Search results for: Young Lives Study (YLS)

Authors: Liqiang Duan, Ma Jingkai, Lv Zhipeng, Haifan Cai

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The integrated solar combined cycle (ISCC) system has a series of advantages such as increasing the system power generation, reducing the cost of solar power generation, less pollutant and CO₂ emission. In this paper, the parabolic trough collectors with direct steam generation (DSG) technology are considered to replace the heat load of heating surfaces in heat regenerator steam generation (HRSG) of a conventional natural gas combined cycle (NGCC) system containing a PG9351FA gas turbine and a triple pressure HRSG with reheat. The detailed model of the NGCC system is built in ASPEN PLUS software and the parabolic trough collectors with DSG technology is modeled in EBSILON software. ISCC-DSG systems with the replacement of single, two, three and four heating surfaces are studied in this paper. Results show that: (1) the ISCC-DSG systems with the replacement heat load of HPB, HPB+LPE, HPE2+HPB+HPS, HPE1+HPE2+ HPB+HPS are the best integration schemes when single, two, three and four stages of heating surfaces are partly replaced by the parabolic trough solar energy collectors with DSG technology. (2) Both the changes of feed water flow and the heat load of the heating surfaces in ISCC-DSG systems with the replacement of multi-stage heating surfaces are smaller than those in ISCC-DSG systems with the replacement of single heating surface. (3) ISCC-DSG systems with the replacement of HPB+LPE heating surfaces can increase the solar power output significantly. (4) The ISCC-DSG systems with the replacement of HPB heating surfaces has the highest solar-thermal-to-electricity efficiency (47.45%) and the solar radiation energy-to-electricity efficiency (30.37%), as well as the highest exergy efficiency of solar field (33.61%).

Keywords: HRSG, integration scheme, parabolic trough collectors with DSG technology, solar power generation

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Authors: Zheng Ruoyuan

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With the rapid development of economic globalization and increasingly fierce international competition, multinational companies have carried out investment strategy shifts and innovations, and actively promoted localization strategies. Localization strategies have become the main trend in the development of multinational companies. Large-scale entry of multinational companies China has a history of more than 20 years. With the sustained and steady growth of China's economy and the optimization of the investment environment, multinational companies' investment in China has expanded rapidly, which has also had an important impact on the Chinese economy: promoting employment, foreign exchange reserves, and improving the system. etc., has brought a lot of high-tech and advanced management experience; but it has also brought challenges and survival pressure to China's local enterprises. In recent years, multinational companies have gradually regarded China as an important part of their global strategies and began to invest in China. Actively promote localization strategies, including production, marketing, scientific research and development, etc. Many multinational companies have achieved good results in localized operations in China. Not only have their benefits continued to improve, but they have also established a good corporate image and brand in China. image, which has greatly improved their competitiveness in the international market. However, there are also some multinational companies that have difficulties in localized operations in China. This article will closely follow the background of economic globalization and comprehensively use the theory of multinational companies and strategic management theory and business management theory, using data and facts as the entry point, combined with typical cases of representative significance for analysis, to conduct a systematic study of the localized operations of multinational companies in China. At the same time, for each specific link of the operation of multinational companies, we provide multinational enterprises with some inspirations and references.

Keywords: localization, business management, multinational, marketing

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Authors: Surya Prasad Sharma, Suyash Katdare, Syed Ainul Hussain

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Human-induced factors contributed to the population decline of crocodylians in India which became evident by the mid-20th century when authorities forewarned the extinction risk for the crocodile and proposed regulation in the crocodile trade. The proposed action led to the enactment of national and international wildlife regulations to prohibit the trade-in of crocodile skins and parts. Subsequently, conservation translocation programs were initiated to restore the species in the wild through a 'head-start' approach. In India, the crocodile conservation program, which began in the early 1970s, has been one of India's longest-running conservation initiatives. The gharial (Gavialis gangeticus) population has benefitted, and the gharial number increased rapidly owing to these efforts. The immediate risk of extinction was averted as the gharial has recovered due to decades-long cumulative conservation efforts, the consideration of the genetic for monitoring the recovery of the recovered populations is still lacking. Hence, we assessed the genetic diversity of the Girwa gharial population in India using six polymorphic nuclear microsatellites loci and mitochondrial control region. The number of alleles per loci ranged between 2 to 5, and the allelic richness (Ar) was 2.67 ± 0.49, and the observed (Ho) and expected (He) heterozygosities were 0.42 ± 0.08 and 0.42 ± 0.09, respectively. The M-ratio yielded a value of (0.41 ± 0.16) lower than critical M, suggesting a genetic bottleneck in the Girwa population. We observed more mitochondrial control region haplotypes in the Girwa population than previously reported in the largest gharial population in the Chambal River. Overall, our study indicates that genetic diversity remains low despite the recovery in the Girwa population. Hence, we recommend a range-wide genetic assessment of gharial populations using high-throughput techniques to identify the source population and plan future translocation programs.

Keywords: conservation translocation, recovery, crocodile, bottleneck

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Authors: Kristina Jansen, Maximilian Lennartz, Patrick Lebok, Guido Sauter, Ronald Simon, David Dum, Stefan Steurer

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DOG1 (Discovered on GIST1) is a voltage-gated calcium-activated chloride and bicarbonate channel that is highly expressed in interstitial cells of Cajal and in gastrointestinal stromal tumors (GIST) derived from Cajal cells. To systematically determine in what tumor entities and normal tissue types DOG1 may be further expressed, a tissue microarray (TMA) containing 15,965 samples from 121 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types were analyzed by immunohistochemistry. DOG1 immunostaining was found in 67 tumor types, including GIST (95.7%), esophageal squamous cell carcinoma (31.9%), pancreatic ductal adenocarcinoma (33.6%), adenocarcinoma of the Papilla Vateri (20%), squamous cell carcinoma of the vulva (15.8%) and the oral cavity (15.3%), mucinous ovarian cancer (15.3%), esophageal adenocarcinoma (12.5%), endometrioid endometrial cancer (12.1%), neuroendocrine carcinoma of the colon (11.1%) and diffuse gastric adenocarcinoma (11%). Low level-DOG1 immunostaining was seen in 17 additional tumor entities. DOG1 expression was unrelated to histopathological parameters of tumor aggressiveness and/or patient prognosis in cancers of the breast (n=1,002), urinary bladder (975), ovary (469), endometrium (173), stomach (233), and thyroid gland (512). High DOG1 expression was linked to estrogen receptor expression in breast cancer (p<0.0001) and the absence of HPV infection in squamous cell carcinomas (p=0.0008). In conclusion, our data identify several tumor entities that can show DOG1 expression levels at similar levels as in GIST. Although DOG1 is tightly linked to a diagnosis of GIST in spindle cell tumors, the differential diagnosis is much broader in DOG1 positive epithelioid neoplasms.

Keywords: biomarker, DOG1, immunohistochemistry, tissue microarray

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Authors: Florge Francis A. Sy

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Physicians develop emotional and psychological distress after facing a patient’s death. This can result in stress or burnout. Coping mechanisms in dealing with these deaths may be maladaptive. Determining grief, emotional impact, and coping strategies in physicians is necessary to identify those needing intervention. This can be done by employing validated assessment tools such as the Texas Revised Inventory of Grief (TRIG) scale, Impact of Events Scale (IES), and BriefCOPE tool, respectively. This prospective, observational study was done in a private hospital in Cebu City. Fifty-five internal medicine residents were included and tasked to answer a survey based on their most memorable patient death encounter. The TRIG, IES, and BriefCOPE scores were determined. Participants were divided into severe grief and non-severe grief based on TRIG scores, low-impact, moderate-impact, and high-impact based on IES, and low-use, moderate-use, and high-use based on the BriefCOPE. The differences in the groups’ characteristics were statistically determined, and a p-value of < 0.05 was significant. The participants’ average age was 28.45 years. Most were female and single. Most belonged to the non-severe group based on TRIG, a moderate-impact group based on the IES, and high-use group based on the BriefCOPE. However, 21.8% reported severe grief, 27.3% reported high-impact, and 10.9% had low use of coping strategies. The proportion of residents who encountered CPR prior to the patient’s death was greater in the severe group. Proportions of both high-impact and non-high impact groups were comparable. The proportion of female residents was higher in the high-use group. There were a number of residents who reported severe grief, high emotional impact, and low coping strategies. This highlights the need for interventions such as debriefing after CPR or formal training in residency programs in dealing with emotional burden to counteract maladaptive coping behaviors and prevent negative outcomes.

Keywords: residents, grief, emotional impact, coping, patient death

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Authors: Zahra Ashraf

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Flax and pumpkin seeds are a rich source of unsaturated fatty acids, antioxidants and fiber, known to have anti-atherogenic properties. Hypercholesterolemia is a state characterized by the elevated level of cholesterol in the blood. This research was designed to study the effect of flax and pumpkin seeds powder mixture on hypercholesterolemia and body weight. Rat’s species were selected as human representative. Thirty male albino rats were divided into three groups: a control group, a CD-chol group (control diet+cholesterol) fed with 1.5% cholesterol and FP-chol group (flaxseed and pumpkin seed powder+ cholesterol) fed with 1.5% cholesterol. Flax and pumpkin seed powder mixed at proportion of (5/1) (omega-3 and omega-6). Blood samples were collected to examine lipid profile and body weight was also measured. Thus the data was subjected to analysis of variance. In CD-chol group, body weight, total cholesterol TC, triacylglycerides TG in plasma, plasma LDL-C, ratio significantly increased with a decrease in plasma HDL (good cholesterol). In FP-chol group lipid parameters and body weights were decreased significantly with an increase in HDL and decrease in LDL (bad cholesterol). The mean values of body weight, total cholesterol, triglycerides, low density lipoprotein and high density lipoproteins in FP-chol group were 240.66±11.35g, 59.60±2.20mg/dl, 50.20±1.79 mg/dl, 36.20±1.62mg/dl, 36.40±2.20 mg/dl, respectively. Flaxseed and pumpkin seeds powder mixture showed reduction in body weight, serum cholesterol, low density lipoprotein and triglycerides. While significant increase was shown in high density lipoproteins when given to hypercholesterolemic rats. Our results suggested that flax and pumpkin seed mixture has hypocholesterolemic effects which were probably mediated by polyunsaturated fatty acids (omega-3 and omega-6) present in seed mixture.

Keywords: hypercolesterolemia, omega 3 and omega 6 fatty acids, cardiovascular diseases

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Authors: Mohadese Sukhtesaraii, Mohammad Esmail Esmaili Jelodar, Kosar Sookhtesaraii

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Throughout history, humans have always wanted to have a shelter to live in, and this need and desire became the beginning of building and architecture. It was necessary to build a shelter and a building, dealing with the surrounding nature. The design and construction of architectural spaces are always influenced by nature, climate, and geographical location, and It is believed clearly see this influence even in the use of materials used in the construction of architectural buildings. The historical port of Siraf is located on the northern coast of the Persian Gulf in Bushehr province and 38 km from Kangan port. Geographically and climatically, Siraf is considered one of the hot and humid areas. The Zagros mountains, which continue from the Iranian plateau to the sea, end at Bandar Siraf; As a result, it creates a strip one kilometer wide by the sea. The location of Siraf in the restrictive conditions of the mountains and the sea has made it impossible to expand the city. The main goal of the current research is to investigate the climate of Siraf and the influence of the region's climate on the architecture and design of residential buildings in Siraf, known as noble houses, in the early Islamic centuries. In this research, it is looking for an answer to the question of how the climatic and geographical conditions have affected the architecture of Siraf buildings. The theoretical framework of this research can be expressed based on the influence of climate on the historical architecture of Bandar Seraf and the spatial analysis of archeology. Also, the research method will be analytical-descriptive and using field and library studies. The authors of the article believe that the architectural spaces of the early Islamic centuries of Siraf city were affected by the climate and geographical location, and the architects started building buildings by considering factors such as the sun's radiation, wind direction, and the position of the mountains and the sea. To use the regional and environmental potential for buildings.

Keywords: hose N, noble hose, islamic era, siraf, climate

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Authors: Muhammad Tufail, Jawad Hussain, Hammad Hussain, Imran Hafeez, Naveed Ahmad

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Road safety performance index is a composite index which combines various indicators of road safety into single number. Development of a road safety performance index using appropriate safety performance indicators is essential to enhance road safety. However, a road safety performance index in developing countries has not been given as much priority as needed. The primary objective of this research is to develop a general Road Safety Performance Index (RSPI) for developing countries based on the facility as well as behavior of road user. The secondary objectives include finding the critical inputs in the RSPI and finding the better method of making the index. In this study, the RSPI is developed by selecting four main safety performance indicators i.e., protective system (seat belt, helmet etc.), road (road width, signalized intersections, number of lanes, speed limit), number of pedestrians, and number of vehicles. Data on these four safety performance indicators were collected using observation survey on a 20 km road section of the National Highway N-125 road Taxila, Pakistan. For the development of this composite index, two methods are used: a) Principal Component Analysis (PCA) and b) Equal Weighting (EW) method. PCA is used for extraction, weighting, and linear aggregation of indicators to obtain a single value. An individual index score was calculated for each road section by multiplication of weights and standardized values of each safety performance indicator. However, Simple Average technique was used for weighting and linear aggregation of indicators to develop a RSPI. The road sections are ranked according to RSPI scores using both methods. The two weighting methods are compared, and the PCA method is found to be much more reliable than the Simple Average Technique.

Keywords: indicators, aggregation, principle component analysis, weighting, index score

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Authors: Yanling Li, Linying Ji, Zita Oravecz, Timothy R. Brick, Michael D. Hunter, Sy-Miin Chow

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Assessing several individuals intensively over time yields intensive longitudinal data (ILD). Even though ILD provide rich information, they also bring other data analytic challenges. One of these is the increased occurrence of missingness with increased study length, possibly under non-ignorable missingness scenarios. Multiple imputation (MI) handles missing data by creating several imputed data sets, and pooling the estimation results across imputed data sets to yield final estimates for inferential purposes. In this article, we introduce dynr.mi(), a function in the R package, Dynamic Modeling in R (dynr). The package dynr provides a suite of fast and accessible functions for estimating and visualizing the results from fitting linear and nonlinear dynamic systems models in discrete as well as continuous time. By integrating the estimation functions in dynr and the MI procedures available from the R package, Multivariate Imputation by Chained Equations (MICE), the dynr.mi() routine is designed to handle possibly non-ignorable missingness in the dependent variables and/or covariates in a user-specified dynamic systems model via MI, with convergence diagnostic check. We utilized dynr.mi() to examine, in the context of a vector autoregressive model, the relationships among individuals’ ambulatory physiological measures, and self-report affect valence and arousal. The results from MI were compared to those from listwise deletion of entries with missingness in the covariates. When we determined the number of iterations based on the convergence diagnostics available from dynr.mi(), differences in the statistical significance of the covariate parameters were observed between the listwise deletion and MI approaches. These results underscore the importance of considering diagnostic information in the implementation of MI procedures.

Keywords: dynamic modeling, missing data, mobility, multiple imputation

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Authors: Hossein Tavallali, Mohammad Ali Karimi, Gohar Deilamy-Rad

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In this study, a new type of alumina-coated magnetite nanoparticles (Fe3O4/Al2O3 NPs) with sodium dodecyl sulfate- 1-(2-pyridylazo)-2-naphthol (SDS-PAN) as a new sorbent solid phase extraction (SPE) has been successfully synthesized and applied for preconcentration and separation of Cd and Pb in environmental samples. Compared with conventional SPE methods, the advantages of this new magnetic Mixed Hemimicelles Solid-Phase Extraction Procedure (MMHSPE) still include easy preparation and regeneration of sorbents, short times of sample pretreatment, high extraction yields, and high breakthrough volumes. It shows great analytical potential in preconcentration of Cd and Pb compounds from large volume water samples. Due to the high surface area of these new sorbents and the excellent adsorption capacity after surface modification by SDS-PAN, satisfactory concentration factor and extraction recoveries can be produced with only 0.05 g Fe3O4/Al2O3 NPs. The metals were eluted with 3mL HNO3 2 mol L-1 directly and detected with the detection system Flame Atomic Absorption Spectrometry (FAAS). Various influencing parameters on the separation and preconcentration of trace metals, such as the amount of PAN, pH value, sample volume, standing time, desorption solvent and maximal extraction volume, amount of sorbent and concentration of eluent, were studied. The detection limits of this method for Cd and Pb were 0.3 and 0.7 ng mL−1 and the R.S.D.s were 3.4 and 2.8% (C = 28.00 ng mL-1, n = 6), respectively. The preconcentration factor of the modified nanoparticles was 166.6. The proposed method has been applied to the determination of these metal ions at trace levels in soil, river, tap, mineral, spring and wastewater samples with satisfactory results.

Keywords: Alumina-coated magnetite nanoparticles, Magnetic Mixed Hemimicell Solid-Phase Extraction, Cd and Pb, soil sample

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Authors: Nagui A. Abdel-Khalek, Khaled A. Selim, Ahmed Hamdy

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Kaolin is naturally occurring ore predominantly containing kaolinite mineral in addition to some gangue minerals. Typical impurities present in kaolin ore are quartz, iron oxides, titanoferrous minerals, mica, feldspar, organic matter, etc. The main coloring impurity, particularly in the ultrafine size range, is titanoferrous minerals. Kaolin is used in many industrial applications such as sanitary ware, table ware, ceramic, paint, and paper industries, each of which should be of certain specifications. For most industrial applications, kaolin should be processed to obtain refined clay so as to match with standard specifications. For example, kaolin used in paper and paint industries need to be of high brightness and low yellowness. Egyptian kaolin is not subjected to any beneficiation process and the Egyptian companies apply selective mining followed by, in some localities, crushing and size reduction only. Such low quality kaolin can be used in refractory and pottery production but not in white ware and paper industries. This paper aims to study the amenability of beneficiation of an Egyptian kaolin ore of El-Teih locality, Sinai, to be suitable for different industrial applications. Attrition scrubbing and classification followed by magnetic separation are applied to remove the associated impurities. Attrition scrubbing and classification are used to separate the coarse silica and feldspars. Wet high intensity magnetic separation was applied to remove colored contaminants such as iron oxide and titanium oxide. Different variables affecting of magnetic separation process such as solid percent, magnetic field, matrix loading capacity, and retention time are studied. The results indicated that substantial decrease in iron oxide (from 1.69% to 0.61% ) and TiO2 (from 3.1% to 0.83%) contents as well as improving iso-brightness (from 63.76% to 75.21% and whiteness (from 79.85% to 86.72%) of the product can be achieved.

Keywords: Kaolin, titanoferrous minerals, beneficiation, magnetic separation, attrition scrubbing, classification

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Authors: Zainab A. Alaghbri, Labiba A., Esam A.

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Tuberculosis (TB) is the fourth leading cause of death in Yemen and is considered a major priority by the Ministry of Public Health. The war in Yemen has led to the emergence of one of the worst humanitarian crises in the world. These circumstances may lead to exacerbate the situation of tuberculosis. This study aims to describe the trend and incidence of TB in north and east governorates, Yemen 2019-2021 and provide recommendations for interventions. A descriptive analysis was conducted during July to September 2022. Data of TB cases were obtained from the national tuberculosis program as soft copy. The Data included the TB case collected and diagnosed during 2019-2021. The data contains the following variables: Sex, age, governorates, smear-positive cases, extra-pulmonary cases, and treatment outcomes. 16791 TB cases were notified for an overall case notification rate 65.5/100000 for all forms (smear positive and Extra-pulmonary), There was a slightly declined in 2020 and 2021 by 1%. Both the pulmonary smear positive and Extra pulmonary rates were slightly decreased from 8.8 to 7.7 and 13.5 to 12.8 / 100, 000 populations respectively. For Tuberculosis cases by type of patient, the incidence of extra-pulmonary was the highest (12,9, 11.3 and 12,2/100000) over the three years. However, the incidence of pulmonary failure was the lowest. The majority of cases were in the age group 25-34. The overall treatment success rate for smear-positive patients was 88%. Of the 627 patients with documented unsuccessful outcomes (e.g., failure, death, and default), 165 (23%) died, 52 (8.3%) failed treatment, and 410 (65%) defaulted. Overall, the magnitude of tuberculosis decreased over the periods reviewed. The proportion of Extra-pulmonary TB was the highest. The success rate achieved after treatment was below the levels established by the WHO End Tuberculosis Strategy (90%). Failure to complete treatment may be responsible for the low success rate. Monitoring and addressing the risk factors that were associated with treatment outcomes and duration may help improve the likelihood of achieving favorable outcomes among cases of smear-positive pulmonary TB.

Keywords: tuberculosis, trend, incidence, yemen

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Authors: Mahzabin Afroz, Indubhushan Patnaikuni, Srikanth Venkatesan

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It is well-known that fly ash can be used in high volume as a partial replacement of cement to get beneficial effects on concrete. High volume fly ash (HVFA) concrete is currently emerging as a popular option to strengthen by fiber. Although studies have supported the use of fibers with fly ash, a unified model along with the incorporation into finite element software package to estimate the maximum flexural loads need to be developed. In this study, nonlinear finite element analysis of steel fiber reinforced high strength HVFA concrete beam under static loadings was conducted to investigate their failure modes in terms of ultimate load. First of all, the experimental investigation of mechanical properties of high strength HVFA concrete was done and validates with developed numerical model with the appropriate modeling of element size and mesh by ANSYS 16.2. To model the fiber within the concrete, three-dimensional random fiber distribution was simulated by spherical coordinate system. Three types of high strength HVFA concrete beams were analyzed reinforced with 0.5, 1 and 1.5% volume fractions of steel fibers with specific mechanical and physical properties. The result reveals that the use of nonlinear finite element analysis technique and three-dimensional random fiber orientation exhibited fairly good agreement with the experimental results of flexural strength, load deflection and crack propagation mechanism. By utilizing this improved model, it is possible to determine the flexural behavior of different types and proportions of steel fiber reinforced HVFA concrete beam under static load. So, this paper has the originality to predict the flexural properties of steel fiber reinforced high strength HVFA concrete by numerical simulations.

Keywords: finite element analysis, high volume fly ash, steel fibers, spherical coordinate system

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Authors: Marcio S. da Silva, Jose Mauricio de B. Bezerra, Antonio E. de A. Nogueira

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This paper aims to make a performance analysis of shield wire transmission lines against atmospheric discharges when it is made the option of sectioning the shield wire and verify if the tolerability of the change. As a goal of this work, it was established to make complete modeling of a transmission line in the ATPDraw program with shield wire grounded in all the towers and in some towers. The methodology used to make the proposed evaluation was to choose an actual transmission line that served as a case study. From the choice of transmission line and verification of all its topology and materials, complete modeling of the line using the ATPDraw software was performed. Then several atmospheric discharges were simulated by striking the grounded shield wires in each tower. These simulations served to identify the behavior of the existing line against atmospheric discharges. After this first analysis, the same line was reconsidered with shield wire segmentation. The shielding wire segmentation technique aims to reduce induced losses in shield wires and is adopted in some transmission lines in Brazil. With the same conditions of atmospheric discharge the transmission line, this time with shield wire segmentation was again evaluated. The results obtained showed that it is possible to obtain similar performances against atmospheric discharges between a shield wired line in multiple towers and the same line with shield wire segmentation if some precautions are adopted as verification of the ground resistance of the wire segmented shield, adequacy of the maximum length of the segmented gap, evaluation of the separation length of the electrodes of the insulator spark, among others. As a conclusion, it is verified that since the correct assessment and adopted the correct criteria of adjustment a transmission line with shielded wire segmentation can perform very similar to the traditional use with multiple earths. This solution contributes in a very important way to the reduction of energy losses in transmission lines.

Keywords: atmospheric discharges, ATPDraw, shield wire, transmission lines

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Authors: George Obinna Akuaka

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Solid waste disposal techniques in Nigeria pose an environmental threat to the environment and to nearby resident. The presence of microbial physical and chemical concentration in boreholes samples nearby dumpsite implies that groundwater is normally contaminated by leachate infiltration from an open landfill dumpsite. In this study, the physicochemical and microbial analyses of water samples from hand dug well in the site and boreholes were carried out around the active landfill and from different distances (50 m to 200 m). leachate samples collected were used to ascertain the effect or extent of contamination on the groundwater quality. A total of 5 leachate samples and 5 samples of groundwater were collected, and all samples were analyzed for various physical and chemical parameters according to the standard methods. These include pH, Electrical conductivity, Total dissolved solid, BOD, OD, Temperature, major cations such as Mg²+ Ca²+, Fe²+ Cu²+, major anions NO³-, Cl-,SO⁴- PO⁴-, Zn, Ar, Cd, Cr, Hg, Pb, Ni are the heavy metals and metalloids. The mean values of the physical and chemical parameters obtained from both sites were compared with the established of the World Health Organization (WHO). The leachate samples were found to be higher in the concentration of the results obtained than that of the boreholes water, and the recorded mean values of heavy metals were above approved standard minimum limits. The results indicated that mercury and copper were not found in all the borehole water samples. Microbial analyses showed that total heterotrophic bacteria mean count ranged from 10.6 X10⁷ cfu/ml to 2.04x10⁷cfu/ml and 9.5 X 10⁷ cfu/ml to 18.9 X 10⁷ cfu/ml in leachate and borehole samples respectively. It also revealed that almost at the bacteria isolated in the leachate were also found in the water samples. This results indicated that heavy pollution in all the samples with most physicochemical parameters and microbes showed traceable pollution, which occurred as a result of leachate infiltration into the ground water.

Keywords: physicochemical, landfill dumpsite, microbial, leachate, groundwater

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Authors: Fazil Hasan, M. Shafiq Ansari, Mohammad Muslim

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Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae) is an exotic insect and effective biocontrol agent of Parthenium hysterophorus L. (Asteraceae). Our study aimed to determine the induction and termination of diapause, in response to abiotic (temperature and moisture) and biotic factors (age and reproductive status) and the effect of diapause on adult longevity and female fecundity. The adults burrowed into the soil about 1–6 cm below the surface for diapause at any time from July to December with a peak of 70% in the 2nd week of December at Aligarh region, India. The termination of diapause took place in May and June with the commencement of monsoon rains. Non-diapausing adults were also capable of breeding during winter under laboratory conditions. There was a significantly increased in the percentage of diapaused adults in subsequent generation i.e. 4% in F1 generation and 90% in F7 generation. The percentage of diapause was also significantly increased with age of adults. It has a positive effect on female fecundity as compared to the fecundity in pre-diapaused duration. Experiments proved that soil moisture played an important role in providing the conditions for initiation and termination of diapause. The adults which undergone diapause in January and February were continuously exposed to 35º, 40º and 45º C for one week and a daily dose of 10 and 8 hours for 6 and 5 days, respectively resulting in termination of diapause. This method may be used to initiate mass multiplication for carrying out releases early in the season. Exposure of adults to extremely low temperatures i.e. 5º and 10º C induced 94.3% and 92.5% diapause, respectively with no adult mortality. Therefore, low temperatures can also be used as a medium for the storage of mass reared beetles for a long time without having negative effect on their longevity and fecundity. Thus, our findings are of great utility in the biological suppression of P. hysterophorus as it will enhance the effectiveness of this beetle through manipulation of diapause.

Keywords: Zygogramma bicolorata, environmental factors, age, sex, diapause, Parthenium hysterophorus, biocontrol

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Authors: Raj Raghupathy

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Recurrent Spontaneous Miscarriage (RSM) is a common form of pregnancy loss, 50% of which are due to ‘unexplained’ causes. Evidence exists to suggest that RSM may be caused by immunologic factors such as cytokines which are critical molecules of the immune system, with an impressive array of capabilities. An association appears to exist between Th2-type reactivity (mediated by Th2 or anti-inflammatory cytokines) and normal, successful pregnancy, and between unexplained RSM and Th1 cytokine dominance. If pro-inflammatory cytokines are indeed associated with pregnancy loss, the suppression of these cytokines, and thus the ‘redirection’ of maternal reactivity, may help prevent cytokine-mediated pregnancy loss. The objective of this study was to explore the possibility of modulating cytokine production using Dydrogesterone (Duphaston®), an orally-administered progestogen. Peripheral blood mononuclear cells from 34 women with a history of at least 3 unexplained recurrent miscarriages were stimulated in vitro with a mitogen (to elicit cytokine production) in the presence and absence of dydrogesterone. Levels of selected pro- and anti-inflammatory cytokines produced by peripheral blood mononuclear cells were measured after exposure to these progestogens. Dydrogesterone down-regulates the production of pro-inflammatory cytokines and up-regulates the production of anti-inflammatory cytokines. The ratios of Th2 to Th1 cytokines are markedly elevated in the presence of dydrogesterone, indicating a shift from potentially harmful maternal Th1 reactivity to a more pregnancy-conducive Th2 profile. We used a progesterone receptor antagonist to show that this cytokine-modulating effect of dydrogesterone is mediated via the progesterone receptor. Dydrogesterone also induces the production of the Progesterone-Induced Blocking Factor (PIBF); lymphocytes exposed to PIBF produce higher levels of Th2 cytokines, affecting a Th1 → Th2 cytokine shift which could be favourable to the success of pregnancy. We conclude that modulation of maternal cytokine production profiles is possible with dydrogesterone which has the merits that it can be administered orally and that it is safe.

Keywords: cytokines, dydrogesterone, progesterone, recurrent spontaneous miscarriage

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Authors: Jantakan Jullawateelert, Korakod Haonoo, Sutipong Sananseang, Sarun Torpaiboon, Thanunthon Bowornsakulwong, Lalintip Hocharoen

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Process scale-up is essential for the biological process to increase production capacity from bench-scale bioreactors to either pilot or commercial production. Scale-up based on constant volumetric oxygen mass transfer coefficient (KLa) is mostly used as a scale-up factor since oxygen supply is one of the key limiting factors for cell growth. However, to estimate KLa of culture vessels operated with different conditions are time-consuming since it is considerably influenced by a lot of factors. To overcome the issue, this study aimed to establish correlation equations of KLa and operating parameters in 0.5 L and 5 L bioreactor employed with pitched-blade impeller and gas sparger. Temperature, gas flow rate, agitation speed, and impeller position were selected as process parameters and equations were created using response surface methodology (RSM) based on central composite design (CCD). In addition, the effects of these parameters on KLa were also investigated. Based on RSM, second-order polynomial models for 0.5 L and 5 L bioreactor were obtained with an acceptable determination coefficient (R²) as 0.9736 and 0.9190, respectively. These models were validated, and experimental values showed differences less than 10% from the predicted values. Moreover, RSM revealed that gas flow rate is the most significant parameter while temperature and agitation speed were also found to greatly affect the KLa in both bioreactors. Nevertheless, impeller position was shown to influence KLa in only 5L system. To sum up, these modeled correlations can be used to accurately predict KLa within the specified range of process parameters of two different sizes of bioreactors for further scale-up application.

Keywords: response surface methodology, scale-up, stirred-tank bioreactor, volumetric oxygen mass transfer coefficient

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Authors: Hai Zhou, Wenzhi Zhao

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Water is one of the most important factors limiting plant growth and development in desert ecosystems. In order to understand how desert shrubs cope with variation in water sources over time, it is important to understand plant–water relations in desert-oasis ecotone. We selected the typical desert shrubs: Nitraria sibirica, Calligonum mongolicum and Haloxylon ammodendron of 5-, 10-, 20- and 40-year old as the research species, to study the seasonal variation of plant water sources and response to precipitation in the desert-oasis ecotone of Linze, Northwestern China. We examined stable isotopic ratios of oxygen (δ18O) in stem water of desert shrubs as well as in precipitation, groundwater, and soil water in different soil layers and seasons to determine water sources for the shrubs. We found that the N. sibirica and H. ammodendron of 5-, 10-year old showed significant seasonal variation characteristics of δ18O value of stem water and water sources. However, the C. mongolicum and 20- and 40-year H. ammodendron main water sources were from deep soil water and groundwater, and less response to precipitation pulse. After 22.4 mm precipitation, the contribution of shallow soil water (0-50cm) to the use of N. sibirica increased from 6.7% to 36.5%; the C. mongolicum rarely use precipitation that were about 58.29% and 23.51%, absorbed from the deep soil water and groundwater; the contribution of precipitation to use of H. ammodendron had significantly differences among the four ages. The H. ammodendron of 5- and 10-year old about 86.3% and 42.5% water sources absorbed from the shallow soil water after precipitation. However, the contribution to 20- and 40-year old plant was less than 15%. So, the precipitation was one of the main water sources for desert shrubs, but the species showed different water utilization. We conclude that the main water source of the N. sibirica and H. ammodendron of 5-, 10-year was soil water recharged by precipitation, but the deeply rooted H. ammodendron of 20‐ and 40‐year‐old and the C. mongolicum have the ability to exploit a deep and reliable water source.

Keywords: water use pattern, water resource, stable isotope, seasonal change, precipitation pulse

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Authors: Morteza Malek Yarand, Hadi Saebi Monfared

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This study aimed at designing and developing a mechanical force gauge for the square watermelon mold for the first time. It also tried to introduce the square watermelon characteristics and its production limitations. The mechanical force gauge performance and the product itself were also described. There are three main designable gauge models: a. hydraulic gauge, b. strain gauge, and c. mechanical gauge. The advantage of the hydraulic model is that it instantly displays the pressure and thus the force exerted by the melon. However, considering the inability to measure forces at all directions, complicated development, high cost, possible hydraulic fluid leak into the fruit chamber and the possible influence of increased ambient temperature on the fluid pressure, the development of this gauge was overruled. The second choice was to calculate pressure using the direct force a strain gauge. The main advantage of these strain gauges over spring types is their high precision in measurements; but with regard to the lack of conformity of strain gauge working range with water melon growth, calculations were faced with problems. Finally the mechanical pressure gauge has advantages, including the ability to measured forces and pressures on the mold surface during melon growth; the ability to display the peak forces; the ability to produce melon growth graph thanks to its continuous force measurements; the conformity of its manufacturing materials with the required physical conditions of melon growth; high air conditioning capability; the ability to permit sunlight reaches the melon rind (no yellowish skin and quality loss); fast and straightforward calibration; no damages to the product during assembling and disassembling; visual check capability of the product within the mold; applicable to all growth environments (field, greenhouses, etc.); simple process; low costs and so forth.

Keywords: mechanical force gauge, mold, reshaped fruit, square watermelon

Procedia PDF Downloads 262

Authors: Sareh Rajabi, Taha Anjamrooz, Salwa Bheiry

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Sustainability of construction projects is an important issue to be addressed since the sector will continue to be developed in the coming years, especially in developing countries. Thus, it is significant to discover approaches and solutions for improving sustainability. Currently, the construction industry is the largest consumer of natural resources. This is the same in other countries in the Gulf region, and the United Arab Emirates (UAE) has limited natural resources such as water, electricity, etc. Recently, the UAE has taken several actions in order to implement sustainable initiatives within its construction industry. Within the industry, the contractors’ role is significant in promoting sustainable development by taking the responsibility to minimize their negative impacts on the environment and society, and maximize their economic distribution. In this research, sustainability will be studied as an important key to bring competitive advantages to contracting organizations. The contractors should understand the need to improve their sustainable performance in order to expand their business competitiveness. Competitiveness at the construction project level refers to a contractor’s ability to compete for a project. There is less focus on how to improve contractors’ competitiveness by implementing sustainable construction practices. Based on an inclusive literature review on the relationship between sustainability performance and business competitiveness, this research will conduct a study of sustainable practice in the construction industry and the relationship between sustainability performance and business competitiveness in order to develop a framework for evaluating how contractors can improve their competitiveness in terms of more efficient processes, enhancements in productivity, and lower costs of compliance in order to reduce the initial project cost and obtain market opportunities in the UAE. The research findings will provide a framework that can be a useful guideline for contractors to develop their sustainability policy, strategy and practice for meeting the increased requirements for sustainable development in construction.

Keywords: sustainable construction practice, sustainability, competitiveness, construction industry, contractors

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Authors: Keyvan Ramin

Abstract:

The geometric nonlinearity of Off-Diagonal Bracing System (ODBS) could be a complementary system to covering and extending the nonlinearity of reinforced concrete material. Finite element modeling is performed for flexural frame, x-braced frame and the ODBS braced frame system at the initial phase. Then the different models are investigated along various analyses. According to the experimental results of flexural and x-braced frame, the verification is done. Analytical assessments are performed in according to three-dimensional finite element modeling. Non-linear static analysis is considered to obtain performance level and seismic behavior, and then the response modification factors calculated from each model’s pushover curve. In the next phase, the evaluation of cracks observed in the finite element models, especially for RC members of all three systems is performed. The finite element assessment is performed on engendered cracks in ODBS braced frame for various time steps. The nonlinear dynamic time history analysis accomplished in different stories models for three records of Elcentro, Naghan, and Tabas earthquake accelerograms. Dynamic analysis is performed after scaling accelerogram on each type of flexural frame, x-braced frame and ODBS braced frame one by one. The base-point on RC frame is considered to investigate proportional displacement under each record. Hysteresis curves are assessed along continuing this study. The equivalent viscous damping for ODBS system is estimated in according to references. Results in each section show the ODBS system has an acceptable seismic behavior and their conclusions have been converged when the ODBS system is utilized in reinforced concrete frame.

Keywords: FEM, seismic behaviour, pushover analysis, geometric nonlinearity, time history analysis, equivalent viscous damping, passive control, crack investigation, hysteresis curve

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Authors: Kaisy Xinhong Ye, Su Lin Lim, Jialiang Li, Lei Feng

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background: Multiple healthful dietary patterns have been linked with dementia, but limited studies have looked at the role of diet in cognitive health in Asians whose eating habits are very different from their counterparts in the west. This study aimed to derive a dietary pattern that is associated with the risk of cognitive impairment (CI) in the Singaporean population. Method: The analysis was based on 719 community older adults aged 60 and above. Dietary intake was measured using a validated semi-quantitative food-frequency questionnaire (FFQ). Reduced rank regression (RRR) was used to extract dietary pattern from 45 food groups, specifying sugar, dietary fiber, vitamin A, calcium, and the ratio of polyunsaturated fat to saturated fat intake (P:S ratio) as response variables. The RRR-derived dietary patterns were subsequently investigated using multivariate logistic regression models to look for associations with the risk of CI. Results: A dietary pattern characterized by greater intakes of green leafy vegetables, red-orange vegetables, wholegrains, tofu, nuts, and lower intakes of biscuits, pastries, local sweets, coffee, poultry with skin, sugar added to beverages, malt beverages, roti, butter, and fast food was associated with reduced risk of CI [multivariable-adjusted OR comparing extreme quintiles, 0.29 (95% CI: 0.11, 0.77); P-trend =0.03]. This pattern was positively correlated with P:S ratio, vitamin A, and dietary fiber and negatively correlated with sugar. Conclusion: A dietary pattern providing high P:S ratio, vitamin A and dietary fiber, and a low level of sugar may reduce the risk of cognitive impairment in old age. The findings have significance in guiding local Singaporeans to dementia prevention through food-based dietary approaches.

Keywords: dementia, cognitive impairment, diet, nutrient, elderly

Procedia PDF Downloads 62

Authors: M. Dezyani, R. Ezzati bbelvirdi, M. Shakerian, H. Mirzaei

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Sodium Hexametaphosphate (SHMP) is commonly used as an Emulsifying Salt (ES) in process cheese, although rarely as the sole ES. It appears that no published studies exist on the effect of SHMP concentration on the properties of process cheese when pH is kept constant; pH is well known to affect process cheese functionality. The detailed interactions between the added phosphate, Casein (CN), and indigenous Ca phosphate are poorly understood. We studied the effect of the concentration of SHMP (0.25-2.75%) and holding time (0-20 min) on the textural and Rheological properties of pasteurized process Cheddar cheese using a central composite rotatable design. All cheeses were adjusted to pH 5.6. The meltability of process cheese (as indicated by the decrease in loss tangent parameter from small amplitude oscillatory rheology, degree of flow, and melt area from the Schreiber test) decreased with an increase in the concentration of SHMP. Holding time also led to a slight reduction in meltability. Hardness of process cheese increased as the concentration of SHMP increased. Acid-base titration curves indicated that the buffering peak at pH 4.8, which is attributable to residual colloidal Ca phosphate, was shifted to lower pH values with increasing concentration of SHMP. The insoluble Ca and total and insoluble P contents increased as concentration of SHMP increased. The proportion of insoluble P as a percentage of total (indigenous and added) P decreased with an increase in ES concentration because of some of the (added) SHMP formed soluble salts. The results of this study suggest that SHMP chelated the residual colloidal Ca phosphate content and dispersed CN; the newly formed Ca-phosphate complex remained trapped within the process cheese matrix, probably by cross-linking CN. Increasing the concentration of SHMP helped to improve fat emulsification and CN dispersion during cooking, both of which probably helped to reinforce the structure of process cheese.

Keywords: Iranian processed cheese, emulsifying salt, rheology, texture

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Authors: Abraham Addo-Bediako

Abstract:

Many freshwater ecosystems are facing immense pressure from anthropogenic activities, such as agricultural, industrial and mining. Trace metal pollution in freshwater ecosystems has become an issue of public health concern due to its toxicity and persistence in the environment. Trace elements pose a serious risk not only to the environment and aquatic biota but also humans. Chromium is one of such trace elements and its pollution in surface waters and groundwaters represents a serious environmental problem. In South Africa, agriculture, mining, industrial and domestic wastes are the main contributors to chromium discharge in rivers. The common forms of chromium are chromium (III) and chromium (VI). The latter is the most toxic because it can cause damage to human health. The aim of the study was to assess the contamination of chromium in the water and sediments of two rivers in the Steelpoort River sub-catchment of the Olifants River Basin, South Africa and human health risk. The concentration of Cr was analyzed using inductively coupled plasma–optical emission spectrometry (ICP-OES). The concentration of the metal was found to exceed the threshold limit, mainly in areas of high human activities. The hazard quotient through ingestion exposure did not exceed the threshold limit of 1 for adults and children and cancer risk for adults and children computed did not exceed the threshold limit of 10-4. Thus, there is no potential health risk from chromium through ingestion of drinking water for now. However, with increasing human activities, especially mining, the concentration could increase and become harmful to humans who depend on rivers for drinking water. It is recommended that proper management strategies should be taken to minimize the impact of chromium on the rivers and water from the rivers should properly be treated before domestic use.

Keywords: land use, health risk, metal pollution, water quality

Procedia PDF Downloads 66

Authors: Spyridon Komaitis, Christos Koutsarnakis, Evangelos Drosos, Aristotelis Kalyvas

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This study opts to investigate the intrinsic architecture, morphology, and spatial relationship of the subcortical pathways implicated in the connectivity of the motor/premotor cortex and SMA/pre-SMA complex. Twenty normal, adult, formalin-fixed cerebral hemispheres were explored through the fiber micro-dissection technique. Lateral to medial and medial to lateral dissections focused on the area of interest were performed in a tandem manner and under the surgical microscope. We traced the subcortical architecture, spatial relationships, and axonal connectivity of four major pathways: a) the dorsal component of the SLF (SLF-I) was found to reside in the medial aspect of the hemisphere and seen to connect the precuneus with the SMA and pre-SMA complex, b) the frontal longitudinal system (FLS) was consistently encountered as the natural anterior continuation of the SLF-II and SLF-III and connected the premotor and prefrontal cortices c) the fronto-caudate tract (FCT), a fan-shaped tract, was documented to participate in connectivity of the prefrontal and premotor cortices to the head and body of the caudate nucleus and d) the cortico-tegmental tract(CTT) was invariably recorded to subserve the connectivity of the tegmental area with the fronto-parietal cortex. No hemispheric asymmetries were recorded for any of the implicated pathways. Sub-segmentation systems were also proposed for each of the aforementioned tracts. The structural connectivity and functional specialization of motor and premotor areas in the human brain remain vague to this day as most of the available evidence derives either from animal or tractographic studies. By using the fiber-microdissection technique as our main method of investigation, we provide sound structural evidence on the delicate anatomy of the related white matter pathways.

Keywords: neuroanatomy, premotor, motor, connectivity

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Authors: N. Ali, S. Nakayama, H. Yamaguchi, M. Nadeem

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Traffic congestion is a matter of prime concern in developing countries. This can be primarily attributed due to poor design practices and biased allocation of resources based on political will neglecting the technical feasibilities in infrastructure design. During the last decade, Lahore has expanded at an unprecedented rate as compared to surrounding cities due to more funding and resource allocation by the previous governments. As a result of this, people from surrounding cities and areas moved to the Lahore city for better opportunities and quality of life. This migration inflow inherited the city with an increased population yielding the inefficiency of the existing infrastructure to accommodate enhanced traffic demand. This leads to traffic congestion on major arterial roads of the city. In this simulation study, a major arterial road was selected to evaluate the performance of the five intersections by changing the geometry of the intersections or signal control type. Simulations were done in two software; Highway Capacity Software (HCS) and Synchro Studio and Sim Traffic Software. Some of the traffic management strategies that were employed include actuated-signal control, semi-actuated signal control, fixed-time signal control, and roundabout. The most feasible solution for each intersection in the above-mentioned traffic management techniques was selected with the least delay time (seconds) and improved Level of Service (LOS). The results showed that Jinnah Hospital Intersection and Akbar Chowk Intersection improved 92.97% and 92.67% in delay time reduction, respectively. These results can be used by traffic planners and policy makers for decision making for the expansion of these intersections keeping in mind the traffic demand in future years.

Keywords: traffic congestion, traffic simulation, traffic management, congestion problems

Procedia PDF Downloads 457

Authors: Nesreddine Djafar Henni, Akram Khelaifia, Salah Guettala, Rachid Chebili

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Reinforced concrete shear walls and vertical plate-like elements play a pivotal role in efficiently managing a building's response to seismic forces. This study investigates how the performance of reinforced concrete buildings equipped with shear walls featuring different shear wall-to-frame stiffness ratios aligns with the requirements stipulated in the Algerian seismic code RPA99v2003, particularly in high-seismicity regions. Seven distinct 3D finite element models are developed and evaluated through nonlinear static analysis. Engineering Demand Parameters (EDPs) such as lateral displacement, inter-story drift ratio, shear force, and bending moment along the building height are analyzed. The findings reveal two predominant categories of induced responses: force-based and displacement-based EDPs. Furthermore, as the shear wall-to-frame ratio increases, there is a concurrent increase in force-based EDPs and a decrease in displacement-based ones. Examining the distribution of shear walls from both force and displacement perspectives, model G with the highest stiffness ratio, concentrating stiffness at the building's center, intensifies induced forces. This configuration necessitates additional reinforcements, leading to a conservative design approach. Conversely, model C, with the lowest stiffness ratio, distributes stiffness towards the periphery, resulting in minimized induced shear forces and bending moments, representing an optimal scenario with maximal performance and minimal strength requirements.

Keywords: dual RC buildings, RC shear walls, modeling, static nonlinear pushover analysis, optimization, seismic performance

Procedia PDF Downloads 41

Authors: E. Faizan, Wahab Abdul Ghafar, Tao Zhong

Abstract:

Steel plate shear walls (SPSWs) are a robust lateral load resistance structure because of their high flexibility and efficient energy dissipation when subjected to seismic loads. This research investigates the seismic performance of an innovative infill web strip (IWS-SPSW) and a typical unstiffened steel plate shear wall (USPSW). As a result, two 1:3 scale specimens of an IWS-SPSW and USPSW with a single story and a single bay were built and subjected to a cyclic lateral loading methodology. In the prototype, the beam-to-column connections were accomplished with the assistance of semi-rigid end-plate connectors. IWS-SPSW demonstrated exceptional ductility and shear load-bearing capacity during the testing process, with no cracks or other damage occurring. In addition, the IWS-SPSW could effectively dissipate energy without causing a significant amount of beam-column connection distortion. The shear load-bearing capacity of the USPSW was exceptional. However, it exhibited low ductility, severe infill plate corner ripping, and huge infill web plate cracks. The FE models were created and then confirmed using the experimental data. It has been demonstrated that the infill web strips of an SPSW system can affect the system's high performance and total energy dissipation. In addition, a parametric analysis was carried out to evaluate the material qualities of the IWS, which can considerably improve the system's seismic performances. These properties include the steel's strength as well as its thickness.

Keywords: steel shear walls, seismic performance, failure mode, hysteresis response, nonlinear finite element analysis, parametric study

Procedia PDF Downloads 63

Authors: Angel Liduvino Vara-Vela, Dirceu Luis Herdies, Debora Souza Alvim, Eder Paulo Vendrasco, Silvio Nilo Figueroa, Jayant Pendharkar, Julio Pablo Reyes Fernandez

Abstract:

Biomass-burning episodes are quite common in the central Amazon rainforest and represent a dominant source of aerosols during the dry season, between August and October. The increase in the occurrence of fires in 2019 in the world’s largest biomes has captured the attention of the international community. In particular, a rare and extreme smoke-related event occurred in the afternoon of Monday, August 19, 2019, in the most populous city in the Western Hemisphere, the São Paulo Metropolitan Area (SPMA), located in southeastern Brazil. The sky over the SPMA suddenly blackened, with the day turning into night, as reported by several news media around the world. In order to clarify whether or not the smoke that plunged the SPMA into sudden darkness was related to wildfires in the Amazon rainforest region, a set of 48-hour simulations over South America were performed using the Weather Research and Forecasting with Chemistry (WRF-Chem) model at 20 km horizontal resolution, on a daily basis, during the period from August 16 to August 19, 2019. The model results were satisfactorily compared against satellite-based data products and in situ measurements collected from air quality monitoring sites. Although a very strong smoke transport coming from the Amazon rainforest was observed in the middle of the afternoon on August 19, its impact on air quality over the SPMA took place in upper levels far above the surface, where, conversely, low air pollutant concentrations were observed.

Keywords: Amazon rainforest, biomass burning aerosols, São Paulo metropolitan area, WRF-Chem model

Procedia PDF Downloads 125