Search results for: compression ratio

Authors: Lukasz Kurowski, Paweł Smaga

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We explore the procyclicality of monetary policy decisions towards the financial cycle in the 1995−2015 period on a sample of six central banks. Using interest rate paths and the credit-to-GDP gap to construct a monetary policy procyclicality ratio, we provide evidence that monetary policy procyclicality was high in BoE and CNB and low in Riksbank and ECB. The results support the need for coordination between macroprudential and monetary policies, for example, by including financial stability considerations to the inflation targeting strategy.

Keywords: central bank, financial stability, macroprudential policy, monetary policy

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Authors: Larbi Belagraa, Miloud Beddar, Abderrazak Bouzid

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The needs of the construction sector still increasing for concrete. However, the shortage of natural resources of aggregate could be a problem for the concrete industry, in addition to the negative impact on the environment due to the demolition wastes. Recycling aggregate from construction and demolition (C&D) waste presents a major interest for users and researchers of concrete since this constituent can occupies more than 70% of concrete volume. The aim of the study here in is to assess the effect of sulfate resistant cement combined with the local mineral addition of marble waste fillers on the mechanical behavior of a recycled aggregate concrete (RAC). Physical and mechanical properties of RAC including the density, the flexural and the compressive strength were studied. The non destructive test methods (pulse-velocity, rebound hammer) were performed . The results obtained were compared to crushed aggregate concrete (CAC) using the normal compressive testing machine test method. The optimal content of 5% marble fillers showed an improvement for both used test methods (compression, flexion and NDT). Non-destructive methods (ultrasonic and rebound hammer test) can be used to assess the strength of RAC, but a correction coefficient is required to obtain a similar value to the compressive strength given by the compression tests. The study emphasizes that these waste materials can be successfully and economically utilized as additional inert filler in RAC formulation within similar performances compared to a conventional concrete.

Keywords: marble waste fillers, mechanical strength, natural aggregate, non-destructive testing (NDT), recycled aggregate concrete

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Authors: Annapurna Basavaraju, Arianna Mastrodonato, Franz Heitmeir

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The Advisory Council for Aeronautics Research in Europe (ACARE) is creating awareness for the overall reduction of NOx emissions by 80% in its vision 2020. Hence this promotes the researchers to work on novel technologies, one such technology is the use of alternative fuels. Among these fuels hydrogen is of interest due to its one and only significant pollutant NOx. The influence of NOx formation due to hydrogen combustion depends on various parameters such as air pressure, inlet air temperature, air to fuel jet momentum ratio etc. Appropriately, this research is motivated to investigate the impact of the air to fuel jet momentum ratio onto the NOx formation in a hydrogen combustion chamber for aircraft engines. The air to jet fuel momentum is defined as the ratio of impulse/momentum of air with respect to the momentum of fuel. The experiments were performed in an existing combustion chamber that has been previously tested for methane. Premix of the reactants has not been considered due to the high reactivity of the hydrogen and high risk of a flashback. In order to create a less rich zone of reaction at the burner and to decrease the emissions, a forced internal recirculation flow has been achieved by integrating a plate similar to honeycomb structure, suitable to the geometry of the liner. The liner has been provided with an external cooling system to avoid the increase of local temperatures and in turn the reaction rate of the NOx formation. The injected air has been preheated to aim at so called flameless combustion. The air to fuel jet momentum ratio has been inspected by changing the area of fuel inlets and keeping the number of fuel inlets constant in order to alter the fuel jet momentum, thus maintaining the homogeneity of the flow. Within this analysis, promising results for a flameless combustion have been achieved. For a constant number of fuel inlets, it was seen that the reduction of the fuel inlet diameter resulted in decrease of air to fuel jet momentum ratio in turn lowering the NOx emissions.

Keywords: combustion chamber, hydrogen, jet momentum, NOx emission

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Authors: W. H. El Garaihy, A. Nassef, S. Samy

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Equal channel angular pressing (ECAP) of commercial Al-Mg-Si alloy was conducted using two strain rates. The ECAP processing was conducted at room temperature and at 250 °C. Route A was adopted up to a total number of four passes in the present work. Structural evolution of the aluminum alloy discs was investigated before and after ECAP processing using optical microscopy (OM). Following ECAP, simple compression tests and Vicker’s hardness were performed. OM micrographs showed that, the average grain size of the as-received Al-Mg-Si disc tends to be larger than the size of the ECAP processed discs. Moreover, significant difference in the grain morphologies of the as-received and processed discs was observed. Intensity of deformation was observed via the alignment of the Al-Mg-Si consolidated particles (grains) in the direction of shear, which increased with increasing the number of passes via ECAP. Increasing the number of passes up to 4 resulted in increasing the grains aspect ratio up to ~5. It was found that the pressing temperature has a significant influence on the microstructure, Hv-values, and compressive strength of the processed discs. Hardness measurements demonstrated that 1-pass resulted in increase of Hv-value by 42% compared to that of the as-received alloy. 4-passes of ECAP processing resulted in additional increase in the Hv-value. A similar trend was observed for the yield and compressive strength. Experimental data of the Hv-values demonstrated that there is a lack of any significant dependence on the processing strain rate.

Keywords: Al-Mg-Si alloy, equal channel angular pressing, grain refinement, severe plastic deformation

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Authors: Bao Thach Nguyen, Abbas Mohajerani

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The California bearing ratio (CBR) has been acknowledged as an important parameter to characterize the bearing capacity of earth structures, such as earth dams, road embankments, airport runways, bridge abutments, and pavements. Technically, the CBR test can be carried out in the laboratory or in the field. The CBR test is time-consuming and is infrequently performed due to the equipment needed and the fact that the field moisture content keeps changing over time. Over the years, many correlations have been developed for the prediction of CBR by various researchers, including the dynamic cone penetrometer, undrained shear strength, and Clegg impact hammer. This paper reports and discusses some of the results from a study on the prediction of CBR. In the current study, the CBR test was performed in the laboratory on some fine-grained subgrade soils collected from various locations in Victoria. Based on the test results, a satisfactory empirical correlation was found between the CBR and the physical properties of the experimental soils.

Keywords: California bearing ratio, fine-grained soils, soil physical properties, pavement, soil test

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Authors: Kamrun N. Keya, Nasrin A. Kona, Ruhul A. Khan

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Bamboo fiber (BF) reinforced polypropylene (PP) based composites were fabricated by a conventional compression molding technique. In this investigation, bamboo composites were manufactured using different percentages of fiber, which were varying from 25-65% on the total weight of the composites. To fabricate the BF/PP composites untreated and treated fibers were selected. A systematic study was done to observe the physical, mechanical, and interfacial behavior of the composites. In this study, mechanical properties of the composites such as tensile, impact, and bending properties were observed precisely. Maximum tensile strength (TS) and bending strength (BS) were found for 50 wt% fiber composites, 65 MPa, and 85.5 MPa respectively, whereas the highest tensile modulus (TM) and bending modulus (BM) was examined, 5.73 GPa and 7.85 GPa respectively. The BF/PP based composites were treated with irradiated under gamma radiation (the source strength 50 kCi Cobalt-60) of various doses (i.e. 10, 20, 30, 40, 50 and 60 kGy doses). The effect of gamma radiation on the composites was also investigated, and it found that the effect of 30.0 kGy (i.e. units for radiation measurement is 'gray', kGy=kilogray) gamma dose showed better mechanical properties than other doses. After flexural testing, fracture sides of the untreated and treated both composites were studied by scanning electron microscope (SEM). SEM results of the treated BF/PP based composites showed better fiber-matrix adhesion and interfacial bonding than untreated BF/PP based composites. Water uptake and soil degradation tests of untreated and treated composites were also investigated.

Keywords: bamboo fiber, polypropylene, compression molding technique, gamma radiation, mechanical properties, scanning electron microscope

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Authors: T. Nishimura, K. Doi, H. Fujimoto, T. Wada

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The Number of people with acquired visual impairments has increased in recent years. In specialized courses at schools for the blind and in Braille lessons offered by social welfare organizations, many people with acquired visual impairments cannot learn to read adequately Braille. One of the reasons is that the common Braille patterns for people visual impairments who already has mature Braille reading skill being difficult to read for Braille reading beginners. In addition, there is the scanty knowledge of Braille book manufacturing companies regarding what Braille patterns would be easy to read for beginners. Therefore, it is required to investigate a suitable Braille patterns would be easy to read for beginners. In order to obtain knowledge regarding suitable Braille patterns for beginners, this study aimed to elucidate the relationship between readability of paper-based Braille and its patterns. This study focused on character spacing, which readily affects Braille reading ability, to determine a suitable character spacing ratio (ratio of character spacing to dot spacing) for beginners. Specifically, considering beginners with acquired visual impairments who are unfamiliar with reading Braille, we quantitatively evaluated the effect of character spacing ratio on Braille readability through an evaluation experiment using sighted subjects with no experience of reading Braille. In this experiment, ten sighted adults took the blindfold were asked to read test piece (three Braille characters). Braille used as test piece was composed of five dots. They were asked to touch the Braille by sliding their forefinger on the test piece immediately after the test examiner gave a signal to start the experiment. Then, they were required to release their forefinger from the test piece when they perceived the Braille characters. Seven conditions depended on character spacing ratio was held (i.e., 1.2, 1.4, 1.5, 1.6, 1.8, 2.0, 2.2 [mm]), and the other four depended on the dot spacing (i.e., 2.0, 2.5, 3.0, 3.5 [mm]). Ten trials were conducted for each conditions. The test pieces are created using by NISE Graphic could print Braille adjusted arbitrary value of character spacing and dot spacing with high accuracy. We adopted the evaluation indices for correct rate, reading time, and subjective readability to investigate how the character spacing ratio affects Braille readability. The results showed that Braille reading beginners could read Braille accurately and quickly, when character spacing ratio is more than 1.8 and dot spacing is more than 3.0 mm. Furthermore, it is difficult to read Braille accurately and quickly for beginners, when both character spacing and dot spacing are small. For this study, suitable character spacing ratio to make reading easy for Braille beginners is revealed.

Keywords: Braille, character spacing, people with visual impairments, readability

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Authors: M. Khalid Alamgir, Javed Ahsan Bhatti, M. Zafarullah Khan

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Thin film of amorphous carbon (DLC) was deposited on 316 steel using Nd: YAG laser having energy 300mJ. Pure graphite was used as a target. The vacuum in the deposition chamber was generated in the range of 10-6 mbar by turbo molecular pump. Ratio of sp3 to sp2 content shows amorphous nature of the film. This was confirmed by Raman spectra having two peaks around 1300 cm-1 i.e. D-band to 1700 cm-1 i.e. G-band. If sp3 bonding ratio is high, the films behave like diamond-like whereas, with high sp2, films are graphite-like. The ratio of sp3 and sp2 contents in the film depends upon the deposition method, hydrogen contents and system parameters. The structural study of the film was carried out by XRD. The hardness of the films as measured by Vickers hardness tester and was found to be 28 GPa. The EDX result shows the presence of carbon contents on the surface in high rate and optical microscopy result shows the smoothness of the film on substrate. The film possesses good adhesion and can be used to coat surgical instruments.

Keywords: DLC, thin film, Raman spectroscopy, XRD, EDX

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Authors: Shinji Ukita, Naohiro Nakamura, Yuji Miyazu

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In considering the dynamic characteristics of structure, natural frequency and damping ratio are useful indicator. When performing dynamic design, it's necessary to select an appropriate initial damping model and hysteretic model. In the linear region, the setting of initial damping model influences the response, and in the nonlinear region, the combination of initial damping model and hysteretic model influences the response. However, the dynamic characteristics of structure in the nonlinear region remain unclear. In this paper, we studied the effect of setting of initial damping model and hysteretic model on the dynamic characteristics of structure. On initial damping model setting, Initial stiffness proportional, Tangent stiffness proportional, and Rayleigh-type were used. On hysteretic model setting, TAKEDA model and Normal-trilinear model were used. As a study method, dynamic analysis was performed using a lumped mass model of base-fixed. During analysis, the maximum acceleration of input earthquake motion was gradually increased from 1 to 600 gal. The dynamic characteristics were calculated using the ARX model. Then, the characteristics of 1st and 2nd natural frequency and 1st damping ratio were evaluated. Input earthquake motion was simulated wave that the Building Center of Japan has published. On the building model, an RC building with 30×30m planes on each floor was assumed. The story height was 3m and the maximum height was 18m. Unit weight for each floor was 1.0t/m2. The building natural period was set to 0.36sec, and the initial stiffness of each floor was calculated by assuming the 1st mode to be an inverted triangle. First, we investigated the difference of the dynamic characteristics depending on the difference of initial damping model setting. With the increase in the maximum acceleration of the input earthquake motions, the 1st and 2nd natural frequency decreased, and the 1st damping ratio increased. Then, in the natural frequency, the difference due to initial damping model setting was small, but in the damping ratio, a significant difference was observed (Initial stiffness proportional≒Rayleigh type>Tangent stiffness proportional). The acceleration and the displacement of the earthquake response were largest in the tangent stiffness proportional. In the range where the acceleration response increased, the damping ratio was constant. In the range where the acceleration response was constant, the damping ratio increased. Next, we investigated the difference of the dynamic characteristics depending on the difference of hysteretic model setting. With the increase in the maximum acceleration of the input earthquake motions, the natural frequency decreased in TAKEDA model, but in Normal-trilinear model, the natural frequency didn’t change. The damping ratio in TAKEDA model was higher than that in Normal-trilinear model, although, both in TAKEDA model and Normal-trilinear model, the damping ratio increased. In conclusion, in initial damping model setting, the tangent stiffness proportional was evaluated the most. In the hysteretic model setting, TAKEDA model was more appreciated than the Normal-trilinear model in the nonlinear region. Our results would provide useful indicator on dynamic design.

Keywords: initial damping model, damping ratio, dynamic analysis, hysteretic model, natural frequency

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Authors: Imad Zeyad Ramadan

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In this paper a genetic algorithm was developed to construct the optimal portfolio based on the Treynor method. The GA maximizes the Treynor ratio under budget constraint to select the best allocation of the budget for the companies in the portfolio. The results show that the GA was able to construct a conservative portfolio which includes companies from the three sectors. This indicates that the GA reduced the risk on the investor as it choose some companies with positive risks (goes with the market) and some with negative risks (goes against the market).

Keywords: oOptimization, genetic algorithm, portfolio selection, Treynor method

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Authors: Omid Gholipoor Bashiri, Ghafur Mosavi, Aliasghar Behnamghader, Seyed Mahmood Rabiee

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Objective: To determine the effect of selected bone graft on the compression properties of radial bone in rabbit. Design-Experimental in vivo study. Animals: A total of 45 adult male New Zealand white rabbits. Procedures: The rabbits were anesthetized and a one-cm-full thickness piece of radial bone was removed using oscillating saw in the all rabbit. The rabbits were divided into 5 groups on the basis of the material used to fill the bone defect: group 1: the paste of bone cement calcium phosphate; group II: the paste of calcium phosphate mixture with type I collagen; group III: tricalcium phosphate mixed with hydroxyapatite (TCP & HP) with 5% porosity; group IV: the same scaffold as group III with 10% porosity; and group V: the same scaffold as group III and IV with 20% porosity, with 9 rabbits in each group. Subsequently subdivided into 3 subgroups of 3 rabbits each. Results: There was a significant increase in compression properties of radial bone in the group II and V in 2nd and 3rd months as compared with groups I, III and IV. The mean endurable crack-strength in group II and V were slightly higher than that of normal radius (P<0.05). Conclusion and clinical relevance: Application of calcium phosphate paste with type I collagen and scaffold of tricalcium phosphate with hydroxyapatite having 20% porosity indicated to have positive effect in integral formation of qualitative callus at the site of fracture and early re-organization of callus to regain mechanical strength too.

Keywords: calcium phosphate, tricalcium phosphate, hydroxyapatite, radial bone, compressive properties, porosity, type i collagen, rabbit

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Authors: Vinod K. Singh, S. G. Chung

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The degree of structuration of Busan clays at the mouth of Nakdong River mouth was highly influenced by the depositional environment, i.e., flow of the river stream, marine regression, and transgression during the sedimentation process. As a result, the geotechnical properties also varies along the depth with change in degree of structuration. Thus, the in-situ tests such as cone penetration test (CPT) could not be used to predict various geotechnical properties properly by using the conventional empirical methods. In this paper, the shear wave velocity (Vs) was measured from the field using the seismic dilatometer. The Vs was also measured in the laboratory from high quality undisturbed and remolded samples using bender element method to evaluate the degree of structuration. The degree of structuration was quantitatively defined by the modulus ratio of undisturbed to remolded soil samples which is found well correlated with the normalized void ratio (e0/eL) where eL is the void ratio at the liquid limit. It is revealed that the empirical method based on laboratory results incorporating e0/eL can predict Vs from the field more accurately. Thereafter, the CPT based empirical method was developed to estimate the shear wave velocity taking the effect of structuration in the consideration. The developed method was found to predict shear wave velocity reasonably for Busan clays.

Keywords: level of structuration, normalized modulus, normalized void ratio, shear wave velocity, site characterization

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Authors: Aayushi Pandey, Manoj Kumar Pandey, Ashutosh Tiwari, Kireet Kumar

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Glaciers play an important role in climate change and are sensitive phenomena of global climate change scenario. Glaciers in Himalayas are unique as they are predominantly valley type and are located in tropical, high altitude regions. These glaciers are often covered with debris which greatly affects ablation rate of glaciers and work as a sensitive indicator of glacier health. The aim of this study is to map high altitude Glacier surface with a focus on glacial lake and debris estimation using different techniques in Nagling glacier of dhauliganga basin in Himalayan region. Different Image Classification techniques i.e. thresholding on different band ratios and supervised classification using maximum likelihood classifier (MLC) have been used on high resolution sentinel 2A level 1c satellite imagery of 14 October 2017.Here Near Infrared (NIR)/Shortwave Infrared (SWIR) ratio image was used to extract the glaciated classes (Snow, Ice, Ice Mixed Debris) from other non-glaciated terrain classes. SWIR/BLUE Ratio Image was used to map valley rock and Debris while Green/NIR ratio image was found most suitable for mapping Glacial Lake. Accuracy assessment was performed using high resolution (3 meters) Planetscope Imagery using 60 stratified random points. The overall accuracy of MLC was 85 % while the accuracy of Band Ratios was 96.66 %. According to Band Ratio technique total areal extent of glaciated classes (Snow, Ice ,IMD) in Nagling glacier was 10.70 km2 nearly 38.07% of study area comprising of 30.87 % Snow covered area, 3.93% Ice and 3.27 % IMD covered area. Non-glaciated classes (vegetation, glacial lake, debris and valley rock) covered 61.93 % of the total area out of which valley rock is dominant with 33.83% coverage followed by debris covering 27.7 % of the area in nagling glacier. Glacial lake and Debris were accurately mapped using Band ratio technique Hence, Band Ratio approach appears to be useful for the mapping of debris covered glacier in Himalayan Region.

Keywords: band ratio, Dhauliganga basin, glacier mapping, Himalayan region, maximum likelihood classifier (MLC), Sentinel-2 satellite image

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Authors: Jeonghun Nam, Seonggil Kim, Hyunjoo Choi, Chae Seung Lim

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Quantification and analysis of rare cells are challenging in clinical applications and cell biology due to its extremely small number in blood. In this work, we propose a viscoelastic microfluidic device for continuous cell concentration without sheath flows. Due to the viscoelastic effect on suspending cells, cells with the blockage ratio higher than 0.1 could be tightly focused at the center of the microchannel. The blockage ratio was defined as the particle diameter divided by the channel width. Finally, cells were concentrated through the center outlet and the additional suspending medium was removed to the side outlets. Since viscoelastic focusing is insensitive to the flow rate higher than 10 μl/min, the non-powered hand pump sprayer could be used with no accurate control of the flow rate, which is suitable for clinical settings in resource-limited developing countries. Using multiple concentration processes, high-throughput concentration of white blood cells in lysed blood sample was achieved by ~ 300-fold.

Keywords: cell concentration, high-throughput, non-powered, viscoelastic fluid

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Authors: S. A. Naeini, Z. Eftekhari

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Liquefaction phenomenon in sand is nowadays a classical soil mechanics subject. Using a cyclic triaxial test apparatus, we use non-woven geotextile reinforcement to improve the liquefaction resistance of sand. The layer configurations used are zero, one, two and three horizontal reinforcing layers in a triaxial test sample. The influences of the number of geotextile layers, and cyclic stress ratio (CSR) were studied and described. The results illustrated that the geotextile inclusion increases liquefaction resistance.

Keywords: liquefaction resistance, geotextile, sand, cyclic triaxial test, cyclic stress ratio

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Authors: Akanle Florence Foluso

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This paper examined briefly the patriarchy nature of gendered power system: a network of social, political and economic relationships through which men dominate and control female labour, as well as define women’s status, privileges and rights in the society. The paper discusses the historical perspective of “the academic experience of women. It takes a look at the plight of women in a academia in some Nigeria. Universities in at present to see if both men and women have equal opportunities. This paper focuses on women in Academics today, it examines the overall gender proportions of men and women by universities, women/men ratios by lecturers, women and men ratio of associate professors, women and men ratio of professors by universities. It also examines women and men ratio by Dean also executive heads (Vice Chancellors) Expofactor design was be used. The study population comprised of three selected universities from Ondo, Ekiti and Zanfara respectively. Involuntary and indept interview was used to collect data for the study data for the study was also collected from so purposively selected academic staff in the categories of Dean and senior staff who are familiar with gender issues. Findings souls that there is gender inequality academia.

Keywords: women, gender, inequality, academia

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Authors: Lale Efe, Zeynep Gokce

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In this study carried out in 2013-14 growing season in East Mediterranean Region of Turkey, it was aimed to investigate the effects of different sowing times on the seed yield and quality of fenugreek (Trigonella foenum graceum L.). Three fenugreek genotypes (Gürarslan, Candidate Line-1 and Genotype-1) were sown on 13.11.2013 and 07.03.2014 according to factorial randomized block design with 3 replications. Plant height (cm), branch number per plant, first pod height (cm), pod length (mm), seed number per pod (g), seed yield per plant (g), seed yield per decar (kg), thousand seed weight (g), mucilage rate (%), seed protein ratio (%), seed oil ratio (%), oleic acid (%), linoleic acid (%), palmitic acid (%) and stearic acid (%) were investigated. Among genotypes, while the highest seed yield per plant was obtained from Genotype-1 (5 g/plant), the lowest seed yield per plant was obtained from cv. Gürarslan (3.4 g/plant). According to genotype x sowing date interactions, it can be said that the highest seed yield per plant was taken in autumn sowing from Genotype-1 (6.6 g/plant) and the lowest seed yield per plant was taken in spring sowing from cv. Gürarslan (2.9 g/plant). Genotype-1 had the highest linoleic acid ratio (41.6 %). Cv. Gürarslan and Candidate Line-1 had the highest oleic acid ratio (respectively 17.8 % and 17.6%).

Keywords: fenugreek, seed yield and quality, sowing times, Trigonella foenum graecum L.

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Authors: Yusuf Yılmaz, Kevser Dincer, Derya Saygılı

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In this study, performance of PEMs was experimentally investigated. Coating on the cathode side of the PEMs fuel cells was accomplished with the spray method by using NaCaNiBO. A solution having 0,1 gr NaCaNiBO +10 mL methanol was prepared. This solution was taken out and filled into a spray. Then the cathode side of PEMs fuel cells was cladded with NaCaNiBO by using spray method. After coating, the membrane was left out to dry for 24 hours. The PEM fuel cells were mounted to the system in single, double, triple and fourfold manner in order to spot the best performance. The performance parameter considered was the power to current ratio. The best performance was found to occur at the 300th second with the power/current ratio of 3.55 Watt/Ampere and on the fourfold parallel mounting after the coating; whereas the poorest performance took place at the 210th second, power to current ratio of 0.12 Watt/Ampere and on the twofold parallel connection after the coating.

Keywords: nano-composites, proton exchange membranes, performance improvement, fuel cell

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Authors: Kyong-Ku Yun, Kyeo-Re Lee, Kyong Namkung, Seung-Yeon Han, Pan-Gil Choi

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Sprayed concrete is a way to spray a concrete using a machinery with high air pressure. There are insufficient studies on the durability and early-age behavior of sprayed concrete using high quality expansion agent. A series of an experiment were executed with 5 varying expansion agent replacement rates, while all the other conditions were kept constant, including cement binder content and water-cement ratio. The tests includes early-age shrinkage test, rapid chloride permeability test, and image analysis of air void structure. The early-age expansion test with the variation of expansion agent show that the expansion strain increases as the ratio of expansion agent increases. The rapid chloride permeability test shows that it decrease as the expansion agent increase. Therefore, expansion agent affects into the rapid chloride permeability in a better way. As expansion agent content increased, spacing factor slightly decreased while specific surface kept relatively stable. As a results, the optimum ratio of expansion agent would be selected between 7 % and 11%.

Keywords: sprayed concrete, durability, early-age behavior, expansion admixture

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Authors: Fryanto Anugrah Rhamdhani Rhamdhani, Hana Riana Permatasari

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The aim of this study analyzes the inclusive of economic growth and analyzes the inclusive of economic growth determinant in regency and city (West Java Province). The background this study Economic Growth can do not afford to reduce poverty, Disparity and expand The Workforce. Referring Central Bureau Of Statistic West Java Province report in 2015 recorded only 5 regions able reduce poverty, 3 regions able reduce Gini Ratio and 7 regions able Workforce Absorption, meanwhile, 11 regions was improved Economic Growth. The Inclusive of Economic Growth definition based on various literature means the quality Economic Growth able reduce Poverty, Gini Ratio, and Workforce absorption. This study adopted the measurement Inclusive Economic of Growth Klassen and analyzes factor in Term Reducing Poverty, Gini Ratio, and the workforce Absorption. Data used panels data composite time series and cross-section including 25 regency and cities regions from Central Bureau Of Statistic West Java Province during 2014-2015. As a result, the measurement inclusive economic of growth Klassen 2014-2015 from 25 regency and cities shows all region does not inclusive reducing Poverty, only 2 regions able reduce Gini Ratio and 3 regions able increase Workforce absorption. Different from the result the measurement Inclusive Economic of Growth for workforce absorption, several regions shows a negative coefficient indicates Economic Growth decline Workforce absorption. The outcome of this study analyzes factor of Inclusive economic of Growth, so that give recommendations for government achieve inclusive economic of growth toward Sustainable Economic. Can be Concluded above low-quality Economic Growth, that due to all region does not inclusive Economic of Growth.

Keywords: inclusive economic growth, Gini ratio, poverty, workforce

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Authors: Mostafa Amirjan

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In the present study, the properties of Al-Al2O3 nanocomposite hollow sphere structures were investigated. For this reason, the Al-based nanocomposite hollow spheres with different amounts of nano alumina reinforcement (0-10wt %) and different ratio of thickness to diameter (t/D: 0.06-0.3) were prepared via a powder metallurgy method. Then, the effect of mentioned parameters was studied on physical and quasi static mechanical properties of their related prepared structures (open/closed cell) such as density, hardness, strength and energy absorption. It was found that as the t/D ratio increases the relative density, compressive strength and energy absorption increase. The highest values of strength and energy absorption were obtained from the specimen with 5 wt. % of nanoparticle reinforcement, t/D of 0.3 (t=1 mm, D=400µm) as 22.88 MPa and 13.24 MJ/m3, respectively. The moderate specific strength of prepared composites in the present study showed the good consistency with the properties of others low carbon steel composite with similar structure.

Keywords: hollow sphere structure foam, nanocomposite, thickness and diameter (t/D ), powder metallurgy

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Authors: Sewon Kim, Changyeop Lee

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A noble low NOx combustion technology, based on partial oxidation combustion concept in a fuel rich combustion zone, is successfully applied in this research. The burner is designed such that a portion of fuel is heated and pre-vaporized in the furnace then injected into a fuel rich combustion zone so that a partial oxidation reaction occurs. The effects of equivalence ratio, thermal load, and fuel distribution ratio on the emissions of NOx and CO are experimentally investigated. This newly developed combustion technology is successfully applied to industrial furnace, and showed extremely low NOx emission levels.

Keywords: low NOx, combustion, burner, fuel rich

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Authors: Mohammad Mahdi Kioumarsi

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In this paper, using the response surface method (RSM), tornado diagram method and non-linear finite element analysis, the effect of four parameters on residual bending capacity of a corroded RC beam was investigated. The parameters considered are amount of localised cross section reduction, ratio of pit distance on adjacent bars to rebar distance, concrete compressive strength, and rebar tensile strength. The focus is on the influence on the bending ultimate limit state. Based on the obtained results, the effects of the ratio of pit distance to rebar distance (Lp⁄Lr) and the ratio of the localised cross section reduction to the original area of the rebar (Apit⁄A0) were found significant. The interference of localised corrosion on adjacent reinforcement bars reduces the bending capacity of under-reinforced concrete beam. Using the sensitivity analysis could lead to recognize uncertainty parameters, which have the most influences on the performance of the structure.

Keywords: localised corrosion, concrete beam, sensitivity analyses, ultimate capacity

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Authors: Bahareh Najafian Ashrafi, Hossein Zeidabadinejad, Mehdi Ashjaee

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The temperature field is a key factor of flame heat transfer rate and therefore should be measured accurately. In this study, the Mach-Zehnder Interferometry method is applied to measure the temperature field of premixed air/landfill gas (LFG60:60% CH4+40% CO2) laminar flame. The three-dimensional flame of cylindrical slot burner can assume to be two-dimensional due to the high aspect ratio (L/W=10) of the rectangular slot. So, the method converts two-dimensional flame to closed isothermal curves called fringes and the outer fringes temperature is measured by thermocouples. The experiments are carried out for Reynolds numbers and equivalence ratios ranging from 100 to 400 and 1.0 to 1.4, respectively. Results show that by increasing the equivalence ratio or Reynolds number, the flame height increases. The maximum flame temperature decreases by increasing the equivalence ratio but does not change considerably by changing the Reynolds number.

Keywords: landfill gas, Mach-Zehender interferometry, premix flame, slot burner, temperature filed

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Authors: Asmaa Al Shafiee, Erdin Ibraim

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Stabilizing slopes by using vegetation is considered as a cost-effective and eco-friendly alternative to the conventional methods. The main aim of this study is to investigate the mechanical effect of analogue root systems on the shear strength of different soil types. Three objectives were defined to achieve the main aim of this paper. Firstly, explore the effect of root architectural design to shear strength parameters. Secondly, study the effect of root area ratio (RAR) on the shear strength of two different soil types. Finally, to investigate how different kinds of soil can affect the behavior of the roots during shear failure. 3D printing tool was used to develop different analogue tap root models with different architectural designs. Direct shear tests were performed on Leighton Buzzard (LB) fraction B sand, which represents a coarse sand and Huston sand, which represent medium-coarse sand. All tests were done with the same relative density for both kinds of sand. The results of the direct shear test indicated that using plant roots will increase both friction angle and cohesion of soil. Additionally, different root designs affected differently the shear strength of the soil. Furthermore, the directly proportional relationship was found between root area ratio for the same root design and shear strength parameters of soil. Finally, the root area ratio effect should be combined with branches penetrating the shear plane to get the highest results.

Keywords: leighton buzzard sand, root area ratio, rooted soil, shear strength, slope stabilization

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Authors: Hossain A, Hossain S.

Abstract:

Introduction: In a small cohort, we sought to assess the magnetic resonance spectroscopy's (MRS) ability to predict the presence of metastatic lesions. Method: A Popular Diagnostic Centre Limited enrolled patients with neuroepithelial tumors. The 1H CSI MRS of the brain allows us to detect changes in the concentration of specific metabolites caused by metastatic lesions. Among these metabolites are N-acetyl-aspartate (NNA), creatine (Cr), and choline (Cho). For Cho, NAA, Cr, and Cr₂, the metabolic ratio was calculated using the division method. Results: The NAA values were 0.63 and 5.65 for tumor cells, 1.86 and 5.66 for normal cells, and 1.86 and 5.66 for normal cells 2. NAA values for normal cells 1 were 1.84, 10.6, and 1.86 for normal cells 2, respectively. Cho levels were as low as 0.8 and 10.53 in the tumor cell, compared to 1.12 and 2.7 in the normal cell 1 and 1.24 and 6.36 in the normal cell 2. Cho/Cr₂ barely distinguished itself from the other ratios in terms of significance. For tumor cells, the ratios of Cho/NAA, Cho/Cr₂, NAA/Cho, and NAA/Cr₂ were significant. Normal cell 1 had significant Cho/NAA, Cho/Cr, NAA/Cho, and NAA/Cr ratios. Conclusion: The clinical result can be improved by using 1H-MRSI to guide the size of resection for metastatic lesions. Even though it is non-invasive and doesn't present any difficulties during the procedure, MRS has been shown to predict the detection of metastatic lesions.

Keywords: metabolite ratio, MRI images, metastatic lesion, MR spectroscopy, N-acetyl-aspartate

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Authors: Ratna Dewi Kusumaningtyas, Prima Astuti Handayani, Arief Budiman

Abstract:

Reactive Distillation (RD) is a multifunctional reactor which integrates chemical reaction with in situ separation to shift the equilibrium towards the product formation. Thus, it is suitable for equilibrium limited reaction such as esterification and transesterification to enhance the reaction conversion. In this work, the application of RD for high FFA oil esterification-transterification for biodiesel production using sulphuric acid catalyst has been studied. Crude Jatropha Oil with FFA content of 30.57% was utilized as the feedstock. Effects of the catalyst concentration and molar ratio of the alcohol to oils were also investigated. It was revealed that best result was obtained with sulphuric acid catalyst (reaction conversion of 94.71% and FFA content of 1.62%) at 60C, molar ratio of methanol to FFA of 30:1, and catalyst loading of 3%. After undergoing esterification reaction, jatropha oil was then transesterified to produce biodiesel. Transesterification reaction was performed in the presence of NaOH catalyst in RD column at 60C, molar ratio of methanol to oil of 6:1, and catalyst concentration of 1%. It demonstrated that biodiesel produced in this work agreed with the Indonesian National and ASTM standard of fuel.

Keywords: reactive distillation, biodiesel, esterification, transesterification

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Authors: Saeedullah J. Mandokhail, Shamsher Sadiq, Meer H. Khan

Abstract:

This paper presents the comparison of excess pore water pressure ratio (ru) predicted by using accumulated stress based pore pressure model and plasticity model. One dimensional effective stress site response analyses were performed on a 30 m deep sand column (consists of a liquefiable layer in between non-liquefiable layers) using accumulated stress based pore pressure model in Deepsoil and PDMY2 (PressureDependentMultiYield02) model in Opensees. Three Input motions with different peak ground acceleration (PGA) levels of 0.357 g, 0.124 g, and 0.11 g were used in this study. The developed excess pore pressure ratio predicted by the above two models were compared and analyzed along the depth. The time history of the ru at mid of the liquefiable layer and non-liquefiable layer were also compared. The comparisons show that the two models predict mostly similar ru values. The predicted ru is also consistent with the PGA level of the input motions.

Keywords: effective stress, excess pore pressure ratio, pore pressure model, site response analysis

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Authors: S. S. L. Andrade, E. A. Souza, L. C. L. Santos, C. Moraes, A. K. C. L. Lobato

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Biodiesel production using membrane reactor has become increasingly studied, because this process minimizes some of the main problems encountered in the biodiesel purification. The membrane reactor tries to minimize post-treatment steps, resulting in cost savings and enabling the competitiveness of biodiesel produced by homogeneous alkaline catalysis. This is due to the reaction and product separation may occur simultaneously. In order to evaluate the production of biodiesel from soybean oils using a tubular membrane reactor, a factorial experimental design was conducted (2³) to evaluate the influence of following variables: temperature (45 to 60 °C), catalyst concentration (0.5 to 1% by weight) and molar ratio of oil/methanol (1/6 to 1/9). In addition, the parametric sensitivity was evaluated by the analysis of variance and model through the response surface. The results showed a tendency of influence of the variables in the reaction conversion. The significance effect was higher for the catalyst concentration followed by the molar ratio of oil/methanol and finally the temperature. The best result was obtained under the conditions of 1% catalyst (KOH), molar ratio oil/methanol of 1/9 and temperature of 60 °C, resulting in an ester content of 99.07%.

Keywords: biodiesel production, factorial design, membrane reactor, soybean oil

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Authors: Suddhasil Siddhanta, Debasish Nandy

Abstract:

Child sex ratios pattern in the Asian Population is highly masculine mainly due to birth masculinity and gender bias in child mortality. The vast and the growing literature of female deficit in world population points out the diffusion of child sex ratio pattern in many Asian as well as neighboring European countries. However, little attention has been given to understand the common factors in different demographics in explaining child sex ratio pattern. Such a scholarship is extremely important as level of gender inequity is different in different country set up. Our paper tries to explain the major structural commonalities in the child masculinity pattern in two demographic billionaires - India and China. The analysis reveals that apart from geographical diffusion of sex selection technology, patrilocal social structure, as proxied by households with more than one generation in China and proportion of population aged 65 years and above in India, can explain significant variation of missing girl child in these two countries. Even after controlling for individual capacity building factors like educational attainment, or work force participation, the measure of social stratification is coming out to be the major determinant of child sex ratio variation. Other socio economic factors that perform much well are the agency building factors of the females, like changing pattern of marriage customs which is proxied by divorce and remarriage ratio for china and percentage of female marrying at or after the age of 20 years in India and the female workforce participation. Proportion of minorities in socio-religious composition of the population and gender bias in scholastic attainment in both these counties are also found to be significant in modeling child sex ratio variations. All these significant common factors associated with child sex ratio point toward the one single most important factor: the historical evolution of patriarchy and its contemporary perpetuation in both the countries. It seems that prohibition of sex selection might not be sufficient to combat the peculiar skewness of excessive maleness in child population in both these countries. Demand sided policies is therefore utmost important to root out the gender bias in child sex ratios.

Keywords: child sex ratios, gender bias, structural factors, prosperity, patrilocality

Procedia PDF Downloads 157