Search results for: degree of bending (DoB)

Authors: Adu-Ampomah Yaw Junior

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Local procurement has become one of the latest trends in the discourse of sustainable tourism due to the economic benefits it generates for tourist destinations in developing countries. Local procurement helps in creating jobs which consequently helps in alleviating poverty. However, there have been limited studies on local procurement patterns in developing countries. Research on hotel procurement practices has mainly emphasized the challenges that hoteliers face when procuring locally, leaving questions regarding their motivations to engage in local procurement unanswered. The institutional theory provides a suitable framework to better understand these motivations as it underlines the importance of individual cognitive perceptions on issues in shaping organizational response strategies. More specifically, the extent to which an issue is perceived to belong to the organization’s responsibility. Also the organizational actors’ belief of losses or gains resultant from acting or not acting on an issue (degree of importance). Furthermore the organizational actors’ belief of the probability of resolving an issue (degree of feasibility). These factors influence how an organization will act on this issue. Hence, this paper adopts an institutional perspective to examine local procurement patterns of food by hoteliers in Ghana. Qualitative interviews with 20 procurement managers about their procurement practices and motivations, as well as interviews with different stakeholders for data triangulation purposes, indicated that most hotels sourced their food from middlemen who imported most of their products. However, direct importation was more prevalent foreign owned hotels as opposed to locally owned ones. Notwithstanding, the importation and the usage of foreign foods as opposed to local ones can be explained by the lack of pressure from NGOs and trade associations on hotels to act responsibly. Though guests’ menu preferences were perceived as important to hoteliers business operations, western tourists demand foreign food primarily with the foreign owned hotels make it less important to procure local produce. Lastly hoteliers, particularly those in foreign owned ones, perceive local procurement to be less feasible, raising concerns about quality and variety of local produce. The paper outlines strategies to improve the perception and degree of local Firstly, there is the need for stakeholder engagement in order to make hoteliers feel responsible for acting on the issue.Again it is crucial for Ghana government to promote and encourage hotels to buy local produce. Also, the government has to also make funds and storage facilities available for farmers to impact on the quality and quantity of local produce. Moreover, Sites need to be secured for farmers to engage in sustained farming.Furthermore, there is the need for collaborations between various stakeholders to organize training programs for farmers. Notwithstanding hotels need to market local produce to their guests. Finally, the Ghana hotels association has to encourage hotels to indulge in local procurement.

Keywords: sustainable tourism, feasible, important, local procurement

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Authors: Shantanu Arya, Sachin Sakhuja, Gunjan Mehta, Sanjay Munjal

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Stuttering may be defined as a speech disorder affecting the fluency domain of speech and characterized by covert features like word substitution, omittance and circumlocution and overt features like prolongation of sound, syllables and blocks etc. Many etiologies have been postulated to explain stuttering based on various experiments and research. Moreover, Breathlessness has also been reported by many individuals with stuttering for which breathing exercises are generally advised. However, no studies reporting objective evaluation of the pulmonary capacity and further objective assessment of the efficacy of breathing exercises have been conducted. Pulmonary Function Test which evaluates parameters like Forced Vital Capacity, Peak Expiratory Flow Rate, Forced expiratory flow Rate can be used to study the pulmonary behavior of individuals with stuttering. The study aimed: a) To identify speech motor & physiologic behaviours associated with stuttering by administering PFT. b) To recognize possible reasons for an association between speech motor behaviour & stuttering severity. In this regard, PFT tests were administered on individuals who reported signs and symptoms of stuttering and showed abnormal scores on Stuttering Severity Index. Parameters like Forced Vital Capacity, Forced Expiratory Volume, Peak Expiratory Flow Rate (L/min), Forced Expiratory Flow Rate (L/min) were evaluated and correlated with scores of Stuttering Severity Index. Results showed significant decrease in the parameters (lower than normal scores) in individuals with established stuttering. Strong correlation was also found between degree of stuttering and the degree of decrease in the pulmonary volumes. Thus, it is evident that fluent speech requires strong support of lung pressure and requisite volumes. Further research in demonstrating the efficacy of abdominal breathing exercises in this regard is needed.

Keywords: forced expiratory flow rate, forced expiratory volume, forced vital capacity, peak expiratory flow rate, stuttering

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Authors: Taehoon Kwon, Hyeongrae Cho, Dirk Henkensmeier, Youngjong Kang, Chong Min Koo

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Ionic polymer actuators have been of interest in the bio-inspired artificial muscle devices. However, the relatively slow response and low power density were the obstacles for practical applications. In this study, ionic polymer actuators are fabricated with ionic polymer composite membranes based on sulfonated poly(arylene ether sulfone) (SPAES) and copper(II) phthalocyanine tetrasulfonic acid (CuPCSA). CuPCSA is an organic filler with very high ion exchange capacity (IEC, 4.5 mmol H+/g) that can be homogeneously dispersed on the molecular scale into the SPAES membrane. SPAES/CuPCSA actuators show larger ionic conductivity, mechanical properties, bending deformation, exceptional faster response to electrical stimuli, and larger mechanical power density (3028 W m–3) than Nafion actuators. This outstanding actuation performance of SPAES/CuPCSA composite membrane actuators makes them attractive for next generation transducers with high power density, which are currently developed biomimetic devices such as endoscopic surgery.

Keywords: actuation performance, composite membranes, ionic polymer actuators, organic filler

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Authors: A. A. Adebayo, O. Osibanjo

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Informal electronic waste (e-waste) processing is a crude method of recycling, which is on the increase in Nigeria. The release of hazardous substances such as heavy metals (HMs) into the environment during informal e-waste processing has been a major concern. However, there is insufficient information on environmental contamination from e-waste recycling, associated ecological risk in Alaba International Market, a major electronic market in Lagos, Nigeria. The aims of this study were to determine the levels of HMs in soil, resulting from the e-waste recycling; and also assess associated ecological risks in Alaba international market. Samples of soils (334) were randomly collected seasonally for three years from fourteen selected e-waste activity points and two control sites. The samples were digested using standard methods and HMs analysed by inductive coupled plasma optical emission. Ecological risk was estimated using Ecological Risk index (ER), Potential Ecological Risk index (RI), Index of geoaccumulation (Igeo), Contamination factor (Cf) and degree of contamination factor (Cdeg). The concentrations range of HMs (mg/kg) in soil were: 16.7-11200.0 (Pb); 14.3-22600.0 (Cu); 1.90-6280.0 (Ni), 39.5-4570.0 (Zn); 0.79-12300.0 (Sn); 0.02-138.0 (Cd); 12.7-1710.0 (Ba); 0.18-131.0 (Cr); 0.07-28.0 (V), while As was below detection limit. Concentrations range in control soils were 1.36-9.70 (Pb), 2.06-7.60 (Cu), 1.25-5.11 (Ni), 3.62-15.9 (Zn), BDL-0.56 (Sn), BDL-0.01 (Cd), 14.6-47.6 (Ba), 0.21–12.2 (Cr) and 0.22-22.2 (V). The trend in ecological risk index was in the order Cu > Pb > Ni > Zn > Cr > Cd > Ba > V. The potential ecological risk index with respect to informal e-waste activities were: burning > dismantling > disposal > stockpiling. The index of geo accumulation indices revealed that soils were extremely polluted with Cd, Cu, Pb, Zn and Ni. The contamination factor indicated that 93% of the studied areas have very high contamination status for Pb, Cu, Ba, Sn and Co while Cr and Cd were in the moderately contaminated status. The degree of contamination decreased in the order of Sn > Cu > Pb >> Zn > Ba > Co > Ni > V > Cr > Cd. Heavy metal contamination of Alaba international market environment resulting from informal e-waste processing was established. Proper management of e-waste and remediation of the market environment are recommended to minimize the ecological risks.

Keywords: Alaba international market, ecological risk, electronic waste, heavy metal contamination

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Authors: Ayşe Dilek Maden

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For a given a simple connected graph, we present some new bounds via a new approach for a special topological index given by the sum of the real number power of the non-zero normalized Laplacian eigenvalues. To use this approach presents an advantage not only to derive old and new bounds on this topic but also gives an idea how some previous results in similar area can be developed.

Keywords: degree Kirchhoff index, normalized Laplacian eigenvalue, spanning tree, simple connected graph

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Authors: S. Larbi, R. Bensaada, S. Djebali, A. Bilek

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The manufacture of composite parts is a major issue in many industrial domains. Polymer composite materials are ideal for structural applications where high strength-to-weight and stiffness-to-weight ratios are required. However, exposition to extreme environment conditions (temperature, humidity) affects mechanical properties of organic composite materials and lead to an undesirable degradation. Aging mechanisms in organic matrix are very diverse and vary according to the polymer and the aging conditions such as temperature, humidity etc. This paper studies the hygrothermal aging effect on the mechanical properties of fiber reinforced plastics laminates at 40 °C in different environment exposure. Two composite materials are used to conduct the study (carbon fiber/epoxy and glass fiber/vinyl ester with two stratifications for both the materials [904/04] and [454/04]). The experimental procedure includes a mechanical characterization of the materials in a virgin state and exposition of specimens to two environments (seawater and demineralized water). Absorption kinetics for the two materials and both the stratifications are determined. Three-point bending test is performed on the aged materials in order to determine the hygrothermal effect on the mechanical properties of the materials.

Keywords: FRP laminates, hygrothermal aging, mechanical properties, theory of laminates

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Authors: Ali M. Babalghaith, Hamad A. Alsoliman, Abdulrahman S. Al-Suhaibani

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Flexible pavement made with neat asphalt binder is not enough to resist heavy traffic loads as well as harsh environmental condition found in Riyadh region. Therefore, there is a need to modify asphalt binder with polymers to satisfy such conditions. There are several types of polymers that are used to modify asphalt binder. The objective of this paper is to compare the rheological properties of six polymer modified asphalt binders (Lucolast7010, Anglomak2144, Paveflex140, SBS KTR401, EE-2 and Crumb rubber) obtained from asphalt manufacturer plants. The rheological properties of polymer modified asphalt binders were tested using conventional tests such as penetration, softening point and viscosity; and SHRP tests such as dynamic shear rheometer and bending beam rheometer. The results have indicated that the polymer modified asphalt binders have lower penetration and higher softening point than neat asphalt indicating an improvement in stiffness of asphalt binder, and as a result, more resistant to rutting. Moreover, the dynamic shear rheometer results have shown that all modifiers used in this study improved the binder properties and satisfied the Superpave specifications except SBS KTR401 which failed to satisfy the rutting parameter (G*/sinδ).

Keywords: polymer modified asphalt, rheological properties, SBS, crumb rubber, EE-2

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Authors: Yaniv Knop, Alva Peled

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Over the past few years there has been a growing interest in the development of Portland Composite Cement, by partial replacement of the clinker with mineral additives. The motivations to reduce the clinker content are threefold: (1) Ecological - due to lower emission of CO2 to the atmosphere; (2) Economical - due to cost reduction; and (3) Scientific\Technology – improvement of performances. Among the mineral additives being used and investigated, limestone is one of the most attractive, as it is considered natural, available, and with low cost. The goal of the research is to develop green cement, by partial replacement of the clinker with limestone powder while improving the performances of the cement paste. This work studied blended cements with three limestone powder particle diameters: smaller than, larger than, and similarly sized to the clinker particle. Blended cement with limestone consisting of one particle size distribution and limestone consisting of a combination of several particle sizes were studied and compared in terms of hydration rate, hydration degree, and water demand to achieve normal consistency. The performances of these systems were also compared with that of the original cement (without added limestone). It was found that the ability to replace an active material with an inert additive, while achieving improved performances, can be obtained by increasing the packing density of the cement-based particles. This may be achieved by replacing the clinker with limestone powders having a combination of several different particle size distributions. Mathematical and physical models were developed to simulate the setting history from initial to final setting time and to predict the packing density of blended cement with limestone having different sizes and various contents. Besides the effect of limestone, as inert additive, on the packing density of the blended cement, the influence of the limestone particle size on three different chemical reactions were studied; hydration of the cement, carbonation of the calcium hydroxide and the reactivity of the limestone with the hydration reaction products. The main results and developments will be presented.

Keywords: packing density, hydration degree, limestone, blended cement

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Authors: Jeonghwan Jeon

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With the advent of IPTV in the fierce competition with existing broadcasting system, it is emerged as an important issue to predict how much the adoption of IPTV service will be. This paper aims to suggest a prediction model for adopting IPTV using classification and Ranking Belief Simplex (CaRBS). A simplex plot method of representing data allows a clear visual representation to the degree of interaction of the support from the variables to the prediction of the objects. CaRBS is applied to the survey data on the IPTV adoption.

Keywords: prediction, adoption, IPTV, CaRBS

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Authors: Ramin Zargarbashi, Hamid Rabie, Behnam Panjavi, Hooman Kamran, Seyedarad Mosalamiaghili, Zohre Erfani, Seyed Peyman Mirghaderi, Maryam Salimi

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Background: Posterior shoulder dislocation is one of the disabling complications of brachial plexus birth injury (BPBI), and various treatment options, including capsule and surrounding muscles release for open reduction, humeral derotational osteotomy, and tendon transfers, have been recommended to manage it. In the present study, we aimed to determine the clinical outcome of open reduction with soft tissue release, tendon transfer, and glenoid osteotomy inpatients with BPBI and posterior shoulder dislocation or subluxation. Methods: From 2018 to 2020, 33 patients that underwent open reduction, glenoid osteotomy, and tendon transfer were included. The glenohumeral deformity was classified according to the Waters radiographic classification. Functional assessment was performed using the Mallet grading system before and at least two years after the surgery. Results: The patients were monitored for 26.88± 5.47 months. Their average age was 27.5±14 months. Significant improvement was seen in the overall Mallet score (from 13.5 to 18.91 points) and its segments, including hand to mouth, hand to the neck, global abduction, global external rotation, abduction degree, and external rotation degree. Hand-to-back score and the presence of trumpet sign were significantly decreased in the post-operation phase (all p values<0.001). The above-mentioned variables significantly changed for both infantile and non-infantile dislocations. Conclusion: Our study demonstrated that open reduction along with glenoid osteotomy improves retroversion, and muscle strengthening with different muscle transfers is an effective technique for BPBI.

Keywords: birth injuries, nerve injury, brachial plexus birth palsy, Erb palsy, tendon transfer

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Authors: Helmi Temimi

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In this paper, we study the super-convergence properties of the discontinuous Galerkin (DG) method applied to one-dimensional mth-order ordinary differential equations without introducing auxiliary variables. We found that nth−derivative of the DG solution exhibits an optimal O (hp+1−n) convergence rates in the L2-norm when p-degree piecewise polynomials with p≥1 are used. We further found that the odd-derivatives and the even derivatives are super convergent, respectively, at the upwind and downwind endpoints.

Keywords: discontinuous, galerkin, superconvergence, higherorder, error, estimates

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Authors: P. Zamani, S. Mohajerzadeh, R. Masoudinejad, K. Farhangdoost

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The riveting process is one of the important ways to keep fastening the lap joints in aircraft structures. Failure of aircraft lap joints directly depends on the stress field in the joint. An important application of riveting process is in the construction of aircraft fuselage structures. In this paper, a 3D finite element method is carried out in order to optimize residual stress field in a riveted lap joint and also to estimate its fatigue life. In continue, a number of experiments are designed and analyzed using design of experiments (DOE). Then, Taguchi method is used to select an optimized case between different levels of each factor. Besides that, the factor which affects the most on residual stress field is investigated. Such optimized case provides the maximum residual stress field. Fatigue life of the optimized joint is estimated by Paris-Erdogan law. Stress intensity factors (SIFs) are calculated using both finite element analysis and experimental formula. In addition, the effect of residual stress field, geometry, and secondary bending are considered in SIF calculation. A good agreement is found between results of such methods. Comparison between optimized fatigue life and fatigue life of other joints has shown an improvement in the joint’s life.

Keywords: fatigue life, residual stress, riveting process, stress intensity factor, Taguchi method

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Authors: Sarai Alvarado Pineda, Ricardo Maldonado Soto

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The acquisition of Verb Particle Constructions is a challenge for Spanish speakers learning English. The acquisition is particularly difficult for speakers of languages with no verb particle constructions. The purpose of the current study is to define the procedural steps in the acquisition of constructions with the particle on. There are three outstanding meanings for the particle on; Surface: The movie is based on a true story, Activation: John turn on the light, Continuity: The band played on all night. The central aim of this study is to measure how Mexican Spanish participants respond to both the three meanings mentioned above and the degree of meaning transparency/opacity of on verb particle constructions. Forty Mexican Spanish learners of English (20 basic and 20 advanced) are compared against a control group of 20 American native English speakers through a reaction time test (PsychoPy2 2015). The participants were asked to discriminate 90 items based on their knowledge of these constructions. There are 30 items per meaning divided into two groups of transparent and opaque meaning. Results revealed three major findings: Advanced students have a reaction time similar to that of native speakers (advanced 4.5s versus native 3.7s), while students with a lower level of English proficiency, show a high reaction time (7s). Likewise, there is a shorter reaction time in constructions with lower opacity in the three groups of participants, with differences between each level (basic 6.7s, advanced 4.3s, and native 3.4s). Finally, a difference in reaction time can be identified according to the meaning provided by the construction. The reaction time for the activation category (5.27s) is greater than continuity (5.04s), and this category is also slower than the surface (4.94s). The study shows that the level of sensitivity of English learners increases significantly aiming towards native speaker patterns as determined by the level of transparency of meaning of each construction as well as the degree of entrenchment of each constructional meaning.

Keywords: meaning of the particle, opacity, reaction time, verb particle constructions

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Authors: Keunhong Chae, Seokho Yoon

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Recently, the global navigation satellite system (GNSS) such as Galileo and GPS is employing more satellites to provide a higher degree of accuracy for the location service, thus calling for a more efficient signaling scheme among the satellites used in the overall GNSS network. In that the network throughput is improved, the spatial diversity can be one of the efficient signaling schemes; however, it requires multiple antenna that could cause a significant increase in the complexity of the GNSS. Thus, a diversity scheme called the cooperative signaling was proposed, where the virtual multiple-input multiple-output (MIMO) signaling is realized with using only a single antenna in the transmit satellite of interest and with modeling the neighboring satellites as relay nodes. The main drawback of the cooperative signaling is that the relay nodes receive the transmitted signal at different time instants, i.e., they operate in an asynchronous way, and thus, the overall performance of the GNSS network could degrade severely. To tackle the problem, several modified cooperative signaling schemes were proposed; however, all of them are difficult to implement due to a signal decoding at the relay nodes. Although the implementation at the relay nodes could be simpler to some degree by employing the time-reversal and conjugation operations instead of the signal decoding, it would be more efficient if we could implement the operations of the relay nodes at the source node having more resources than the relay nodes. So, in this paper, we propose a novel cooperative signaling scheme, where the data signals are combined in a unique way at the source node, thus obviating the need of the complex operations such as signal decoding, time-reversal and conjugation at the relay nodes. The numerical results confirm that the proposed scheme provides the same performance in the cooperative diversity and the bit error rate (BER) as the conventional scheme, while reducing the complexity at the relay nodes significantly. Acknowledgment: This work was supported by the National GNSS Research Center program of Defense Acquisition Program Administration and Agency for Defense Development.

Keywords: global navigation satellite network, cooperative signaling, data combining, nodes

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Authors: Pallab Datta, Jyotirmoy Chatterjee, Santanu Dhara

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Over the past few years, phosphorous containing polymers have received widespread attention for applications such as high performance optical fibers, flame retardant materials, drug delivery and tissue engineering. Being pentavalent, phosphorous can exist in different chemical environments in these polymers which increase their versatility. In human biochemistry, phosphorous based compounds exert their functions both in soluble and insoluble form occurring as inorganic or as organophosphorous compounds. Specifically in case of biomacromolecules, phosphates are critical for functions of DNA, ATP, phosphoproteins, phospholipids, phosphoglycans and several coenzymes. Inspired by the role of phosphorous in functional biomacromolecules, design and synthesis of biomimetic materials are thus carried out by several authors to study macromolecular function or as substitutes in clinical tissue regeneration conditions. In addition, many regulatory signals of the body are controlled by phoshphorylation of key proteins present either in form of growth factors or matrix-bound scaffold proteins. This inspires works on synthesis of phospho-peptidomimetic amino acids for understanding key signaling pathways and this is extended to obtain molecules with potentially useful biological properties. Apart from above applications, phosphate groups bound to polymer backbones have also been demonstrated to improve function of osteoblast cells and augment performance of bone grafts. Despite the advantages of phosphate grafting, however, there is limited understanding on effect of degree of phosphorylation on macromolecular physicochemical and/or biological properties. Such investigations are necessary to effectively translate knowledge of macromolecular biochemistry into relevant clinical products since they directly influence processability of these polymers into suitable scaffold structures and control subsequent biological response. Amongst various techniques for fabrication of biomimetic scaffolds, nanofibrous scaffolds fabricated by electrospinning technique offer some special advantages in resembling the attributes of natural extracellular matrix. Understanding changes in physico-chemical properties of polymers as function of phosphorylation is therefore going to be crucial in development of nanofiber scaffolds based on phosphorylated polymers. The aim of the present work is to investigate the effect of phosphorous grafting on the electrospinning behavior of polymers with aim to obtain biomaterials for bone regeneration applications. For this purpose, phosphorylated derivatives of two polymers of widely different electrospinning behaviors were selected as starting materials. Poly(vinyl alcohol) is a conveniently electrospinnable polymer at different conditions and concentrations. On the other hand, electrospinning of chitosan backbone based polymers have been viewed as a critical challenge. The phosphorylated derivatives of these polymers were synthesized, characterized and electrospinning behavior of various solutions containing these derivatives was compared with electrospinning of pure poly (vinyl alcohol). In PVA, phosphorylation adversely impacted electrospinnability while in NMPC, higher phosphate content widened concentration range for nanofiber formation. Culture of MG-63 cells on electrospun nanofibers, revealed that degree of phosphate modification of a polymer significantly improves cell adhesion or osteoblast function of cultured cells. It is concluded that improvement of cell response parameters of nanofiber scaffolds can be attained as a function of controlled degree of phosphate grafting in polymeric biomaterials with implications for bone tissue engineering applications.

Keywords: bone regeneration, chitosan, electrospinning, phosphorylation

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Authors: Shivi Rastogi, Suman Pant

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Khadi is an Indian fabric and also known by another name “Khaddar”. During pre-independence era, the movement of khadi manufacturing gained momentum. Over the years, khadi fabrics that were generally considered as the “second skin” of the Swadesh revolutionists changed its uniqueness. It underwent a metamorphosis from that of a patriot’s fabric, and a farmer’s apparel, to become a “fashion fabric”. Drape of garment is governed by draping quality of fabric used. Drape is an essential parameter to decide both appearance and handle of fabric. It is also a secondary determinant of fabric mechanical properties as influenced by the low stress properties, like bending length, formability, tensile and shear properties and compressibility of the fabric. In finishing, fabric is treated to add something to coat the fabric or fiber and thereby temporarily or permanently fix. Film forming agents such as thermoplastic and thermosetting resins and other surface deposits alter hand. In this study, resins were used to modify fabric hand. Three types of resins have been applied on the khadi fabric at three concentration. The effect of these finishes on drapeability, crease recovery, stiffness, tearing strength and smoothness of khadi fabrics were assessed. Silicone gave good results in imparting properties specially drape, smoothness and softness and hand of cotton and khadi fabric. KES result also showed that silicone treated samples enhanced THV rating amongst all treated samples when compared to the control fabric.

Keywords: crease recovery, drapeability, KES, silicone, THV

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Authors: Nadezhda F. Mikahailova, Margarita E. Fattakhova, Mirgarita A. Mironova, Ekaterina V. Vyacheslavova, Vladimir A. Mikahailov

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Stigma is a significant obstacle to the successful adaptation of deaf students to the conditions of an educational institution, especially for those who study in inclusion. The aim of the study was to identify the spheres of life which are the most significant for developing of the stigma of deaf students; to assess the influence of factors associated with deafness on the degree of their self-stigmatization (time and degree of hearing loss, type of education - inclusion / differentiation) and to find out who is more prone to stigma - which characteristics of personality, identity, mental health and coping are specific for those deaf who demonstrates stigmatizing attitudes. The study involved 154 deaf and hard-of-hearing students (85 male and 69 female) aged from 18 to 45 years - 28 students of the Herzen State Pedagogical University (St. Petersburg), who study in inclusion, 108 students of the National Research Technological University and 18 students of the Aviation Technical College (Kazan) - students in groups with a sign language interpreter. We used the following methods: modified questionnaire 'Self-assessment and coping strategies' (Jambor & Elliot, 2005), Scale of self-esteem (Rosenberg et al, 1995), 'Big-Five' (Costa&McCrae, 1997), TRF (Becker, 1989), WCQ (Lazarus & Folkman, 1988), self-stigma scale (Mikhailov, 2008). The severity of self-stigmatization of deaf and hard of hearing students was determined by the degree of deafness and the time they live with hearing loss, learning conditions, the type of self-identification (acculturation), personality traits, and the specifics of coping behavior. Persons with congenital hearing loss more often noted a benevolent and sympathetic attitude towards them on the part of the hearers and less often, due to deafness, limited themselves to visiting public places than late deaf people, which indicates 'get rid of' the experience of their defect and normalization of the state. Students studying in conditions of inclusion more often noted the dismissive attitude of society towards deaf people. Individuals with mild to moderate hearing loss were more likely to fear marriage and childbearing because of their deafness than students with profound hearing loss. Those who considered themselves disabled (49% of all respondents) were more inclined to cope with seeking social support and less used 'distancing' coping. Those who believed that their quality of life and social opportunities were most influenced by the attitude of society towards the deaf (39%) were distinguished by a less pronounced sense of self-worth, a desire for autonomy, and frequent usage of 'avoidance' coping strategies. 36.4% of the respondents noted that there have been situations in their lives when people learned that they are deaf, began to treat them worse. These respondents had predominantly deaf acculturation, but more often, they used 'bicultural skills,' specific coping for the deaf, and had a lower level of extraversion and emotional stability. 31.2% of the respondents tried to hide from others that they have hearing problems. They considered themselves to be in a culture of hearing, used coping strategies 'bicultural skills,' and had lower levels of extraversion, cooperation, and emotional stability. Acknowledgment: Supported by the RFBR № 19-013-0040

Keywords: acculturation, coping, deafness, stigmatization

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Authors: Ji Un Shin, Wei Mao, Hyuk Sang Yoo

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Electrospinning is a versatile tool for fabricating nano-structured polymeric materials. Gelatin hydrogels are considered to be a good material for cell cultivation because of high water swellability as well as good biocompatibility. Three-dimensional (3-D) cell cultivation is a desirable method of cell cultivation for preparing tissues and organs because cell-to-cell interactions or cell-to-matrix interactions can be much enhanced through this approach. For this reason, hydrogels were widely employed as tissue scaffolds because they can support cultivating cells and tissue in multi-dimensions. Major disadvantages of hydrogel-based cell cultivation include low mechanical properties, lack of topography, which should be enhanced for successful tissue engineering. Herein we surface-immobilized gelatin on the surface of nanofibrous matrix for 3-D cell cultivation in topographical cues added environments. Electrospun nanofibers were electrospun with injection of poly(caprolactone) through a single nozzle syringe. Electrospun meshes were then chopped up with a high speed grinder to fine powders. This was hydrolyzed in optimized concentration of sodium hydroxide solution from 1 to 6 hours and harvested by centrifugation. The freeze-dried powders were examined by scanning electron microscopy (SEM) for revealing the morphology and fibrilar shaped with a length of ca. 20um was observed. This was subsequently immersed in gelatin solution for surface-coating of gelatin, where the process repeated up to 10 times for obtaining desirable coating of gelatin on the surface. Gelatin-coated nanofibrils showed high waterswellability in comparison to the unmodified nanofibrils, and this enabled good dispersion properties of the modified nanofibrils in aqueous phase. The degree of water-swellability was increased as the coating numbers of gelatin increased, however, it did not any meaning result after 10 times of gelatin coating process. Thus, by adjusting the gelatin coating times, we could successfully control the degree of hydrophilicity and water-swellability of nanofibrils.

Keywords: nano, fiber, cell, tissue

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Authors: Ali Raza, Rūta Rimašauskienė

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In the current work, the fused deposition modelling (FDM) technique is used to manufacture PLA reinforced with carbon fibre composite structures with two unique layer patterns, 0°\0° and 0°\90°. The purpose of the study is to investigate the dynamic characteristics of each fabricated composite structure. The Macro Fiber Composite (MFC) is embedded with 0°/0° and 0°/90° structures to investigate the effect of an MFC (M8507-P2 type) patch on vibration amplitude suppression under dynamic loading circumstances. First, modal analysis testing was performed using a Polytec 3D laser vibrometer to identify bending mode shapes, natural frequencies, and vibration amplitudes at the corresponding natural frequencies. To determine the stiffness of each structure, several loads were applied at the free end of the structure, and the deformation was recorded using a laser displacement sensor. The findings confirm that a structure with 0°\0° layers pattern was found to have more stiffness compared to a 0°\90° structure. The maximum amplitude suppression in each structure was measured using a laser displacement sensor at the first resonant frequency when the control voltage signal with optimal phase was applied to the MFC. The results confirm that the 0°/0° pattern's structure exhibits a higher displacement reduction than the 0°/90° pattern. Moreover, stiffer structures have been found to perform amplitude suppression more effectively.

Keywords: carbon fibre composite, MFC, modal analysis stiffness, stiffness

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Authors: Carlos Cuenca, Diego Sarzosa

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Ductile fracture occurs by the mechanism of void nucleation, void growth and coalescence. Potential sites for initiation are second phase particles or non-metallic inclusions. Modelling of ductile damage at the microscopic level is very difficult and complex task for engineers. Therefore, conservative predictions of ductile failure using simple models are necessary during the design and optimization of critical structures like pressure vessels and pipelines. Nowadays, it is well known that the initiation phase is strongly influenced by the stress triaxiality and plastic deformation at the microscopic level. Thus, a simple model used to study the ductile failure under multiaxial stress condition is the Stress Modified Critical Strain (SMCS) approach. Ductile rupture has been study for a structural steel under different stress triaxiality conditions using the SMCS method. Experimental tests are carried out to characterize the relation between stress triaxiality and equivalent plastic strain by notched round bars. After calibration of the plasticity and damage properties, predictions are made for low constraint bending specimens with and without side grooves. Stress/strain fields evolution are compared between the different geometries. Advantages and disadvantages of the SMCS methodology are discussed.

Keywords: damage, SMSC, SEB, steel, failure

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Authors: Mezidi Amar

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In this research work, crack propagation at the interface of a composite beam is considered. The behavior of composite beams (CB) depends upon a law based on relationship between tangential or normal efforts with inelastic propagation. Throughout this study, composite beams are classified like composite beams with partial connection or sandwich beams of three layers. These structural systems are controlled by the same nature of differential equations regarding their behavior in the plane, as well as out-of-plane. Multi-layer elements with partial connection are typically met in the field of timber construction where the elements are assembled by joining. The formalism of the behavior in the plane and out-of-plane of these composite beams is obtained and their results concerning the engineering aspect or simple of interpretation are proposed for the case of composite beams made up of rectangular section and simply supported section. An apparent analytical peculiarity or paradox in the bending behavior of elastic–composite beams with interlayer slip, sandwich beam or other similar problems subjected to boundary moments exists. For a fully composite beam subjected to end moments, the partial composite model will render a non-vanishing uniform value for the normal force in the individual subelement. Obtained results are similar to those for the case of vibrations in the plane as well for the composite beams as for the sandwich beams where eigen-frequencies increase with related rigidity.

Keywords: composite beam, behaviour, interface, deflection, propagation

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Authors: Nadjoua Bourmatte, Hacène Houari

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Glass has been indispensable to men’s life due to its properties, including pliability to take any shape with ease, bright surface, resistance to abrasion, reasonable safety and durability. Waste glass creates serious environmental problems, mainly due to the inconsistency of waste glass streams. With increasing environmental pressure to reduce solid waste and to recycle as much as possible, the concrete industry has adopted a number of methods to achieve this goal. The object of this research work is to study the effect of using recycled glass waste, as a partial replacement of fine aggregate, on the fresh and hardened properties of concrete. Recycled glass was used to replace fine aggregate in proportions of 0%, 25% and 50%. We could observe that the Glass waste aggregates are lighter than natural aggregates and they show a very low water absorption. The experimental results showed that the slump flow increased with the increase of recycled glass content. On the other hand, the compressive strength and tensile strength of recycled glass mixtures decreased with the increase in the recycled glass content. The results showed that recycled glass aggregate can successfully be used with limited level for producing concrete. The standard sand was substituted with aggregates based on glass waste for manufacturing mortars, Mortar based on glass shows a compressive strength and low bending with a 1/2 ratio with control mortar strength.

Keywords: concrete, environment, glass waste, recycling

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Authors: Maged Syed Ahamd, Manal Mohamed Yasser, Essam Sholkamy

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In this paper, we reported that selenium (Se) nanoparticles were firstly biosynthesized with a simple and eco-friendly biological method. Their shape, size, FTIR (Fourier Transform Infrared spectroscopy), UV–vis spectra, TEM (Transmission Electron Microscopy) images and EDS (Energy Dispersive Spectroscopy) pattern have been analyzed. TEM analyses of the samples obtained at different stages indicated that the formation of these Se nanostructures was governed by an incubation time (12- 24- 48 hours). The Se nanoparticles were initially generated and then would transform into crystal seeds for the subsequent growth of nanowires; however obtaining stable Se nanowire with a diameter of about 15-100 nm. EDS shows that Se nanoparticles are entirely pure. The IR spectra showed the peaks at 550 cm-1, 1635 cm-1, 1994 cm-1 and 3430 cm-1 correspond to the presence of Se-O bending and stretching vibrations. The concentrations of Se-NPs (0, 1, 2, 5 µg/ml) did not give significantly effect on both two cell lines while the highest concentrations (10- 100 µg/ml gave significantly effects on them. The lethal dose (ID50%) of Se-NPs on Hep2 G and MCF-7 cells was obtained at 75.96 and 61.86 µg/ml, respectively. Results showed that Se nanoparticles as anticancer agent against MCF-7 cells were more effective than Hep2 G cells. Our results suggest that Se-NPs may be a candidate for further evaluation as a chemotherapeutic agent for breast and liver cancers.

Keywords: selenium nanoparticle, Streptomyces bikiniensis, nanowires, chemotherapeutic agent

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Authors: Ayo Osisanya, Promise Ebuka Okonkwo

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Reduced hearing sensitivity among the elderly has been attributed to some risk factors and influence of age-related degenerative conditions such as diabetes, cardiovascular disease, Alzheimer’s disease, bipolar disorder, and hypertension. Hearing loss; especially the age-related type (presbycusis), has been reported as one of the global burden affecting the general well-being and quality of life of the elderly with hypertension. Thus, hearing loss has been observed to be associated with hypertension and functional decline in elderly, as this condition makes them experience poor communication, fatigue, reduced social functions, mood-swing, and withdrawal syndrome. Emerging research outcomes indicate a strong relationship between hypertension and reduced auditory performance among the elderly. Therefore, this study determined the prevalence, types, and patterns of hearing loss associated with hypertension, with a bid to suggesting comprehensive management strategies and a model of creating awareness towards promoting good healthy living among the elderly in Nigeria. One hundred and seventy-two elderly, aged 65–85 with hypertension were purposively selected from patients undergoing treatment for hypertension in some tertiary hospitals in southwest Nigeria for the study. Participants were suggested to Pure-Tone Audiometry (PTA) through the use of Maico 53 Diagnostic Audiometer to determine the degree, types ad patterns of hearing loss among the elderly with hypertension. Results showed that 148 (86.05%) elderly with hypertension presented with different degrees, types, and patterns of hearing loss. Out of this number, 123 (83.11%) presented with bilateral hearing loss, while 25 (16.89%) had unilateral hearing loss. Degree of hearing loss, 74 moderate hearing loss, 118 moderately severe and 50 severe hearing loss. 36% of the hearing loss appeared as flat audiometric configuration, 24% were slopping, 19% were rising, while 21% were tough-shaped audiometric configurations. The findings showed high prevalence of hearing loss among the elderly with hypertension in Southwest, Nigeria. Based on the findings, management of elderly with hypertension should include regular audiological rehabilitation and total adherence to hearing conservation principles, otological management, regulation of blood pressure and adequate counselling / follow-up services.

Keywords: auditory performance, elderly, hearing loss, hypertension

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Authors: K. Kamal

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Structural sandwich panels with core of Advanced Composites Laminates l Honeycombs / PU-foams are used in aerospace applications and are also fabricated for use now in some civil engineering applications. An all Advanced Composites Foot Over Bridge (FOB) system, designed and developed for pedestrian traffic is one such application earlier, may be cited as an example here. During development stage of this FoB, a profile of its decks was then spurred as a single corrugate sheet core sandwiched between two Glass Fibre Reinforced Plastics(GFRP) flat laminates. Once successfully fabricated and used, these decks did prove suitable also to form other structure on assembly, such as, erecting temporary shelters. Such corrugated sheet core profile sandwiched panels were then also tried using the construction materials but any conventional method of construction only posed certain difficulties in achieving the required core profile monolithically within the sandwiched slabs and hence it was then abended. Such monolithic construction was, however, subsequently eased out on demonstration by dispensing building materials mix through a suitably designed multi-dispenser system attached to a 3D Printer. This study conducted at lab level was thus reported earlier and it did include the fabrication of a 3D printer in-house first as ‘3DcMP’ as well as on its functional operation, some required sandwich core profiles also been 3D-printed out producing panels hardware. Once a number of these sandwich panels in single corrugated sheet core monolithically printed out, panels were subjected to load test in an experimental set up as also their structural behavior was studied analytically, and subsequently, these results were correlated as reported in the literature. In achieving the required more depths and also to exhibit further the stronger and creating sandwiched decks of better structural and mechanical behavior, further more complex core configuration such as stack corrugate sheets core with a flat mid plane was felt to be the better sandwiched core. Such profile remained as an outcome that turns out merely on stacking of two separately printed out monolithic units of single corrugated sheet core developed earlier as above and bonded them together initially, maintaining a different orientation. For any required sequential understanding of the structural behavior of any such complex profile core sandwiched decks with special emphasis to study of the effect in the variation of corrugation orientation in each distinct tire in this core, it obviously calls for an analytical study first. The rectangular,simply supported decks have therefore been considered for analysis adopting the ‘Advanced Composite Technology(ACT), some numerical results along with some fruitful findings were obtained and these are all presented here in this paper. From this numerical result, it has been observed that a mid flat layer which eventually get created monolethically itself, in addition to eliminating the bonding process in development, has been found to offer more effective bending resistance by such decks subjected to UDL over them. This is understood to have resulted here since the existence of a required shear resistance layer at the mid of the core in this profile, unlike other bending elements. As an addendum to all such efforts made as covered above and was published earlier, this unique stack corrugate sheet core profile sandwiched structural decks, monolithically construction with ease at the site itself, has been printed out from a 3D Printer. On employing 3DcMP and using some innovative building construction materials, holds the future promises of such research & development works since all those several aspects of a 3D printing in construction are now included such as reduction in the required construction time, offering cost effective solutions with freedom in design of any such complex shapes thus can widely now be realized by the modern construction industry.

Keywords: advance composite technology(ACT), corrugated laminates, 3DcMP, foot over bridge (FOB), sandwiched deck units

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Authors: Naiara Ozamiz Etcebarria, Sonia Ruiz De Azua Garcia, Agurtzane Ortiz Jauregi, Virginia Guillen Cañas

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Introduction: The most relevant competencies of a health professional are an adequate communication capacity, which will influence the satisfaction of professionals and patients, therapeutic compliance, conflict prevention, clinical outcomes´ improvement and efficiency of health services. The ability of Active listening , empathy, assertiveness and social skills, are important abilities to develop in all professions in which there is a relationship with other people. In the field of health, it is even more important to have adequate qualities so that the treatment with the patient will be adequate and satisfactory. We conducted a research with students of third year in the Degree of Medicine with the objectives: - to know how the active listening, empathy, assertiveness and social skills of students are. - to know if there are differences according to different demographic variables, such as sex, language, age, number of siblings and interest in the subject. Material and Methods: The students of the Third year in the Degree of Medicine (N = 212) participated voluntarily. Sociodemographic data were collected. Descriptive and comparative analysis of the averages of the students with respect to active listening, empathy, assertiveness and social skills were performed. Once the questionnaires were collected, they were entered into the SPSS 21 database. Four communicational aspects were evaluated: The active listening questionnaire, the TECA empathy questionnaire, the ACDA questionnaire and the EHS questionnaire Social Skills Scale. The active listening questionnaire assesses these factors: Listening without interruption and less contradiction, Listening with 100% attention, Listening beyond words, Listening encouraging the other to go deeper. The TECA questionnaire of cognitive and affective empathy evaluates: Adoption of perspectives, Emotional Comprehension, Emphasizing stress, Empathic joy. The EHS questionnaire Social Skills Scale: Self-expression in social situations, Defending one's own rights as a consumer, Expressing anger or dissatisfaction, Refusing to do and cutting interactions off, Making requests, Initiating positive interactions with the other sex. The ACDA questionnaire Assertiveness Assessment Scale evaluates self-assertiveness and heteroaservitivity. Applicability: To train these skills is so important for clinical practice of medical students and these capabilities that can be measured in a longitudinal way time. Ethical-legal aspects: The data were anonymous. The study was approved by the Ethics Committee. Results: The students of the Third year in the Degree of Medicine (34.4% Basque speakers and 65.6% Spanish speakers) with average age 20.93, (27.8% men and 72.2% women). There are no differences in social skills between men and women. The Basque speaker students of are more heteroactive (ACDA) than Spanish students. Active listening has a high correlation with social skills, especially with self-expression in social situations. Listening without interruption has a high correlation with self-expression in social situations and initiating positive interactions with the opposite sex. Adoption of perspectives presents a high correlation with auto- assertiveness. Emotional understanding presents a high correlation with positive interactions with the opposite sex. Empathic joy correlates with self-assertiveness, self-expression in social situations, and initiating positive interactions with the opposite sex.

Keywords: active listening, assertiveness, communicational skills, empathy, students of medicine

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Authors: T. R. Sreeram, S. Natarajan, C. Jena

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Civil engineering construction is a network of tasks involving varying degree of complexity and streamlining, and standardization is the only way to establish a systemic approach to design. While there are off the shelf tools such as AutoCAD that play a role in the realization of design, the repeatable process in which these tools are deployed often is ignored. The present paper addresses this challenge through a sustainable design process and effective standardizations at all stages in the design workflow. The same is demonstrated through a case study in the context of construction, and further improvement points are highlighted.

Keywords: syste, lean, value stream, process improvement

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Authors: Shimaa A. Higazy, Mohamed S. Selim, Olfat E. El-Azabawy, Abeer A. Hassan

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We designed novel epoxy/graphitic carbon nitride (g-C₃N₄) nanocomposite materials as suitable surface coatings. g-C₃N₄ nanosheets were facilely prepared and dispersed in the epoxy resin via solution casting. This research focuses on the mechanical and anticorrosion properties of g-C₃N₄ nanofiller reinforced epoxy nanocomposites. The structures, sizes, and morphologies of designed polymeric nanocomposites and nanofillers were elucidated using various techniques such as FT-IR, NMR, FE-TEM, FE-SEM. The developed nanocomposite was applied as a surface coating by air-assisted spray method. The structure-property relationship was studied for different concentrations of nanofiller in the epoxy matrix. The anticorrosive properties were studied via electrochemical experiments, including potentiodynamic polarization, electrochemical impedance, and open-circuit potential analyses, as well as salt spray test. Mechanical durability was assessed by various methods, such as impact, T-bending, and crosscut tests. Surface heterogeneity, elasticity, and corrosion-resistance features are among the merits of developed composite. The highest improvement was achieved with well dispersion of g-C₃N₄ sheets fillers. This fascinating epoxy nanostructured coating provides a promising anticorrosive coatings for a sustainable future environment.

Keywords: epoxy, nanocomposite, surface coating, anticorrosive properties, mechanical durability

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Authors: Eda Gök

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Peridynamics is a new modeling concept of non-local interactions for solid structures. The formulations of Peridynamic (PD) theory are based on integral equations rather than differential equations. Through, undefined equations of associated problems are avoided. PD theory might be defined as continuum version of molecular dynamics. The medium is usually modeled with mass particles bonded together. Particles interact with each other directly across finite distances through central forces named as bonds. The main assumption of this theory is that the body is composed of material points which interact with other material points within a finite distance. Although, PD theory developed for discontinuities, it gives good results for structures which have no discontinuities. In this paper, displacement control of the isotropic plate under the effect of tensile and bending loading has been investigated by means of PD theory. A MATLAB code is generated to create PD bonds and corresponding surface correction factors. Using generated MATLAB code the geometry of the specimen is generated, and the code is implemented in Finite Element Software. The results obtained from non-local continuum theory are compared with the Finite Element Analysis results and analytical solution. The results show good agreement.

Keywords: non-local continuum mechanics, peridynamic theory, solid structures, tensile loading, flexural loading

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Authors: A. P. Srivastava, D. Srivastava, D. J. Browne

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Relaxation dynamics of Zr44Cu40Al8Ag8 bulk metallic glass (BMG) has been probed using dynamic mechanical analyzer. The BMG sample was casted in the form of a plate of dimension 55 mm x 40 mm x 3 mm using tilt casting technique. X-ray diffraction and transmission electron microscope have been used for the microstructural characterization of as-cast BMG. For the mechanical spectroscopy study, samples in the form of a bar of size 55 mm X 2 mm X 3 mm were machined from the BMG plate. The mechanical spectroscopy was performed on dynamic mechanical analyzer (DMA) by 50 mm 3-point bending method in a nitrogen atmosphere. It was observed that two glass transition process were competing in supercooled liquid region around temperature 390°C and 430°C. The supercooled liquid state was completely characterized using DMA and differential scanning calorimeter (DSC). In addition to the main α-relaxation process, presence of β relaxation process around temperature 360°C; below the glass transition temperature was also observed. The β relaxation process could be described by Arrhenius law with the activation energy of 160 kJ/mole. The volume of the flow unit associated with this relaxation process has been estimated. The results from DMA study has been used to characterize the shear transformation zone in terms of activation volume and size. High fragility parameter value of 34 and higher activation volume indicates that this alloy could show good plasticity in supercooled liquid region. The possible mechanism for the relaxation processes has been discussed.

Keywords: DMA, glass transition, metallic glass, thermoplastic forming

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