Search results for: critical Rayleigh number

Authors: Shuaibu Hassan Usman, Ishaq Oyebisi Oyefolahan

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This study was aimed to explore the latent factors in the web 2.0 enabled knowledge sharing practices instrument. Seven latent factors were identified through a factor analysis with orthogonal rotation and interpreted based on simple structure convergence, item loadings, and analytical statistics. The number of factors retains was based on the analysis of Kaiser Normalization criteria and Scree plot. The reliability tests revealed a satisfactory reliability scores on each of the seven latent factors of the web 2.0 enabled knowledge sharing practices. Limitation, conclusion, and future work of this study were also discussed.

Keywords: factor analysis, latent factors, knowledge sharing practices, students, web 2.0 enabled

Procedia PDF Downloads 428

Authors: Tasleem Zafar, Jiwan Sidhu

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Introduction: Chickpea flour is known to offer many benefits to diabetic persons, especially in maintaining their blood sugar levels in the acceptable range. Under this project we have studied the chemical composition and antioxidant capacity of white flour (WF), whole wheat flour (WWF) and chickpea flour (BF), in addition to the effect of replacement of WF and WWF with BF on the rheological characteristics of these flour blends, with the ultimate objective of producing acceptable quality flat as well as pan-bread for the diabetic consumers. Methods: WF and WWF were replaced with BF ranging from 0 to 40%, to investigate its effect on the rheological properties and functionality of blended flour dough using farinograph, viscoamylograph, mixograph and falling number apparatus as per the AACC standard methods. Texture Profile Analysis (TPA) was carried on the WF, WWF, and their blends with BF using Stable Micro System Texture Analyzer. Effect of certain additives, such as freeze-dried amla fruit powder (Phyllanthus emblica L.), guar gum, and xanthan gum on the dough rheological properties were also studied. Results: Freeze-dried amla fruit powder was found to be very rich in ascorbic acid and other phenolics having higher antioxidant activity. A decreased farinograph water absorption, increased dough development time, higher mixing tolerance index (i.e., weakening of dough), decreased resistance to extension, lower ratio numbers were obtained when the replacement with BF was increased from 0 to 40%. The BF gave lower peak viscosity, lower paste breakdown, and lower setback values when compared with WF. The falling number values were significantly lower in WWF (meaning higher α-amylase activity) than both the WF and BF. Texture Profile Analysis (TPA) carried on the WF, WWF, and their blends with BF showed significant variations in hardness and compressibility values, dough becoming less hard and less compressible when the replacement of WF and WWF with BF was increased from 0 to 40%. Conclusions: To overcome the deleterious effects of adding BF to WF and WWF on the rheological properties will be an interesting challenge when good quality pan bread and Arabic flatbread have to be commercially produced in a bakery. Use of freeze-dried amla fruit powder, guar gum, and xanthan gum did show some promise to improve the mixing characteristics of WF, WWF, and their blends with BF, and these additives are expected to be useful in producing an acceptable quality flat as well as pan-bread on a commercial scale.

Keywords: wheat flour, chickpea flour, amla fruit, rheology

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Authors: Alexander P. Smirnov, Sergey A. Matveev, Dmitry A. Zheltkov, Eugene E. Tyrtyshnikov

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We propose a new computational technique for multidimensional (multicomponent) Smoluchowski coagulation equation. Using low-rank approximations in Tensor Train format of both the solution and the coagulation kernel, we accelerate the classical finite-difference Runge-Kutta scheme keeping its level of accuracy. The complexity of the taken finite-difference scheme is reduced from O(N^2d) to O(d^2 N log N ), where N is the number of grid nodes and d is a dimensionality of the problem. The efficiency and the accuracy of the new method are demonstrated on concrete problem with known analytical solution.

Keywords: tensor train decomposition, multicomponent Smoluchowski equation, runge-kutta scheme, convolution

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Authors: Awad A. Younis, Elise Stronberg, Shifa Noor

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Malware attacks due to end-user vulnerabilities have been noticeably increased in the past few years. Investigating the factors that make an end-user vulnerable to those attacks is critical because they can be utilized to set up proactive strategies such as awareness and education to mitigate the impacts of those attacks. Some existing studies investigated demographic, behavioral, and cultural factors that make an end-user susceptible to malware attacks. However, it has been challenging to draw more general conclusions from individual studies due to the varieties in the type of end-users and different types of malware. Therefore, we conducted a systematic literature review (SLR) of the existing research for end-user susceptibility factors to malware attacks. The results showed while some demographic factors are mostly associated with malware infection regardless of the end users' type, age, and gender are not consistent among the same and different types of end-users. Besides, the association of culture and personality factors with malware infection are consistent in most of the selected studies and for all type of end-users. Moreover, malware infection varies based on age, geographic location, and host types. We propose that future studies should carefully take into consideration the type of end-users because different end users may be exposed to different threats or be targeted based on their user domains’ characteristics. Additionally, as different types of malware use different tactics to trick end-users, taking the malware types into consideration is important.

Keywords: cybersecurity, malware, end-users, demographics, personality, culture, systematic literature review

Procedia PDF Downloads 224

Authors: Sonia Amariei, Ionut Avramia, Florin Ursachi, Ancuta Chetrariu, Ancuta Petraru

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The food industry is one of the major generators of plastic waste derived from conventional synthetic petroleum-based polymers, which are non-biodegradable, used especially for packaging. These packaging materials, after the food is consumed, accumulate serious environmental concerns due to the materials but also to the organic residues that adhere to them. It is the concern of specialists, researchers to eliminate problems related to conventional materials that are not biodegradable or unnecessary plastic and replace them with biodegradable and edible materials, supporting the common effort to protect the environment. Even though environmental and health concerns will cause more consumers to switch to a plant-based diet, most people will continue to add more meat to their diet. The paper presents the possibility of replacing the polyethylene packaging from the surface of the trays for meat preparations with biodegradable packaging obtained from biopolymers. During the storage of meat products may occur deterioration by lipids oxidation and microbial spoilage, as well as the modification of the organoleptic characteristics. For this reason, different compositions of polymer mixtures and film conditions for obtaining must be studied to choose the best packaging material to achieve food safety. The compositions proposed for packaging are obtained from alginate, agar, starch, and glycerol as plasticizers. The tensile strength, elasticity, modulus of elasticity, thickness, density, microscopic images of the samples, roughness, opacity, humidity, water activity, the amount of water transferred as well as the speed of water transfer through these packaging materials were analyzed. A number of 28 samples with various compositions were analyzed, and the results showed that the sample with the highest values for hardness, density, and opacity, as well as the smallest water vapor permeability, of 1.2903E-4 ± 4.79E-6, has the ratio of components as alginate: agar: glycerol (3:1.25:0.75). The water activity of the analyzed films varied between 0.2886 and 0.3428 (aw< 0.6), demonstrating that all the compositions ensure the preservation of the products in the absence of microorganisms. All the determined parameters allow the appreciation of the quality of the packaging films in terms of mechanical resistance, its protection against the influence of light, the transfer of water through the packaging. Acknowledgments: This work was supported by a grant of the Ministry of Research, Innovation, and Digitization, CNCS/CCCDI – UEFISCDI, project number PN-III-P2-2.1-PED-2019-3863, within PNCDI III.

Keywords: meat products, alginate, agar, starch, glycerol

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Authors: Elmira Ghanbari, Jan Van Esch, Stephen J. Picken, Sahil Aggarwal

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Low-molecular-weight organogelators form gels by self-assembly into the crystalline network which immobilizes the organic solvent. For single bisamide organogelator systems, the effect of the molecular structure on the molecular interaction and their self-assembly behavior has been explored. The spatial arrangement of bisamide molecules in the gel-state is driven by a combination of hydrogen bonding and Van der Waals interactions. The hydrogen-bonding pattern between the amide groups of bisamide molecules is regulated by the number of methylene spacers; the even number of methylene spacers between two amide groups, in even-spaced bisamides, leads to the antiparallel position of amide groups within a molecule. An even-spaced bisamide molecule with antiparallel amide groups can make two pairs of hydrogen bonding with the molecules on the same plane. The odd-spaced bisamide with a parallel directionality of amide groups can form four independent hydrogen bonds with four other bisamide molecules on different planes. The arrangement of bisamide molecules in the crystalline state and the interaction of these molecules depends on the molecular structure, particularly the parity of the spacer length between the amide groups in the bisamide molecule. In this study, the directionality of amide groups has been exploited as a structural characteristic to affect the arrangement of molecules in the crystalline state and produce different binary bisamide gelators with different degrees of crystallinities. Single odd- and even-spaced single bisamides were synthesized and blended to produce binary bisamide organogelators to be characterized in order to understand the effect of the different directionality of amide groups on the molecular interaction in the crystalline state. The pattern of molecular interactions between these blended molecules, mixing or phase separation, has been monitored via differential scanning calorimetry (DSC) and crystallography techniques; X-ray powder diffraction (XRD) and Small-angle X-ray scattering (SAXS). The formation of lamellar structures for odd- and even-spaced bisamide gelators was confirmed by using SAXS and XRD techniques. DSC results have shown that binary bisamide organogelators with different parity of methylene spacers (odd-even binary blends) have a higher tendency for phase separation compared to the binary bisamides with the same parity (odd-odd or even-even binary blends). Phase separation in binary odd-even bisamides was confirmed by the presence of individual (100) reflections of odd and even lamellar structures. The structural characteristic of bisamide organogelators, the parity of spacer length in binary systems, is a promising tool to control the arrangement of molecules and their crystalline structure.

Keywords: binary bisamide organogelators, crystalline structure, phase separation, self-assembly behavior

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Authors: Sudeepti Dayal, Neelesh Gupta

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In terms of transmission, bigger the size of any image, longer the time the channel takes for transmission. It is understood that the bandwidth of the channel is fixed. Therefore, if the size of an image is reduced, a larger number of data or images can be transmitted over the channel. Compression is the technique used to reduce the size of an image. In terms of storage, compression reduces the file size which it occupies on the disk. Any image is based on two parameters, region of interest and non-region of interest. There are several algorithms of compression that compress the data more economically. In this paper we have reviewed region of interest and non-region of interest based compression techniques and the algorithms which compress the image most efficiently.

Keywords: compression ratio, region of interest, DCT, DWT

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Authors: T. Theodosiou, P. Polychronidou, A. G. Karasavvoglou

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The latest years the number of immigrants at Greece has increased dramatically. Their impact on the National Health System (NHS) has not been yet thoroughly investigated. This paper analyses the cost of immigrants to the NHS hospitals of the region of Eastern Macedonia and Thrace. The data are collected from 2005 to 2011 from five different hospitals and are analysed using linear mixed effects models in order to investigate the effects of nationality and year on the cost of hospitalization and treatment. The results show that generally the Greek nationality patients have a higher mean cost of hospitalization compared to the immigrants and that there is an increasing trend for the cost except for the year 2010.

Keywords: cost, Eastern Macedonia and Thrace, immigrants, national health system

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Authors: Ali Gul, Bhart Kumar, Samiullah Ansari

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The current research is focused on the study of various lengths of blades (i.e. 1 to 5m) and several bladed rotors (3,5,7 & 9) of small horizontal axis wind turbine under low wind conditions usingQBlade software. Initially, the rotor was designed using airfoil SG6043 with five different lengths of the blades. Subsequently, simulations were carried out in which, under low wind regimes, the power output was observed. Further, four rotors having 3,5,7 & 9 blades were analyzed. However, the most promising coefficient of performance (CP) was observed at the 3-bladed rotor. Both studies established a clear view of harvesting wind energy at low wind speeds that can be mobilized in the energy sector. That suggests the utilization of wind energy at the domestic levelwhich is acceleratory growing in the last few decades.

Keywords: small HAWT, QBlade, BEM, CFD

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Authors: Baya Takhedmit, Karim Abbas, Sofiane Ouazine

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The vacations queues are often employed to model many real situations such as computer systems, communication networks, manufacturing and production systems, transportation systems and so forth. These queueing models are solved at fixed parameters values. However, the parameter values themselves are determined from a finite number of observations and hence have uncertainty associated with them (epistemic uncertainty). In this paper, we consider the M/G/1/N queue with server vacation and exhaustive discipline where we assume that the vacation parameter values have uncertainty. We use the Taylor series expansions approach to estimate the expectation and variance of model output, due to epistemic uncertainties in the model input parameters.

Keywords: epistemic uncertainty, M/G/1/N queue with vacations, non-parametric sensitivity analysis, Taylor series expansion

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Authors: Jeanne-Mari Retief

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As of November 2016, three African states have withdrawn from the International Criminal Court (ICC) and more are expected to follow. The alleged abuse of universal jurisdiction and targeting of African states by the ICC motivated the withdrawals. These historical exits raise many questions, especially in regard to the adequate investigation and prosecution of international crimes in a continent with a history of impunity. Even though African courts exist and one more is proposed, many issues remain i.e. adequate access to the courts, the extent of the courts’ jurisdiction, and proposed methods of effectively dealing with international crimes in Africa. This paper seeks to address the practical effects of the withdrawal from the ICC and the problems posed through utilizing regional courts. It will specifically look at the practical challenges existing courts face, the lack of access to the latter, issues concerning the proposed African Court for Justice and Human Rights, and the shocking promotion of impunity in Africa. These all have severe implications for African citizens and victims of the most heinous crimes. The mantra of African solutions to African problems places an important duty on states to ensure the actual provision of these solutions, which can only be achieved through a critical analysis of the questions above.

Keywords: ACJHR, Africa, impunity, justice, Malabo protocol

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Authors: Zbigniew Czyz, Krzysztof Skiba, Miroslaw Wendeker

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This paper discusses the results of aerodynamic investigation of the Tajfun gyroplane body designed by a Polish company, Aviation Artur Trendak. This gyroplane has been studied as a 1:8 scale model. Scaling objects for aerodynamic investigation is an inherent procedure in any kind of designing. If scaling, the criteria of similarity need to be satisfied. The basic criteria of similarity are geometric, kinematic and dynamic. Despite the results of aerodynamic research are often reduced to aerodynamic coefficients, one should pay attention to how values of coefficients behave if certain criteria are to be satisfied. To satisfy the dynamic criterion, for example, the Reynolds number should be focused on. This is the correlation of inertial to viscous forces. With the multiplied flow speed by the specific dimension as a numerator (with a constant kinematic viscosity coefficient), flow speed in a wind tunnel research should be increased as many times as an object is decreased. The aerodynamic coefficients specified in this research depend on the real forces that act on an object, its specific dimension, medium speed and variations in its density. Rapid prototyping with a 3D printer was applied to create the research object. The research was performed with a T-1 low-speed wind tunnel (its diameter of the measurement volume is 1.5 m) and a six-element aerodynamic internal scales, WDP1, at the Institute of Aviation in Warsaw. This T-1 wind tunnel is low-speed continuous operation with open space measurement. The research covered a number of the selected speeds of undisturbed flow, i.e. V = 20, 30 and 40 m/s, corresponding to the Reynolds numbers (as referred to 1 m) Re = 1.31∙106, 1.96∙106, 2.62∙106 for the angles of attack ranging -15° ≤ α ≤ 20°. Our research resulted in basic aerodynamic characteristics and observing the impact of undisturbed flow speed on the correlation of aerodynamic coefficients as a function of the angle of attack of the gyroplane body. If the speed of undisturbed flow in the wind tunnel changes, the aerodynamic coefficients are significantly impacted. At speed from 20 m/s to 30 m/s, drag coefficient, Cx, changes by 2.4% up to 9.9%, whereas lift coefficient, Cz, changes by -25.5% up to 15.7% if the angle of attack of 0° excluded or by -25.5% up to 236.9% if the angle of attack of 0° included. Within the same speed range, the coefficient of a pitching moment, Cmy, changes by -21.1% up to 7.3% if the angles of attack -15° and -10° excluded or by -142.8% up to 618.4% if the angle of attack -15° and -10° included. These discrepancies in the coefficients of aerodynamic forces definitely need to consider while designing the aircraft. For example, if load of certain aircraft surfaces is calculated, additional correction factors definitely need to be applied. This study allows us to estimate the discrepancies in the aerodynamic forces while scaling the aircraft. This work has been financed by the Polish Ministry of Science and Higher Education.

Keywords: aerodynamics, criteria of similarity, gyroplane, research tunnel

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Authors: Paulo Sergio Altman Ferreira

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Relationship development plays an essential role in every logistics company. Logistics companies are service-based businesses essentially performing the flow of materials, housing, and inventory management for a wide range of customers. The service encounter between the logistics provider’s personnel and the customers may form a connection that will demonstrate a strong impact, not only to the customers' overall satisfaction but may also provide the perception of individualized services. Logistics services must drive value. It also shows a close influence on the quality and costs of client-centered services. If we describe logistics value creation as the function of quality perception of the client divided by service costs, there is a requirement to better outline and explain the measures and analytics for logistics costs and relationship performance. This critical shift to understand logistics services is a relevant contribution to capture how relationship value can be quantified. This might involve changing our current perspective on logistics providers beyond uniquely measuring the services in terms of activities, personnel levels, and financial/costs ratios. This paper argues that measuring value creation accomplishments of logistics services needs to consider the relational improvements for the wider range of logistics companies. Accurate logistics value requires a description of the financial impact of the relational perspective of the service.

Keywords: logistics services providers, financial metrics, relationship management, value creation

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Authors: Yoonjung An, Yongtae Park

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Knowledge flows are a critical source of faster technological progress and stouter economic growth. Knowledge flows have been accelerated dramatically with the establishment of a patent system in which each patent is required by law to disclose sufficient technical information for the invention to be recreated. Patent analysis, thus, has been widely used to help investigate technological knowledge flows. However, the existing research is limited in terms of both subject and approach. Particularly, in most of the previous studies, business method (BM) patents were not covered although they are important drivers of knowledge flows as other patents. In addition, these studies usually focus on the static analysis of knowledge flows. Some use approaches that incorporate the time dimension, yet they still fail to trace a true dynamic process of knowledge flows. Therefore, we investigate dynamic patterns of knowledge flows driven by BM patents using a Hidden Markov Model (HMM). An HMM is a popular statistical tool for modeling a wide range of time series data, with no general theoretical limit in regard to statistical pattern classification. Accordingly, it enables characterizing knowledge patterns that may differ by patent, sector, country and so on. We run the model in sets of backward citations and forward citations to compare the patterns of knowledge utilization and knowledge dissemination.

Keywords: business method patents, dynamic pattern, Hidden-Markov Model, knowledge flow

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Authors: Anil Khanal, Ali Osareh, Gary Lebby

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Wind energy offers a significant advantage such as no fuel costs and no emissions from generation. However, wind energy sources are variable and non-dispatchable. The utility grid is able to accommodate the variability of wind in smaller proportion along with the daily load. However, at high penetration levels, the variability can severely impact the utility reserve requirements and the cost associated with it. In this paper, the impact of wind energy is evaluated in detail in formulating the total utility cost. The objective is to minimize the overall cost of generation while ensuring the proper management of the load. Overall cost includes the curtailment cost, reserve cost and the reliability cost as well as any other penalty imposed by the regulatory authority. Different levels of wind penetrations are explored and the cost impacts are evaluated. As the penetration level increases significantly, the reliability becomes a critical question to be answered. Here, we increase the penetration from the wind yet keep the reliability factor within the acceptable limit provided by NERC. This paper uses an economic dispatch (ED) model to incorporate wind generation into the power grid. Power system costs are analyzed at various wind penetration levels using Linear Programming. The goal of this study shows how the increases in wind generation will affect power system economics.

Keywords: wind power generation, wind power penetration, cost analysis, economic dispatch (ED) model

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Authors: S. Ait Ali Yahia

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One of the main features of the Maghreb is its linguistic richness. The multilingualism is a fact which always marked the Maghreb since the beginning of the history up to know. Since the arrival of the Phoenicians, followed by the Carthaginians, Romans, and Arabs, etc, there was a social group in the Maghreb which controlled two kinds of idioms. The libyc one remained, despite everything, the local language used by the major part of the population. This language had a support of written transmission attested by many inscriptions. Among all the forms of the Maghreb writing, this alphabet, however, continues to cause a certain number of questions about the origin and the date of its appearance. The archaeological, linguistic and historical data remain insufficient to answer these questions. This did not prevent the researchers from giving an opinion. In order to answer these questions we will expose here the various assumptions adopted by various authors who are founded on more or less explicit arguments. We will also speak about the various forms taken by the libyc writing during antiquity.

Keywords: the alphabet libyc, Eastern libyc, Western libyc, multilingualism

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Authors: Jorine T. Ndoro, Marietjie Van Der Merwe

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Rural poverty remains a critical challenge in most developing countries and the participation of farmers in agricultural projects has taken a key role in development initiatives. Farmers’ participation in agricultural initiatives is crucial towards poverty alleviation and food security. Farmers’ involvement directly contributes towards sustainable agricultural development and livelihoods. This study focuses on investigating the perceptions of farmers’ participation in a community garden project. The study involved farmers belonging to community garden project in Imphendhle municipality in Mgungundlvu district of KwaZulu-Natal in South Africa. The study followed a qualitative research design using an interpretive research paradigm. The data was collected through conducting in-depth semi-structured interviews and a focus group was conducted with the eight farmers belonging to the community garden project. The findings show that the farmers are not involved in decision makings in the project. The farmers are passive participants. Participation of the farmers was mainly to carry out the activities from the extension officers. The study recommends that farmers be actively involved in projects and programmes introduced in their communities. Farmers’ active participation contributes to the sustainability of the projects through a sense of ownership.

Keywords: farmers, participation, agricultural extension, community garden

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Authors: Tsietsi J. Pilusa, Tumisang G. Seodigeng

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This study evaluates the benefits of advanced waste management practices in unlocking waste-to-energy opportunities within the solid waste industry. The key drivers of sustainable waste management practices, specifically with respect to packaging waste-to-energy technology options are discussed. The success of a waste-to-energy system depends significantly on the appropriateness of available technologies, including those that are well established as well as those that are less so. There are hard and soft interventions to be considered when packaging an integrated waste treatment solution. Technology compatibility with variation in feedstock (waste) quality and quantities remains a key factor. These factors influence the technology reliability in terms of production efficiencies and product consistency, which in turn, drives the supply and demand network. Waste treatment technologies rely on the waste material as feedstock; the feedstock varies in quality and quantities depending on several factors; hence, the technology fails, as a result. It is critical to design an advanced waste treatment technology in an integrated approach to minimize the possibility of technology failure due to unpredictable feedstock quality, quantities, conversion efficiencies, and inconsistent product yield or quality. An integrated waste-to-energy approach offers a secure system design that considers sustainable waste management practices.

Keywords: emerging markets, evaluation tool, interventions, waste treatment technologies

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Authors: Fatemeh Abdollahi, Munn-Sann Lye, Jamshid Yazdani Charati, Mehran Zarghami

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Background: In March 2020, the World Health Organization (WHO) declared the outbreak of a new coronavirus disease, COVID-19, as a public health concern and pandemic. This situation is generating psychological consequences such as stress, anxiety, depression, and intimate partner violence (IPV) throughout the population. This is a brief note on the magnitude of this threat and different ways for abused women to minimize the effects of it in their daily life. Methods: A literature review was conducted using the MEDLINE, PSYCHINFO, and SCIENCE DIRECT databases. The keywords used included intimate partner violence, abuse, victims, pandemic, quarantine, coronavirus, and COVID-19. A Google search was also conducted using these words to identify reports published in non-indexed health care and social science journals. The literature search was restricted to English language studies. Results: The prevalence of IPV and its consequences are rising during such a pandemic. Having sufficient support from healthcare workers and acquaintances is critical for women in such circumstances. Conclusion: Community members, healthcare providers, governments, and policymakers should be informed of the increased risk of IPV during such a pandemic. They should provide a supporting structure for abused women. Social networking is also a good approach that could help abusive women during this situation.

Keywords: covid-19, intimate partner violence, pandemic, women

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Authors: Seyedmajid Mehrnia, Maximilan Kuhr, Peter F. Pelz

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Molecular Dynamics (MD) simulation is a proven method to inspect behaviours of lubricant oils in nano-scale gaps. However, most MD simulations on tribology have been performed with atomically smooth walls to determine wall slip and friction properties. This study will investigate the effect of porosity, specifically nano-porous walls, on wall slip properties of hydrocarbon oils confined between two walls in a Couette flow. Different pore geometries will be modelled to investigate the effect on wall slip and bulk shear. In this paper, the Polyalphaolefin (PAO) molecules are confined to a stationary and a moving wall. A hybrid force field consisting of different potential energy functions was employed in this MD simulation. Newton’s law defines how those forces will influence the atoms' movements. The interactions among surface atoms were simulated with an Embedded Atom Method (EAM) potential function which can represent the characteristics of metallic arrangements very strongly. We implemented NERD forcefield for intramolecular potential energy function. Also, Lennard-Jones potential was employed for nonbonded intermolecular interaction.

Keywords: slip length, molecular dynamics, critical shear rate, Couette flow

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Authors: Ana Teixeira, Joao Orvalho

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This paper describes experiments using Scratch games, to check the feasibility of employing cerebral palsy users gestures as an alternative of interaction with a computer carried out by students of Master Human Computer Interaction (HCI) of IPC Coimbra. The main focus of this work is to study the usability of a Web Camera as a motion tracking device to achieve a virtual human-computer interaction used by individuals with CP. An approach for Human-computer Interaction (HCI) is present, where individuals with cerebral palsy react and interact with a scratch game through the use of a webcam as an external interaction device. Motion tracking interaction is an emerging technology that is becoming more useful, effective and affordable. However, it raises new questions from the HCI viewpoint, for example, which environments are most suitable for interaction by users with disabilities. In our case, we put emphasis on the accessibility and usability aspects of such interaction devices to meet the special needs of people with disabilities, and specifically people with CP. Despite the fact that our work has just started, preliminary results show that, in general, computer vision interaction systems are very useful; in some cases, these systems are the only way by which some people can interact with a computer. The purpose of the experiments was to verify two hypothesis: 1) people with cerebral palsy can interact with a computer using their natural gestures, 2) scratch games can be a research tool in experiments with disabled young people. A game in Scratch with three levels is created to be played through the use of a webcam. This device permits the detection of certain key points of the user’s body, which allows to assume the head, arms and specially the hands as the most important aspects of recognition. Tests with 5 individuals of different age and gender were made throughout 3 days through periods of 30 minutes with each participant. For a more extensive and reliable statistical analysis, the number of both participants and repetitions in further investigations should be increased. However, already at this stage of research, it is possible to draw some conclusions. First, and the most important, is that simple scratch games on the computer can be a research tool that allows investigating the interaction with computer performed by young persons with CP using intentional gestures. Measurements performed with the assistance of games are attractive for young disabled users. The second important conclusion is that they are able to play scratch games using their gestures. Therefore, the proposed interaction method is promising for them as a human-computer interface. In the future, we plan to include the development of multimodal interfaces that combine various computer vision devices with other input devices improvements in the existing systems to accommodate more the special needs of individuals, in addition, to perform experiments on a larger number of participants.

Keywords: motion tracking, cerebral palsy, rehabilitation, HCI

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Authors: A. G. Gashua, T. T. Bello, I. Alhassan, K. K. Gwiokura

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Weeds are known to interfere seriously with crop growth, thereby affecting the productivity and quality of crops. Crops are also known to compete for natural growth resources if they are not adequately spaced, also affecting the performance of the growing crop. Farmers grow cowpea in mixtures with cereals and this is known to affect its yield. For this reason, a field experiment was conducted at Yobe State College of Agriculture Gujba, Damaturu station in the 2014 and 2015 rainy seasons to determine the appropriate intra row spacing and weeding regime for optimum growth and yield of cowpea (Vigna unguiculata L.) in pure stand in Sudan Savanna ecology. The treatments consist of three levels of spacing within rows (20 cm, 30 cm and 40 cm) and four weeding regimes (none, once at 3 weeks after sowing (WAS), twice at 3 and 6WAS, thrice at 3WAS, 6WAS and 9WAS); arranged in a Randomized Complete Block Design (RCBD) and replicated three times. The variety used was the local cowpea variety (white, early and spreading) commonly grown by farmers. The growth and yield data were collected and subjected to analysis of variance using SAS software, and the significant means were ranked by Students Newman Keul’s test (SNK). The findings of this study revealed better crop performance in 2015 than in 2014 despite poor soil condition. Intra row spacing significantly influenced vegetative growth especially the number of main branches, leaves and canopy spread at 6WAS and 9WAS with the highest values obtained at wider spacing (40 cm). The values obtained in 2015 doubled those obtained in 2014 in most cases. Spacing also significantly affected the number of pods in 2015, seed weight in both years and grain yield in 2014 with the highest values obtained when the crop was spaced at 30-40 cm. Similarly, weeding regime significantly influenced almost all the growth attributes of cowpea with higher values obtained from where cowpea was weeded three times at 3-week intervals, though statistically similar results were obtained even from where cowpea was weeded twice. Weeding also affected the entire yield and yield components in 2015 with the highest values obtained with increase weeding. Based on these findings, it is recommended that spreading cowpea varieties should be grown at 40 cm (or wider spacing) within rows and be weeded twice at three-week intervals for better crop performance in related ecologies.

Keywords: intra-row spacing, local cowpea, Nigeria, weeding

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Authors: Zhidong Zhang, Zhi-Chao Zhang, Georgianna Duarte

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This study investigated the attention problems with the instrument of Achenbach System of Empirically Based Assessment (ASEBA). Two thousand eight hundred and ninety-four adolescents were surveyed by using a stratified sampling method. We examined the relationships between relevant background variables and attention problems. Multiple regression models were applied to analyze the data. Relevant variables such as sports activities, hobbies, age, grade and the number of close friends were included in this study as predictive variables. The analysis results indicated that educational environments and extracurricular activities are important factors which influence students’ attention problems.

Keywords: adolescents, ASEBA, attention problems, educational environments, stratified sampling

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Authors: Josip Arneric, Antonio Sostaric

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Crikvenica is one of the favourite tourist destinations at the Adriatic Sea in Croatia which attracts guests with its natural beauties and is one of the top destinations with the highest number of overnights stays. The main purpose of this research is to determine which elements of tourist offer should be improved to achieve sustainable development of the town of Crikvenica. Namely, the survey results from a random sample have shown that the most common reason of the visits is relaxation and vacation, and that more attention should be given to the following categories: restaurants and the working hours of stores and banks. We have also examined whether or not there is a correlation between an average daily expenditure and the overnight stay. The paper ends with the conclusion and the recommendations on how to improve the tourist offer of Crikvenica in order to increase guest satisfaction and to keep its reputation at a high level.

Keywords: tourism development, survey, Crikvenica, management sciences

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Authors: Neeti Rustagi, Naveen Dutt, Arvind Sinha, Mahaveer S. Rhodha, Pankaja R. Raghav

Abstract:

Background: Pre-hospital trauma care services are in developing stage in fast-urbanizing cities of India including Jodhpur. Training of health professionals in providing necessary pre-hospital trauma care is an essential step in decreasing accident related morbidity and mortality. The current study explores the response of a medical graduate toward helping an accident victim in a pre-hospital setting before patient can be transferred to definitive trauma facility. Methodology: This study examines the perceived competence in predicting response to an accident victim by medical graduates in Jodhpur, Rajasthan. Participants completed measures of attitude, normative influence and perceived behavior control toward providing pre-hospital care to an accident victim. Likert scale was used to measure the participant responses. Preliminary and descriptive analysis were used using SPSS 21.0. Internal consistency of the responses received was measured using Cronbach’s alpha. Results: Almost all medical graduates agreed that road accidents are common in their area (male: 92%; female: 78%). More male medical graduates (28%) reported helping an accident victim as compared to female physicians (9%) in the previous three months. Majority of study participants (96%) reported that providing immediate care to an accident victim is essential to save the life of an individual. Experience of helping an accident victim was considered unpleasant by the majority of female participants (70%) as compared to male participants (36%). A large number of participants believed that their friends (80%) and colleagues (96%) would appreciate them helping an accident victim in a pre-hospital setting. A large number of participants also believed that they possess the necessary skills and competencies (80%) towards helping a roadside accident victim in the pre-hospital care environment. Perceived competence of helping a roadside accident victim until they are transferred to a health facility was reported by less than half of the participants (male: 56%; female: 43%). Conclusion: Medical graduates have necessary attitude, competencies, and intention of helping a roadside accident victim. The societal response towards helping a road side accident victim is also supportive. In spite of positive determinants, a large proportion of medical graduates have perceived lack of competence in helping a roadside accident victim. This is essential to explore further as providing pre-hospital care to a roadside accident victim is an essential step in establishing the continuum of care to an accident victim especially in countries where pre-hospital services are in developing phase.

Keywords: prehospital care, perceived behavior, perceived competence, medical graduates

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Authors: Zorica Tomičić, Ružica Tomičić, Peter Raspor

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Growing resistance of pathogenic yeast Candida glabrata to many classes of antifungal drugs has stimulated efforts to discover new agents to combat a rising number of invasive C. glabrata infections, which deserves a great deal of concern due to the high mortality rate in immunocompromised populations. One promising strategy is the use of probiotic microorganisms, which, when administered in adequate amounts, confers a health benefit. A selected number of probiotic organisms, Saccharomyces boulardii among them, have been tested as potential biotherapeutic agents. The aim of this study was to investigate the effect of the probiotic yeast S. boulardii on the adhesion of clinical isolates of C. glabrata at different temperatures, pH values, and in the presence of three clinically important antifungal drugs, such as fluconazole, itraconazole and amphotericin B. The method used to assess adhesion was crystal violet staining. The selection of antimycotics concentrations used in the adhesion assay was based on minimum inhibitory concentrations (MICs) obtained by the preliminarily performed microdilution modification of the Reference method for broth dilution antifungal susceptibility testing of yeast (Clinical and Laboratory Standards Institute (CLSI), standard M27-A2). the results showed that despite the nonadhesiveness of S. boulardii cells, probiotic yeast significantly suppressed the adhesion of C. glabrata strains. Besides, at specific strain ratios, a slight stimulatory effect was observed in some C. glabrata strains, which highlights the importance of strain specificity and opens up further research interests. When environmental conditions are considered, temperature and pH significantly influenced co-culture adhesion of C. glabrata and S. boulardii. The adhesion of C. glabrata strains was relatively equally reduced over all tested temperature range (28°C, 37°C, 39°C and 42°C) in the presence of S. boulardii cells, while the adhesion of a few C. glabrata strains were significantly stimulated at 28°C and suppressed at 42°C. Further, the adhesion was highly dependent on pH, with the highest adherence at pH 4 and lowest at pH 8.5. It was observed that S. boulardii did not manage to suppress the adhesion of C. glabrata strains at high pH. Antimycotics on the other hand showed a greater impact, since S. boulardii failed to affect co-culture adhesion at higher antimycotics concentrations. As expected, exposure to various concentrations of amphotericin B significantly reduced the adherence ability of C.glabrata strains both in a single culture and co-culture with S. boulardii. Therefore, it can be speculated that S. boulardii could substitute the effect of antimycotics in a range concentrations and with specific type of strains. This would certainly change the view on the treatment of yeast infections in the future.

Keywords: adhesion, antimycotics, candida glabrata, saccharomyces boulardii

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Authors: Rendani Mercy Makhwathana

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This paper intends to explore the experiences and views of Foundation Phase teachers when teaching English First Additional Language in rural public schools. Teachers all over the world are pillars of any education system. Consequently, any education transformation should start with teachers as critical role players in the education system. As a result, teachers’ experiences and views are worth consideration, for they impact on learners learning and the wellbeing of education in general. An exploratory qualitative approach with the use of phenomenological research design was used in this paper. The population for this paper comprised all Foundation Phase teachers in the district. Purposive sampling technique was used to select a sample of 15 Foundation Phase teachers from five rural-based schools. Data was collected through classroom observation and individual face-to-face interviews. Data were categorised, analysed and interpreted. The findings revealed that from time-to-time teachers experiences one or more challenging situations, learners’ low participation in the classroom to lack of resources. This paper recommends that teachers should be provided with relevant resources and support to effectively teach English First Additional Language.

Keywords: the education system, first additional language, foundation phase, intermediate phase, language of learning and teaching, medium of instruction, teacher professional development

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Authors: Pietro Mortini, Marco Losa

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Objective: Resection of large lesions growing into the third ventricle remains a demanding surgery, sometimes at risk of severe post-operative complications. Transcallosal and transcortical routes were considered as approaches of choice to access the third ventricle, however neurological consequences like memory loss have been reported. We report clinical results of the previously described combined interhemispheric sub-commissural translaminaterminalis approach (CISTA) for the resection of large lesions located in the third ventricle. Methods: Authors conducted a retrospective analysis on 10 patients, who were operated through the CISTA, for the resection of lesions growing into the third ventricle. Results: Total resection was achieved in all cases. Cognitive worsening occurred only in one case. No perioperative deaths were recorded and, at last follow-up, all patients were alive. One year after surgery 80% of patients had an excellent outcome with a KPS 100 and Glasgow Outcome score (GOS) Conclusion: The CISTA represents a safe and effective alternative to transcallosal and transcortical routes to resect lesions growing into the third ventricle. It allows for a multiangle trajectory to access the third ventricle with a wide working area free from critical neurovascular structures, without any section of the corpus callosum, the anterior commissure and the fornix.

Keywords: craniopharingioma, surgery, sub-commissural translaminaterminalis approach (CISTA),

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Authors: Peter Dzakah Fanam, Hong O. Nguyen, Stephen Cahoon

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The objective of this study is to explore the buying behavior of the freight forwarders and to evaluate how their buying decision affects the ocean container carriers’ market share. This study analysed the buying decisions of the freight forwarders and validated the process of stages that the freight forwarders’ pass through before choosing an ocean container carrier. Factor analysis was applied to data collected from 105 freight forwarding companies to unveil the influential factors the freight forwarders’ consider important when selecting an ocean container carrier. This study did not only analysed the buying behaviour of the freight forwarders but also unveiled the influential factors affecting the competitiveness of the ocean container carriers in their market share maximisation. Furthermore, the study have made a methodological contribution that helps in better understanding of the critical factors influencing the selection of the ocean container carriers from the freight forwarders’ perspective. The implications of the freight forwarders’ buying behaviour is important to the ocean container carriers because it have severe effect on the market share of the ocean container carriers and the percentage of customers they control within the liner shipping sector. The findings of this study will help the ocean container carriers to formulate relevant marketing strategies in attracting the freight forwarders in purchasing the liner shipping service.

Keywords: ocean carrier, freight forwarder, buying behaviour, influential factors

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Authors: S. Nagheli, N. Samani, D. A. Barry

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In this paper, the velocity potential and stream function of capture zone for a well field in an aquifer bounded by two parallel streams with or without a uniform regional flow of any directions are presented. The well field includes any number of extraction or injection wells or a combination of both types with any pumping rates. To delineate the capture envelope, the potential and streamlines equations are derived by conformal mapping method. This method can help us to release constrains of other methods. The equations can be applied as useful tools to design in-situ groundwater remediation systems, to evaluate the surface–subsurface water interaction and to manage the water resources.

Keywords: complex potential, conformal mapping, image well theory, Laplace’s equation, superposition principle

Procedia PDF Downloads 427