Search results for: dual curing
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1089

Search results for: dual curing

639 Effect of Concentration of Alkaline and Curing Temperature on Compressive Strength of Geopolymer Concert

Authors: Nursah Kutuk, Sevil Cetinkaya

Abstract:

Geopolymers are becoming new concrete materials to use alongside cement, which are formed due to reaction between alumino-silicates and oxides with alkaline media. Silicates obtained from natural minerals or industrial wastes are used for geopolymer synthesis. Geopolymers have recently received wide attention because of their advantages over other cementitious material like Portland cement. Some of the advantages are high compressive strength, low environmental impact, chemical and fire resistance and thermal stability. In this study, geopolymers were prepared by using inorganic materials such as kaolinite and calcite. The experiments were carried out by varying the concentration of NaOH as 5, 10, 15 and 20 M, and at cure temperature of 22, 45 and 65 °C. Compressive strengths for each mixes at each cure temperature were measured. Results of the analyses indicated that the compressive strength of geopolymers did not increase steadily with increasing concentration of NaOH, but did increase steadily with increasing cure temperature. We examined the effect Na2SiO3/NaOH weight ratio on the properties of the geopolymers, too. It was seen that Na2SiO3/NaOH weight ratio was also important to prepare geopolymers that can be applied to construction industry.

Keywords: geopolymers, compressive strength, kaolinite, calcite

Procedia PDF Downloads 277
638 Feasibility of a Biopolymer as Lightweight Aggregate in Perlite Concrete

Authors: Ali A. Sayadi, Thomas R. Neitzert, G. Charles Clifton

Abstract:

Lightweight concrete is being used in the construction industry as a building material in its own right. Ultra-lightweight concrete can be applied as a filler and support material for the manufacturing of composite building materials. This paper is about the development of a stable and reproducible ultra-lightweight concrete with the inclusion of poly-lactic acid (PLA) beads and assessing the feasibility of PLA as a lightweight aggregate that will deliver advantages such as a more eco-friendly concrete and a non-petroleum polymer aggregate. In total, sixty-three samples were prepared and the effectiveness of mineral admixture, curing conditions, water-cement ratio, PLA ratio, EPS ratio and perlite ratio on compressive strength of perlite concrete are studied. The results show that PLA particles are sensitive to alkali environment of cement paste and considerably shrank and lost their strength. A higher compressive strength and a lower density was observed when expanded polystyrene (EPS) particles replaced PLA beads. In addition, a set of equations is proposed to estimate the water-cement ratio, cement content and compressive strength of perlite concrete.

Keywords: perlite concrete, poly-lactic acid (pla), expanded polystyrene (eps), concrete

Procedia PDF Downloads 283
637 A Road Map of Success for Differently Abled Adolescent Girls Residing in Pune, Maharashtra, India

Authors: Varsha Tol, Laila Garda, Neelam Bhardwaj, Malata Usar

Abstract:

In India, differently- abled girls suffer from a “dual stigma” of being female and physically challenged. The general consensus is that they are incapable of standing on their own two feet. It was observed that these girls do not have access to educational programs as most hostels do not keep them after the tenth grade. They are forced to return to a life of poverty and are often considered a liability by their families. Higher education is completely ignored. Parents focus on finding a husband and passing on their ‘burden’ to someone else. An innovative, intervention for differently-abled adolescent girls with the express purpose of mainstreaming them into society was started by Helplife. The objective was to enrich the lives of these differently abled adolescent girls through precise research, focused intervention and professionalism. This programme addresses physical, mental and social rehabilitation of the girls who come from impoverished backgrounds. These adolescents are reached by word of mouth, snowball technique and through the network of the NGO. Applications are invited from potential candidates which are scrutinized by a panel of experts. Selection criteria include her disability, socio-economic status, and desire and drive to make a difference in her own life. The six main areas of intervention are accommodation, education, health, professional courses, counseling and recreational activities. Each girl on an average resides in Helplife for a period of 2-3 years. Analysis of qualitative data collected at various time points indicates holistic development of character. A quality of life questionnaire showed a significant improvement in scores at three different time points in 75% of the current population under intervention i.e. 19 girls. Till date, 25 girls have successfully passed out from the intervention program completing their graduation/post-graduation. Currently, we have 19 differently abled girls housed in three flats in Pune district of Maharashtra. Out of which 14 girls are pursuing their graduation or post-graduation. Six of the girls are working in jobs in various sectors. In conclusion it may be noted with adequate support and guidance the sky is the limit. This journey of 12 years has been a learning for us with ups and downs modifying the intervention at every step. Helplife has a belief of impacting positively, individual lives of differently abled girls in order to empower them in a holistic manner. The intervention has a positive impact on differently abled girls. They serve as role models to other differently abled girls indicating that this is a road map to success by getting empowered to live with full potential and get integrated in the society in a dignified way.

Keywords: differently-abled, dual-stigma, empowerment, youth

Procedia PDF Downloads 132
636 Design of Photonic Crystal with Defect Layer to Eliminate Interface Corrugations for Obtaining Unidirectional and Bidirectional Beam Splitting under Normal Incidence

Authors: Evrim Colak, Andriy E. Serebryannikov, Pavel V. Usik, Ekmel Ozbay

Abstract:

Working with a dielectric photonic crystal (PC) structure which does not include surface corrugations, unidirectional transmission and dual-beam splitting are observed under normal incidence as a result of the strong diffractions caused by the embedded defect layer. The defect layer has twice the period of the regular PC segments which sandwich the defect layer. Although the PC has even number of rows, the structural symmetry is broken due to the asymmetric placement of the defect layer with respect to the symmetry axis of the regular PC. The simulations verify that efficient splitting and occurrence of strong diffractions are related to the dispersion properties of the Floquet-Bloch modes of the photonic crystal. Unidirectional and bi-directional splitting, which are associated with asymmetric transmission, arise due to the dominant contribution of the first positive and first negative diffraction orders. The effect of the depth of the defect layer is examined by placing single defect layer in varying rows, preserving the asymmetry of PC. Even for deeply buried defect layer, asymmetric transmission is still valid even if the zeroth order is not coupled. This transmission is due to evanescent waves which reach to the deeply embedded defect layer and couple to higher order modes. In an additional selected performance, whichever surface is illuminated, i.e., in both upper and lower surface illumination cases, incident beam is split into two beams of equal intensity at the output surface where the intensity of the out-going beams are equal for both illumination cases. That is, although the structure is asymmetric, symmetric bidirectional transmission with equal transmission values is demonstrated and the structure mimics the behavior of symmetric structures. Finally, simulation studies including the examination of a coupled-cavity defect for two different permittivity values (close to the permittivity values of GaAs or Si and alumina) reveal unidirectional splitting for a wider band of operation in comparison to the bandwidth obtained in the case of a single embedded defect layer. Since the dielectric materials that are utilized are low-loss and weakly dispersive in a wide frequency range including microwave and optical frequencies, the studied structures should be scalable to the mentioned ranges.

Keywords: asymmetric transmission, beam deflection, blazing, bi-directional splitting, defect layer, dual beam splitting, Floquet-Bloch modes, isofrequency contours, line defect, oblique incidence, photonic crystal, unidirectionality

Procedia PDF Downloads 162
635 Being a Doctor and Being Ethical: An Existentialist's Approach to a Meaningful Doctor-Patient Relationship

Authors: Gamith Mendis

Abstract:

Even though the doctors are knowledgeable, there's a gap between knowing and being ethical. This is a barrier to establish an ethical doctor-patient relationship. Current health system has oriented in a way that gives a meaning to both the doctor and the patient through intermediate entities. For the doctor, the meaning of the doctor-patient relationship is given through the financial benefits, promotions, and social status. For the patient, the meaning is given through curing of the disease. It is obvious that both are independent entities between the doctor and the patient. As the philosophers like Husserl and Heidegger have pointed out, our subjective world will give the immediate meaningfulness to us. We should seek this immediate meaningfulness of the doctor-patient relationship. The present research has used the existential methodology as guided self-reflections on the lived experiences of a doctor and his students. In this approach, two important aspects have been understood. The first is, establishing the fact that being ethical is itself giving meaningfulness to the doctor’s being without any mediate entities. Simply, it is enjoying being an honest being. The second is by being-with-the-patient while treating the disease; both the doctor and the patient can enjoy the meaningfulness of their human relationship. The medical students and the doctors should focus on this meaningfulness. For that, this discussion should be actively incorporated into the medical curriculum with programs of practical guidance to medical students and should be discussed in patient-care reviews in the health setting within a satisfactory framework.

Keywords: doctor-patient relationship, medical education, medical ethics, medical humanities, qualitative health research

Procedia PDF Downloads 129
634 Influence of Silica Fume on the Hydration of Cement Pastes Studied by Simultaneous TG-DSC Analysis

Authors: Anton Trník, Lenka Scheinherrová, Robert Černý

Abstract:

Silica fume is a by-product of the ferro-silicon and silicon metal industries. It is mainly in the form of amorphous silica. Silica fume belongs to pozzolanic active materials which can be used in concrete to improve its final properties. In this paper, the influence of silica fume on hydration of cement pastes is studied using differential scanning calorimetry (DSC) and thermogravimetry (TG) at various curing times (2, 7, 28, and 90 days) in the temperature range from 25 to 1000 °C in an argon atmosphere. Samples are prepared from Portland cement CEM I 42.5 R which is partially replaced with the silica fume of 4, 8, and 12 wt.%. The water/binder ratio is chosen as 0.5. It is identified and described the liberation of physically bound water, calcium–silicate–hydrates dehydration, portlandite and calcite decomposition in studied samples. Also, it is found out that an exothermic peak at 950 °C is observed without a significant mass change for samples with 12 wt.% of silica fume after two days of hydration. This peak is probably caused by the pozzolanic reaction between silica fume and Portland cement. Its size corresponds to the degree of crystallization between Ca and Si. The portlandite content is lower for the samples with a higher amount of silica fume.

Keywords: differential scanning calorimetry, hydration, silica fume, thermogravimetry

Procedia PDF Downloads 217
633 Understanding Farmers’ Perceptions Towards Agrivoltaics Using Decision Tree Algorithms

Authors: Mayuri Roy Choudhury

Abstract:

In recent times the concept of agrivoltaics has gained popularity due to the dual use of land and the added value provided by photovoltaics in terms of renewable energy and crop production on farms. However, the transition towards agrivoltaics has been slow, and our research tries to investigate the obstacles leading towards the slow progress of agrivoltaics. We applied data science decision tree algorithms to quantify qualitative perceptions of farmers in the United States for agrivoltaics. To date, there has not been much research that mentions farmers' perceptions, as most of the research focuses on the benefits of agrivoltaics. Our study adds value by putting forward the voices of farmers, which play a crucial towards the transition to agrivoltaics in the future. Our results show a mixture of responses in favor of agrivoltaics. Furthermore, it also portrays significant concerns of farmers, which is useful for decision-makers when it comes to formulating policies for agrivoltaics.

Keywords: agrivoltaics, decision-tree algorithms, farmers perception, transition

Procedia PDF Downloads 163
632 Influence of Bio-Based Admixture on Compressive Strength of Concrete for Columns

Authors: K. Raza, S. Gul, M. Ali

Abstract:

Concrete is a fundamental building material, extensively utilized by the construction industry. Problems related to the strength of concrete is an immense issue for the sustainability of concrete structures. Concrete mostly loses its strength due to the cracks produced in it by shrinkage or hydration process. This study aims to enhance the strength and service life of the concrete structures by incorporating bio-based admixture in the concrete. By the injection of bio-based admixture (BBA) in concrete, it will self-heal the cracks by producing calcium carbonate. Minimization of cracks will compact the microstructure of the concrete, due to which strength will increase. For this study, Bacillus subtilis will be used as a bio-based admixture (BBA) in concrete. Calcium lactate up to 1.5% will be used as the food source for the Bacillus subtilis in concrete. Two formulations containing 0 and 5% of Bacillus subtilis by weight of cement, will be used for the casting of concrete specimens. Direct mixing method will be adopted for the usage of bio-based admixture in concrete. Compressive strength test will be carried out after 28 days of curing. Scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) will be performed for the examination of micro-structure of concrete. Results will be drawn by comparing the test results of 0 and 5% the formulations. It will be recommended to use to bio-based admixture (BBA) in concrete for columns because of the satisfactory increase in the compressive strength of concrete.

Keywords: bio-based admixture, Bacillus subtilis, calcium lactate, compressive strength

Procedia PDF Downloads 192
631 On Copular Constructions in Yemeni Arabic and the Cartography of Subjects

Authors: Ameen Alahdal

Abstract:

This paper investigates copular constructions in Raimi Yemeni Arabic (RYA). The aim of the paper is actually twofold. First it explores the types of copular constructions in Raimi Yemeni Arabic, a variety of Arabic that has not attracted a lot of attention. In this connection, the paper shows that RYA manifests ‘bare’, verbal and pronominal/PRON copular constructions, just like other varieties of Arabic and indeed other Semitic languages like Hebrew. The sentences below from RYA represent the three constructions, respectively. (1) a. nada Hilwah Nada pretty.3sf ‘Nada is pretty’ b. kan al-banat hina was the-girls here ‘The girls were here c. ali hu-l mudiir Ali he-the manager ‘Ali is the manager’ Interestingly, in addition to these common types of copular constructions, RYA seems to exhibit dual copula sentences, a construction that features both a pronominal copula and a verbal copula. Such a construction is attested neither in Standard Arabic nor in other modern varieties of Arabic such as Lebanese, Moroccan, Egyptian, Jordanian. Remarkably, dual copular sentences do not appear even in other dialects of Yemeni Arabic such as Sanaani, Adeni and Tehami. (2) is an example. (2) maha kan-ih mudarrisah maha was-she teacher.3sf ‘Maha was a teacehr’ Second, the paper considers the cartography of subject positions in copular constructions proposed by Shlonsky and Rizzi (2018). Different copular constructions seem to involve different subject positions (which might eventually correlate with different interpretations – not our concern in this paper). Here, it is argued that in a bare copular sentence, as in (1a), RYA might exploit two criterial subject positions (in Rizzi’s sense), in addition to the canonical Spec,TP position. Under mainstream minimalist assumption, a copular sentence is analyzed as a PredP. Thus, in addition to the PredP-related thematic subject position, a criterial subject position is posited outside of PredP. (3) below represents the cartography of subject positions in a bare copular construction. (3) [……..DP subj PredP DP Pred DP/AP/PP ] In PRON sentences, as exemplified in (1c), another two subject positions are postulated high in the clause, particularly above PolP. (4) illustrates the hierarchy of the subject positions in a PRON copular construction. The subject resides in Spec,SUBJ2P. (4) …DP SUBJ2 …DP SUBJ1 … Pol … DP subj PredP Another related phenomenon in RYA which sets it apart from other languages like Hebrew is that of negative bare copular construction. This construction involves a PRON, which is not found in its affirmative counterpart. PRON, however, is hosted neither by SUBJ20 nor by SUBJ10. Rather, PRON occurs below Neg0 (Pol0 in the hierarchy). This situation raises interesting issues for the hierarchy of subjects in copular constructions as well as to the syntax of the left periphery in general. With regard to what causes the subject to move, there are different potential triggers. For instance, movement of the subject at the base, i.e., out of PredP is triggered by a labeling failure. Other movements of the subject can be driven by a formal feature like EPP, or a criterial feature like [subj].

Keywords: Yemeni Arabic, copular constructions, cartography of subjects, labeling, criterial positions

Procedia PDF Downloads 70
630 Influence of Modified and Unmodified Cow Bone on the Mechanical Properties of Reinforced Polyester Composites for Biomedical Applications

Authors: I. O. Oladele, J. A. Omotoyinbo, A. M. Okoro, A. G. Okikiola, J. L. Olajide

Abstract:

This work was carried out to investigate comparatively the effects of modified and unmodified cow bone particles on the mechanical properties of polyester matrix composites in order to investigate the suitability of the materials as biomaterial. Cow bones were procured from an abattoir, sun dried for 4 weeks and crushed. The crushed bones were divided into two, where one part was turned to ash while the other part was pulverized with laboratory ball mill before the two grades were sieved using 75 µm sieve size. Bone ash and bone particle reinforced tensile and flexural composite samples were developed from pre-determined proportions of 2, 4, 6, and 8 %. The samples after curing were stripped from the moulds and were allowed to further cure for 3 weeks before tensile and flexural tests were performed on them. The tensile test result showed that, 8 wt % bone particle reinforced polyester composites has higher tensile properties except for modulus of elasticity where 8 wt % bone ash particle reinforced composites has higher value while for flexural test, bone ash particle reinforced composites demonstrate the best flexural properties. The results show that these materials are structurally compatible.

Keywords: biomedical, composites, cow bone, mechanical properties, polyester, reinforcement

Procedia PDF Downloads 253
629 Effect of Rice Husk Ash on Strength and Durability of High Strength High Performance Concrete

Authors: H. B. Mahmud, Syamsul Bahri, Y. W. Yee, Y. T. Yeap

Abstract:

This paper reports the strength and durability properties of high strength high performance concrete incorporating rice husk ash (RHA) having high silica, low carbon content and appropriate fineness. In this study concrete containing 10%, 15% and 20% RHA as cement replacement and water to binder ratio of 0.25 were investigated. The results show that increasing amount of RHA increases the dosage of superplasticizer to maintain similar workability. Partial replacement of cement with RHA did not increase the early age compressive strength of concrete. However, concrete containing RHA showed higher compressive strength at later ages. The results showed that compressive strength of concrete in the 90-115 MPa range can be obtained at 28 curing days and the durability properties of RHA concrete performed better than that of control concrete. The water absorption of concrete incorporating 15% RHA exhibited the lowest value. The porosity of concrete is consistent with water absorption whereby higher replacement of RHA decreased the porosity of concrete. There is a positive correlation between reducing porosity and increasing compressive strength of high strength high performance concrete. The results also indicate that up to 20% of RHA incorporation could be advantageously blended with cement without adversely affecting the strength and durability properties of concrete.

Keywords: compressive strength, durability, high performance concrete, rice husk ash

Procedia PDF Downloads 308
628 Performance of Hybrid Image Fusion: Implementation of Dual-Tree Complex Wavelet Transform Technique

Authors: Manoj Gupta, Nirmendra Singh Bhadauria

Abstract:

Most of the applications in image processing require high spatial and high spectral resolution in a single image. For example satellite image system, the traffic monitoring system, and long range sensor fusion system all use image processing. However, most of the available equipment is not capable of providing this type of data. The sensor in the surveillance system can only cover the view of a small area for a particular focus, yet the demanding application of this system requires a view with a high coverage of the field. Image fusion provides the possibility of combining different sources of information. In this paper, we have decomposed the image using DTCWT and then fused using average and hybrid of (maxima and average) pixel level techniques and then compared quality of both the images using PSNR.

Keywords: image fusion, DWT, DT-CWT, PSNR, average image fusion, hybrid image fusion

Procedia PDF Downloads 575
627 Genetic Variations of Two Casein Genes among Maghrabi Camels Reared in Egypt

Authors: Othman E. Othman, Amira M. Nowier, Medhat El-Denary

Abstract:

Camels play an important socio-economic role within the pastoral and agricultural system in the dry and semidry zones of Asia and Africa. Camels are economically important animals in Egypt where they are dual purpose animals (meat and milk). The analysis of chemical composition of camel milk showed that the total protein contents ranged from 2.4% to 5.3% and it is divided into casein and whey proteins. The casein fraction constitutes 52% to 89% of total camel milk protein and it divided into 4 fractions namely αs1, αs2, β and κ-caseins which are encoded by four tightly genes. In spite of the important role of casein genes and the effects of their genetic polymorphisms on quantitative traits and technological properties of milk, the studies for the detection of genetic polymorphism of camel milk genes are still limited. Due to this fact, this work focused - using PCR-RFP and sequencing analysis - on the identification of genetic polymorphisms and SNPs of two casein genes in Maghrabi camel breed which is a dual purpose camel breed in Egypt. The amplified fragments at 488-bp of the camel κ-CN gene were digested with AluI endonuclease. The results showed the appearance of three different genotypes in the tested animals; CC with three digested fragments at 203-, 127- and 120-bp, TT with three digested fragments at 203-, 158- and 127-bp and CT with four digested fragments at 203-, 158-, 127- and 120-bp. The frequencies of three detected genotypes were 11.0% for CC, 48.0% for TT and 41.0% for CT genotypes. The sequencing analysis of the two different alleles declared the presence of a single nucleotide polymorphism (C→T) at position 121 in the amplified fragments which is responsible for the destruction of a restriction site (AG/CT) in allele T and resulted in the presence of two different alleles C and T in tested animals. The nucleotide sequences of κ-CN alleles C and T were submitted to GenBank with the accession numbers; KU055605 and KU055606, respectively. The primers used in this study amplified 942-bp fragments spanning from exon 4 to exon 6 of camel αS1-Casein gene. The amplified fragments were digested with two different restriction enzymes; SmlI and AluI. The results of SmlI digestion did not show any restriction site whereas the digestion with AluI endonuclease revealed the presence of two restriction sites AG^CT at positions 68^69 and 631^632 yielding the presence of three digested fragments with sizes 68-, 563- and 293-bp.The nucleotide sequences of this fragment from camel αS1-Casein gene were submitted to GenBank with the accession number KU145820. In conclusion, the genetic characterization of quantitative traits genes which are associated with the production traits like milk yield and composition is considered an important step towards the genetic improvement of livestock species through the selection of superior animals depending on the favorable alleles and genotypes; marker assisted selection (MAS).

Keywords: genetic polymorphism, SNP polymorphism, Maghrabi camels, κ-Casein gene, αS1-Casein gene

Procedia PDF Downloads 586
626 Impact of Glaucoma Surgery on Corneal Endothelium

Authors: Majid Moshirfar, Kyle Margulies, Yasmyne C. Ronquillo, Phillip Hoopes

Abstract:

A total of 66 articles were reviewed to compare glaucoma and its associated surgeries' effect on central corneal endothelium cell density (CECD). The paper reports the average reported central CECD loss at 3-, 6-, 12-, 24-, 36-, 48-, and 60-month post-operation for each glaucoma surgery. ALT, MLT, SLT, CS AGV, VC BGI, Hydrus + phaco, XEN gel + phaco, PRESERFLO, Dual iStent, or Trabectome had no significant impact on postoperative CECD compared to either preoperative CECD or control group CECD. The highest CECD loss was found to be EXPRESS-phaco, AC AGV, CS BGI, CS BGI, AC BGI, and AC BGI at the 3-, 6-, 12-, 24-, 36-, 48-, and 60-month follow-ups, respectively. AC AGV, Trab + MMC, Trab, AC BGI, Trab + MMC, Cypass, and Cypass showed the smallest reduction of CECD at the 3-, 6-, 12-, 24-, 36-, 48-, and 60-month follow-ups.

Keywords: glaucoma, corneal endothelium, cell density, surgery outcome

Procedia PDF Downloads 72
625 Time Delay Estimation Using Signal Envelopes for Synchronisation of Recordings

Authors: Sergei Aleinik, Mikhail Stolbov

Abstract:

In this work, a method of time delay estimation for dual-channel acoustic signals (speech, music, etc.) recorded under reverberant conditions is investigated. Standard methods based on cross-correlation of the signals show poor results in cases involving strong reverberation, large distances between microphones and asynchronous recordings. Under similar conditions, a method based on cross-correlation of temporal envelopes of the signals delivers a delay estimation of acceptable quality. This method and its properties are described and investigated in detail, including its limits of applicability. The method’s optimal parameter estimation and a comparison with other known methods of time delay estimation are also provided.

Keywords: cross-correlation, delay estimation, signal envelope, signal processing

Procedia PDF Downloads 459
624 Valorization of Clay Material in the Road Sector By Adding Granulated Recycled Plastic

Authors: Ouaaz Oum Essaad, Melbouci Bachir

Abstract:

The experimental study conducted has a dual purpose: to valorize the clay material in the road domain and improve the lift of the shape layers by strengthening with plastic waste (in the form of aggregates). To do this, six mixtures of Clay and sand of different percentages were studied: 100% Clay, 95% Clay + 05% Sand, 90% Clay + 10% Sand, 85% Clay + 15% Sand, 80% Clay + 20% Sand, 75% Clay + 25% Sand. Proctor compaction and simple compression tests have been carried out on mixtures (sand + clay + plastic waste). The results obtained show a clear evolution of the characteristics of the Proctor test and the compressive strength of the mixtures according to the different types and percentages of the recycled plastic Plasticity and consistency index are important parameters that play a role in the toughness of plastic soil.

Keywords: valorization, recycling, soil mixture, mechanical tests

Procedia PDF Downloads 71
623 Supplier Selection by Bi-Objectives Mixed Integer Program Approach

Authors: K.-H. Yang

Abstract:

In the past, there was a lot of excellent research studies conducted on topics related to supplier selection. Because the considered factors of supplier selection are complicated and difficult to be quantified, most researchers deal supplier selection issues by qualitative approaches. Compared to qualitative approaches, quantitative approaches are less applicable in the real world. This study tried to apply the quantitative approach to study a supplier selection problem with considering operation cost and delivery reliability. By those factors, this study applies Normalized Normal Constraint Method to solve the dual objectives mixed integer program of the supplier selection problem.

Keywords: bi-objectives MIP, normalized normal constraint method, supplier selection, quantitative approach

Procedia PDF Downloads 386
622 Air Access Liberalisation and Tourism Trade Evidence from a Sids

Authors: Seetanah Boopen, R. V. Sannassee

Abstract:

The objective of the present study is two-fold. Firstly, to assess the impact of air access liberalization on tourism demand for Mauritius and secondly to analyses the dual impact of the interplay between air access liberalization and marketing promotion efforts on tourism demand. Using an Autoregressive Distributed Lag model, the results suggest that air access liberalization is an important ingredient, albeit to a lesser extent as compared to other classical explanatory variables, of tourism demand. The results also highlight the fact that Mauritius is perceived as a luxurious destination and tourists are deemed price sensitive. Moreover, our dynamic approach interestingly confirms the presence of repeat tourism in the island. Finally, the findings also uncover the positive impact of the interplay between air access liberalization and marketing promotion efforts on fostering tourism demand.

Keywords: air access liberalization, ARDL, SIDS, time series

Procedia PDF Downloads 284
621 Quantization of Damped Systems Based on the Doubling of Degrees of Freedom

Authors: Khaled I. Nawafleh

Abstract:

In this paper, it provide the canonical approach for studying dissipated oscillators based on the doubling of degrees of freedom. Clearly, expressions for Lagrangians of the elementary modes of the system are given, which ends with the familiar classical equations of motion for the dissipative oscillator. The equation for one variable is the time reversed of the motion of the second variable. it discuss in detail the extended Bateman Lagrangian specifically for a dual extended damped oscillator time-dependent. A Hamilton-Jacobi analysis showing the equivalence with the Lagrangian approach is also obtained. For that purpose, the techniques of separation of variables were applied, and the quantization process was achieved.

Keywords: doubling of degrees of freedom, dissipated harmonic oscillator, Hamilton-Jacobi, time-dependent lagrangians, quantization

Procedia PDF Downloads 45
620 Investigating the Fiber Content, Fiber Length, and Curing Characteristics of 3D Printed Recycled Carbon Fiber

Authors: Peng Hao Wang, Ronald Sterkenburg, Garam Kim, Yuwei He

Abstract:

As composite materials continue to gain popularity in the aerospace industry; large airframe sections made out of composite materials are becoming the standard for aerospace manufacturers. However, the heavy utilization of these composite materials also increases the importance of the recycling of these composite materials. A team of Purdue University School of Aviation and Transportation Technology (SATT) faculty and students have partnered to investigate the characteristics of 3D printed recycled carbon fiber. A prototype of a 3D printed recycled carbon fiber part was provided by an industry partner and different sections of the prototype were used to create specimens. A furnace was utilized in order to remove the polymer from the specimens and the specimen’s fiber content and fiber length was calculated from the remaining fibers. A differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) test was also conducted on the 3D printed recycled carbon fiber prototype in order to determine the prototype’s degree of cure at different locations. The data collected from this study provided valuable information in the process improvement and understanding of 3D printed recycled carbon fiber.

Keywords: 3D printed, carbon fiber, fiber content, recycling

Procedia PDF Downloads 157
619 Cholinesterase Inhibitory Indole Alkaloids from the Bark of Rauvolfia reflexa

Authors: Mehran Fadaeinasab, Alireza Basiri, Yalda Kia, Hamed Karimian, Hapipah Mohd Ali, Vikneswaran Murugaiyah

Abstract:

Two new, rauvolfine C and 3- methyl-10,11-dimethoxyl-6- methoxycarbonyl- β- carboline, along with five known indole alkaloids, macusine B, vinorine, undulifoline, isoresrpiline and rescinnamine were isolated from the bark of Rauvolfia reflexa. All the compounds showed good to moderate cholinesterase inhibitory activity with IC50 values in the range of 8.06 to 73.23 πM, except rauvolfine C that was inactive against acetylcholinesterase (AChE). Rescinnamine, a dual inhibitor was found to be the most potent inhibitor among the isolated alkaloids against both AChE and butyrylcholinesterase (BChE). Molecular docking revealed that rescinnamine interacted differently on AChE and BChE, by means of hydrophobic interactions and hydrogen bonding.

Keywords: Rauvolfia reflexa, indole alkaloids, acetylcholinesterase, butyrylcholinesterase, molecular docking

Procedia PDF Downloads 560
618 Association between Occupational Characteristics and Well-Being: An Exploratory Study of Married Working Women in New Delhi, India

Authors: Kanchan Negi

Abstract:

Background: Modern and urban occupational culture have driven demands for people to work long hours and weekends and take work to home at times. Research on the health effects of these exhaustive temporal work patterns is scant or contradictory. This study examines the relationship between work patterns and wellbeing in a sample of women living in the metropolitan hub of Delhi. Method: This study is based on the data collected from 360 currently married women between age 29 and 49 years, working in the urban capital hub of India, i.e., Delhi. The women interviewed were professionals from the education, health, banking and information and technology (IT) sector. Bivariate analysis was done to study the characteristics of the sample. Logistic regression analysis was used to estimate the physical and psychological wellbeing across occupational characteristics. Results: Most of the working women were below age 35 years; around 30% of women worked in the education sector, 23% in health, 21% in banking and 26% in the IT sector. Over 55% of women were employed in the private sector and only 36% were permanent employees. Nearly 30% of women worked for more than the standard 8 hours a day. The findings from logistic regression showed that compared to women working in the education sector, those who worked in the banking and IT sector more likely to have physical and psychological health issues (OR 2.07-4.37, CI 1.17-4.37); women who bear dual burden of responsibilities had higher odds of physical and psychological health issues than women who did not (OR 1.19-1.85 CI 0.96-2.92). Women who worked for more than 8 hours a day (OR 1.15, CI 1.01-1.30) and those who worked for more than five days a week (OR 1.25, CI 1.05-1.35) were more likely to have physical health issues than women who worked for 6-8 hours a day and five days e week, respectively. Also, not having flexible work timings and compensatory holidays increased the odds of having physical and psychological health issues among working women (OR 1.17-1.29, CI 1.01-1.47). Women who worked in the private sector, those employed temporarily and who worked in the non-conducive environments were more likely to have psychological health issues as compared to women in the public sector, permanent employees and those who worked in a conducive environment, respectively (OR 1.33-1.67, CI 1.09-2.91). Women who did not have poor work-life balance had reduced the odds of psychological health issues than women with poor work-life balance (OR 0.46, CI 0.25-0.84). Conclusion: Poor wellbeing significantly linked to strenuous and rigid work patterns, suggesting that modern and urban work culture may contribute to the poor wellbeing of working women. Noticing the recent decline in female workforce participation in Delhi, schemes like Flexi-timings, compensatory holidays, work-from-home and daycare facilities for young ones must be welcomed; these policies already exist in some private sector firms, and the public sectors companies should also adopt such changes to ease the dual burden as homemaker and career maker. This could encourage women in the urban areas to readily take up the jobs with less juggle to manage home and work.

Keywords: occupational characteristics, urban India, well-being, working women

Procedia PDF Downloads 180
617 Role of Bariatric Surgery in Polycystic Ovarian Syndrome &Infertility

Authors: Ahuja Ashish, Nain Prabhdeep Singh

Abstract:

Introduction: Polycystic ovarian syndrome(PCOS) is the most common endocrine disorder among women of reproductive age.Pcos encompasses a broad spectrum of signs&symptoms of ovary dysfunction,obesity,blood pressure,insulin resistance & infertility. Bariatric Surgery can be an effective means of weight loss in Pcos & curing infertility. Materials and Methods: 15 female patients were enrolled in the study from 2012-2014.66%(n=10) were in age group of 20-25 years,33%(n=5) were in age group of 25-33 years who underwent. Bariatric surgery in form of Laproscopic sleeve Gastrectomy(LSG)& Roux-en-Y gastric bypass. LSG 73%(n=11), RYGB26% (n=4). Results: There was a significant improvement in obesity (60% excess weight loss)over 1 year after bariatric surgery, in 12 patients there was gross improvement in restoration of menstrual cycle who had irregular menstrual cycle. In 80% patients the serum insulin level showed normal value. Over two years 8 patients become pregnant. Conclusions: 1)Obese women with Pcos maybe able to conceive after Bariatric Surgery. 2) Women with Pcos should only consider bariatric surgery if they were already considering it for other reasons to treat obesity, blood pressure & other co-morbid conditions.

Keywords: obesity, bariatric surgery, polycystic ovarian syndrome, infertility

Procedia PDF Downloads 273
616 Effect of Nanobentonite Particles on Geotechnical Properties of Kerman Clay

Authors: A. Ghasemipanah, R. Ziaie Moayed, H. Niroumand

Abstract:

Improving the geotechnical properties of soil has always been one of the issues in geotechnical engineering. Traditional materials have been used to improve and stabilize soils to date, each with its own advantages and disadvantages. Although the soil stabilization by adding materials such as cement, lime, bitumen, etc. is one of the effective methods to improve the geotechnical properties of soil, but nanoparticles are one of the newest additives which can improve the loose soils. This research is intended to study the effect of adding nanobentonite on soil engineering properties, especially the unconfined compression strength and maximum dry unit weight, using clayey soil with low liquid limit (CL) from Kerman (Iran). Nanobentonite was mixed with soil in three different percentages (i.e. 3, 5, 7% by weight of the parent soil) with different curing time (1, 7 and 28 days). The unconfined compression strength, liquid and plastic limits and plasticity index of treated specimens were measured by unconfined compression and Atterberg limits test. It was found that increase in nanobentonite content resulted in increase in the unconfined compression strength, liquid and plastic limits of the clayey soil and reduce in plasticity index.

Keywords: nanobentonite particles, clayey soil, unconfined compression stress, soil improvement.

Procedia PDF Downloads 100
615 Study of the Efficacy of Cysteine Protease Inhibitors Alone or Combined with Praziquantel as Chemotherapy for Mice Schistosomiasis mansoni

Authors: Alyaa Ahmed Farid, Aida Ismail, Ibrahim Rabia, Azza Fahmy, Azza El Amir

Abstract:

This study was designed for assessment of 3 types of Cysteine protease inhibitors (CPIs) fluromethylketone (FMK), vinyl sulfone (VS) and sodium nitro prussid (SNP), to define which of them is the best? The experiments aimed to define the protective power of each inhibitor alone or combined with PZQ for curing S. mansoni infection in mice. In vitro, treated S. mansoni adult worms recorded a mortality rate after 1 hr of exposure to 500 ppm of FMK, VS and SNP as 75, 70 and 60%, while, treated cercaria recorded 75, 60 and 50%, respectively. FMK+PZQ treatment recorded the maximum reduction in worm burden (97.2% at 5 wk PI). VS treatment alone or combined with PZQ increases IgM, total IgG, IgG2 and IgG4 levels. In EM study of worm tegument, while only detachment of spines was observed in PZQ treated group, the completely implanted spines were reported in the degenerated tegument of adult worms in all groups treated with CPIs. Treatment with VS+PZQ increased Igs levels but, its effect was different on worm reduction. So, it is not enough to eliminate the infection and FMK+PZQ considered the antischistosomicidal drug of choice.

Keywords: praziquantel, fluromethylketone, vinyl sulfone, worm burden, immunoglobulin pattern

Procedia PDF Downloads 343
614 Strongly Disordered Conductors and Insulators in Holography

Authors: Matthew Stephenson

Abstract:

We study the electrical conductivity of strongly disordered, strongly coupled quantum field theories, holographically dual to non-perturbatively disordered uncharged black holes. The computation reduces to solving a diffusive hydrostatic equation for an emergent horizon fluid. We demonstrate that a large class of theories in two spatial dimensions have a universal conductivity independent of disorder strength, and rigorously rule out disorder-driven conductor-insulator transitions in many theories. We present a (fine-tuned) axion-dilaton bulk theory which realizes the conductor-insulator transition, interpreted as a classical percolation transition in the horizon fluid. We address aspects of strongly disordered holography that can and cannot be addressed via mean-field modeling, such as massive gravity.

Keywords: theoretical physics, black holes, holography, high energy

Procedia PDF Downloads 152
613 Effect of Rice Husk Ash on Properties of Cold Bituminous Emulsion Mix

Authors: Sampada Katekar, Namdeo Hedaoo

Abstract:

Cold Bituminous Emulsion Mixtures (CBEMs) are generally produced by mixing unheated aggregate, binder and filler at ambient temperature. Cold bituminous emulsion mixtures have several environmental and cost-effective benefits. But CBEMs offer poor early life properties too and they require long curing time to achieve maximum strength. The main focus of this study is to overcome inferiority of CBEMs by incorporating Rice Husk Ash (RHA) and Ordinary Portland Cement (OPC). In this study, RHA and OPC are substituted for conventional mineral filler in an increased percentage from 0 to 3% with an increment of 1%. Marshall stability, retained stability and tensile strength tests were conducted to evaluate the enhancement in performance of CBEMs. The experimental results have shown that Marshall stability and tensile strength of CBEMs increased significantly by replacing the conventional mineral filler with RHA and OPC. The addition of RHA and OPC in CBEMs result in a reduction in moisture induced damages. However, stability and tensile strength values of RHA modified CBEMs are higher than that of OPC modified CBEMs.

Keywords: cold bituminous emulsion mixtures, Marshall stability test, ordinary Portland cement, rice husk ash

Procedia PDF Downloads 145
612 BOX Effect Sensitivity to Fin Width in SOI-Multi-FinFETs

Authors: A. N. Moulai Khatir

Abstract:

SOI-Multifin-FETs are placed to be the workhorse of the industry for the coming few generations, and thus, in a few years because their excellent transistor characteristics, ideal sub-threshold swing, low drain induced barrier lowering (DIBL) without pocket implantation, and negligible body bias dependency. The corner effect may also exist in the two lower corners; this effect is called the BOX effect, which can also occur in the direction X-Z. The electric field lines from the source and drain cross the bottom oxide and arrive in the silicon. This effect is also called DIVSB (Drain Induced Virtual Substrate Basing). The potential in the silicon film in particular near the drain is increased by the drain bias. It is similar to DIBL and result in a decrease of the threshold voltage. This work provides an understanding of the limitation of this effect by reducing the fin width for components with increased fin number.

Keywords: SOI, finFET, corner effect, dual-gate, tri-gate, BOX, multi-finFET

Procedia PDF Downloads 469
611 Determination of Resistance to Freezing of Bonded Façade Joint

Authors: B. Nečasová, P. Liška, J. Šlanhof

Abstract:

Verification of vented wooden façade system with bonded joints is presented in this paper. The potential of bonded joints is studied and described in more detail. The paper presents the results of an experimental and theoretical research about the effects of freeze cycling on the bonded joint. For the purpose of tests spruce timber profiles were chosen for the load bearing substructure. Planks from wooden plastic composite and Siberian larch are representing facade cladding. Two types of industrial polyurethane adhesives intended for structural bonding were selected. The article is focused on the preparation as well as on the subsequent curing and conditioning of test samples. All test samples were subjected to 15 cycles that represents sudden temperature changes, i.e. immersion in a water bath at (293.15 ± 3) K for 6 hours and subsequent freezing to (253.15 ± 2) K for 18 hours. Furthermore, the retention of bond strength between substructure and cladding was tested and strength in shear was determined under tensile stress. Research data indicate that little, if any, damage to the bond results from freezing cycles. Additionally, the suitability of selected group of adhesives in combination with timber substructure was confirmed.

Keywords: adhesive system, bonded joints, wooden lightweight façade, timber substructure

Procedia PDF Downloads 371
610 Therapeutic Challenges in Treatment of Adults Bacterial Meningitis Cases

Authors: Sadie Namani, Lindita Ajazaj, Arjeta Zogaj, Vera Berisha, Bahrije Halili, Luljeta Hasani, Ajete Aliu

Abstract:

Background: The outcome of bacterial meningitis is strongly related to the resistance of bacterial pathogens to the initial antimicrobial therapy. The objective of the study was to analyze the initial antimicrobial therapy, the resistance of meningeal pathogens and the outcome of adults bacterial meningitis cases. Materials/methods: This prospective study enrolled 46 adults older than 16 years of age, treated for bacterial meningitis during the years 2009 and 2010 at the infectious diseases clinic in Prishtinë. Patients are categorized into specific age groups: > 16-26 years of age (10 patients), > 26-60 years of age (25 patients) and > 60 years of age (11 patients). All p-values < 0.05 were considered statistically significant. Data were analyzed using Stata 7.1 and SPSS 13. Results: During the two year study period 46 patients (28 males) were treated for bacterial meningitis. 33 patients (72%) had a confirmed bacterial etiology; 13 meningococci, 11 pneumococci, 7 gram-negative bacilli (Ps. aeruginosa 2, Proteus sp. 2, Acinetobacter sp. 2 and Klebsiella sp. 1 case) and 2 staphylococci isolates were found. Neurological complications developed in 17 patients (37%) and the overall mortality rate was 13% (6 deaths). Neurological complications observed were: cerebral abscess (7/46; 15.2%), cerebral edema (4/46; 8.7%); haemiparesis (3/46; 6.5%); recurrent seizures (2/46; 4.3%), and single cases of thrombosis sinus cavernosus, facial nerve palsy and decerebration (1/46; 2.1%). The most common meningeal pathogens were meningococcus in the youngest age group, gram negative-bacilli in second age group and pneumococcus in eldery age group. Initial single-agent antibiotic therapy (ceftriaxone) was used in 17 patients (37%): in 60% of patients in the youngest age group and in 44% of cases in the second age group. 29 patients (63%) were treated with initial dual-agent antibiotic therapy; ceftriaxone in combination with vancomycin or ampicillin. Ceftriaxone and ampicillin were the most commonly used antibiotics for the initial empirical therapy in adults > 50 years of age. All adults > 60 years of age were treated with the initial dual-agent antibiotic therapy as in this age group was recorded the highest mortality rate (M=27%) and adverse outcome (64%). Resistance of pathogens to antimicrobics was recorded in cases caused by gram-negative bacilli and was associated with greater risk for developing neurological complications (p=0.09). None of the gram-negative bacilli were resistant to carbapenems; all were resistant to ampicillin while 5/7 isolates were resistant to cefalosporins. Resistance of meningococci and pneumococci to beta-lactams was not recorded. There were no statistical differences in the occurrence of neurological complications (p > 0.05), resistance of meningeal pathogens to antimicrobics (p > 0.05) and the inital antimicrobial therapy (one vs. two antibiotics) concerning group-ages in adults. Conclusions: The initial antibiotic therapy with ceftriaxone alone or in combination with vancomycin or ampicillin did not cover cases caused by gram-negative bacilli.

Keywords: adults, bacterial meningitis, outcomes, therapy

Procedia PDF Downloads 151