overview of the topic was presented followed by an examination of overheating research work from the last decade. These papers form the body of the article and are grouped into a framework matrix summarizing the source material identifying the differing methods of analysis of overheating. Cross case evaluation has identified systematic relationships between different variables within the matrix. Key areas focused on include, building types and country, occupants behavior, health effects, simulation tools, computational methods.

Keywords: overheating, climate change, thermal comfort, health

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Authors: Mina Rouhollahi, J. Boland

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Changes in cities’ heat balance due to rapid urbanization and the urban heat island (UHI) have increased energy demands for space cooling and have resulted in uncomfortable living conditions for urban residents. Climate resilience and comfortable living spaces can be addressed through well-designed urban development. The sustainable housing can be more effective in controlling high levels of urban heat. In Australia, to mitigate the effects of UHIs and summer heat waves, one solution to sustainable housing has been the trend to compact housing design and the construction of energy efficient dwellings. This paper analyses whether current housing configurations and orientations are effective in avoiding increased demands for air conditioning and having an energy efficient residential neighborhood. A significant amount of energy is consumed to ensure thermal comfort in houses. This paper reports on the modelling of heat transfer within the homes using the measurements of radiation, convection and conduction between exterior/interior wall surfaces and outdoor/indoor environment respectively. The simulation was tested on selected 7.5-star energy efficient houses constructed of typical material elements and insulation in Adelaide, Australia. The chosen design dwellings were analyzed in extremely hot weather through one year. The data were obtained via a thermal circuit to accurately model the fundamental heat transfer mechanisms on both boundaries of the house and through the multi-layered wall configurations. The formulation of the Lumped capacitance model was considered in discrete time steps by adopting a non-linear model method. The simulation results focused on the effects of orientation of the solar radiation on the dynamic thermal characteristics of the houses orientations. A high star rating did not necessarily coincide with a decrease in peak demands for cooling. A more effective approach to avoid increasing the demands for air conditioning and energy may be to integrate solar–climatic data to evaluate the performance of energy efficient houses.

Keywords: energy-efficient residential building, heat transfer, neighborhood orientation, solar–climatic data

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Authors: Sara Tokhi Arab, Rozo Noguchi, Tofeal Ahamed

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Drought is a natural disaster that occurs in a region due to a lack of precipitation and high temperatures over a continuous period or in a single season as a consequence of climate change. Precipitation deficits and prolonged high temperatures mostly affect the agricultural sector, water resources, socioeconomics, and the environment. Consequently, it causes agricultural product loss, food shortage, famines, migration, and natural resources degradation in a region. Agriculture is the first sector affected by drought. Therefore, it is important to develop an agricultural drought risk and loss assessment to mitigate the drought impact in the agriculture sector. In this context, the main purpose of this study was to assess yield loss using composite drought indices in the drought-affected vineyards. In this study, the CDI was developed for the years 2016 to 2020 by comprising five indices: the vegetation condition index (VCI), temperature condition index (TCI), deviation of NDVI from the long-term mean (NDVI DEV), normalized difference moisture index (NDMI) and precipitation condition index (PCI). Moreover, the quantitative principal component analysis (PCA) approach was used to assign a weight for each input parameter, and then the weights of all the indices were combined into one composite drought index. Finally, Bayesian regularized artificial neural networks (BRANNs) were used to evaluate the yield variation in each affected vineyard. The composite drought index result indicated the moderate to severe droughts were observed across the Kabul Province during 2016 and 2018. Moreover, the results showed that there was no vineyard in extreme drought conditions. Therefore, we only considered the severe and moderated condition. According to the BRANNs results R=0.87 and R=0.94 in severe drought conditions for the years of 2016 and 2018 and the R= 0.85 and R=0.91 in moderate drought conditions for the years of 2016 and 2018, respectively. In the Kabul Province within the two years drought periods, there was a significate deficit in the vineyards. According to the findings, 2018 had the highest rate of loss almost -7 ton/ha. However, in 2016 the loss rates were about – 1.2 ton/ha. This research will support stakeholders to identify drought affect vineyards and support farmers during severe drought.

Keywords: grapes, composite drought index, yield loss, satellite remote sensing

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Authors: Iacopo Testi, Diego Pajarito, Nicoletta Roberto, Carmen Greco

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Today, a consistent segment of the world’s population lives in urban areas, and this proportion will vastly increase in the next decades. Therefore, understanding the key trends in urbanization, likely to unfold over the coming years, is crucial to the implementation of sustainable urban strategies. In parallel, the daily amount of digital data produced will be expanding at an exponential rate during the following years. The analysis of various types of data sets and its derived applications have incredible potential across different crucial sectors such as healthcare, housing, transportation, energy, and education. Nevertheless, in city development, architects and urban planners appear to rely mostly on traditional and analogical techniques of data collection. This paper investigates the prospective of the data science field, appearing to be a formidable resource to assist city managers in identifying strategies to enhance the social, economic, and environmental sustainability of our urban areas. The collection of different new layers of information would definitely enhance planners' capabilities to comprehend more in-depth urban phenomena such as gentrification, land use definition, mobility, or critical infrastructural issues. Specifically, the research results correlate economic, commercial, demographic, and housing data with the purpose of defining the youth economic discomfort index. The statistical composite index provides insights regarding the economic disadvantage of citizens aged between 18 years and 29 years, and results clearly display that central urban zones and more disadvantaged than peripheral ones. The experimental set up selected the city of Rome as the testing ground of the whole investigation. The methodology aims at applying statistical and spatial analysis to construct a composite index supporting informed data-driven decisions for urban planning.

Keywords: data science, spatial analysis, composite index, Rome, urban planning, youth economic discomfort index

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Authors: Tran Dinh Lan, Do Thi Thu Huong

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Among the 17 goals of the United Nations, 2030 Agenda for Sustainable Development, SDG 14.2 and SDG 14.4 under SDG 14 directly address the sustainable management, exploitation, and use of marine ecosystems. To achieve these goals, it is necessary to quantify the level of sustainable use of marine ecosystems, which have been paid attention for more than two decades in the direction of a quantitative approach by indicator and index development using methods of building and analyzing indicators and indices. With the employment of the above methods, over the past two decades, a number of marine ecosystems in Vietnam have been quantitatively evaluated for sustainable use for integrated coastal and marine management. Thirty indicators for sustainable use of marine ecosystems in the Northeast of Vietnam, together with indices, have been developed to assess mangrove, coral, and beach ecosystems. An assessment shows the following results. The mangrove ecosystem declined from sustainable to unsustainable uses in the period 1989-2007. The coral ecosystem in 2003 was at a sensitive point between sustainable and unsustainable uses. The beach ecosystem was evaluated with ten selected beaches in the period 2013-2018, showing that nine beaches are at a sustainable level, and one beach is at an unsustainable level. The Thua Thien-Hue coastal lagoon ecosystem assessed by 21 indicators of environmental vulnerability in 2014 showed less sustainability. The marine ecosystems around the offshore islands of Bach Long Vi, Con Co, and Tho Chu were tested to assess the level of sustainable use by the index of total economic value. The results show that these ecosystems are being used sustainably but are also at risk of falling to an unsustainable level (Tho Chu). The use of the environmental vulnerability index or economic value index to evaluate ecosystem sustainability only reflects parts of the function or value of the system but does not fully reflect the sustainability of the system.

Keywords: index, indicators, sustainability evaluation, Vietnam marine ecosystems

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