Search results for: maximum entropy principle

Authors: S. Louhibi-Fasla, H. Rekab Djabri, H. Achour

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The aim of this work is to investigate the structural phase-transitions and electronic properties of copper halides. Our calculations were performed within the PLW extension to the first principle FPLMTO method, which enables an accurate treatment of all kinds of structures including the open ones. Results are given for lattice parameters, bulk modulus and its first derivatives in five different surface phases, and are compared with the available theoretical and experimental data. In the zinc-blende (B3) and PbO (B10) phases, the fundamental gap remains direct with both the top of VB and the bottom of CB located at Γ.

Keywords: FPLMTO, structural properties, Copper halides, phase transitions, ground state phase

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Authors: Divine Kwaku Ahadzie

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Project management (PM) as a concept has evolved from the early 20th Century into a recognized academic and professional discipline, and indications are that it has come to stay in the 21st Century as a world-wide paradigm shift for managing successful construction projects. However, notwithstanding the strong inroads that PM has made in legitimizing its academic and professional status in construction management practice, the underlining philosophies are still based on cases and conventional practices. An important theoretical issue yet to be addressed is the lack of a universal theory that offers philosophical legitimacy for the PM concept as a uniquely specialized management concept. Here, it is hypothesized that the law of entropy, the theory of uncertainties and the theory of risk management offer plausible explanations for addressing the lacuna of what constitute PM theory. The theoretical bases of these plausible underlying theories are argued and attempts made to establish the functional relationships that exist between these theories and the PM concept. The paper then draws on data related to the success and/or failure of a number of construction projects to validate the theory.

Keywords: concepts, construction, project management, universal theory

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Authors: Masahiro Suzuki, Nobuyuki Okura

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The crosswind effect on ground transportations has been extensively investigated for decades. The effect of tornado, however, has been hardly studied in spite of the fact that even heavy ground vehicles, namely, trains were overturned by tornadoes with casualties in the past. Therefore, aerodynamic effects of the tornado on the train were studied by several approaches in this study. First, an experimental facility was developed to clarify aerodynamic forces acting on a vehicle running through a tornado. Our experimental set-up consists of two apparatus. One is a tornado simulator, and the other is a moving model rig. PIV measurements showed that the tornado simulator can generate a swirling-flow field similar to those of the natural tornadoes. The flow field has the maximum tangential velocity of 7.4 m/s and the vortex core radius of 96 mm. The moving model rig makes a 1/40 scale model train of single-car/three-car unit run thorough the swirling flow with the maximum speed of 4.3 m/s. The model car has 72 pressure ports on its surface to estimate the aerodynamic forces. The experimental results show that the aerodynamic forces vary its magnitude and direction depends on the location of the vehicle in the flow field. Second, the aerodynamic forces on the train were estimated by using Rankin vortex model. The Rankin vortex model is a simple tornado model which widely used in the field of civil engineering. The estimated aerodynamic forces on the middle car were fairly good agreement with the experimental results. Effects of the vortex core radius and the path of the train on the aerodynamic forces were investigated using the Rankin vortex model. The results shows that the side and lift forces increases as the vortex core radius increases, while the yawing moment is maximum when the core radius is 0.3875 times of the car length. Third, a computational simulation was conducted to clarify the flow field around the train. The simulated results qualitatively agreed with the experimental ones.

Keywords: aerodynamic force, experimental method, tornado, train

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Authors: Shatirah Akib, Hossein Basser, Hojat Karami, Afshin Jahangirzadeh

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Bridge piers which are constructed in the track of high water rivers cause some variations in the flow patterns. This variation mostly is a result of the changes in river sections. Decreasing the river section, bridge piers significantly impress the flow patterns. Once the flow approaches the piers, the stream lines change their order, causing the appearance of different flow patterns around the bridge piers. New flow patterns are created following the geometry and the other technical characteristics of the piers. One of the most significant consequences of this event is the scour generated around the bridge piers which threatens the safety of the structure. In order to determine the properties of scour holes, to find maximum depth of the scour is an important factor. In this manuscript a numerical simulation of the scour around Marand-Soofian route bridge piers has been carried out via SSIIM 2.0 Software and the amount of maximum scour has been achieved subsequently. Eventually the methods for retrofitting of bridge piers against scours and also the methods for decreasing the amount of scour have been offered.

Keywords: scour, bridge pier, numerical simulation, SSIIM 2.0

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Authors: Deliou Adel, Saadalah Younes, Belkaid Khmissi, Dehbi Meriem

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Composite materials, in the most common sense of the term, are a set of synthetic materials designed and used mainly for structural applications; the mechanical function is dominant. The mechanical behaviors of the composite, as well as the degradation mechanisms leading to its rupture, depend on the nature of the constituents and on the architecture of the fiber preform. The profile is required because it guides the engineer in designing structures with precise properties in relation to the needs. This work is about studying the mechanical behavior of unidirectional composite laminates according to different failure criteria. Varying strength parameter values make it possible to compare the ultimate mechanical characteristics obtained by the criteria of Tsai-Hill, Fisher and maximum stress. The laminate is subjected to uniaxial tensile membrane forces. Estimates of their ultimate strengths and the plotting of the failure envelope constitute the principal axis of this study. Using the theory of maximum stress, we can determine the various modes of damage of the composite. The different components of the deformation are presented for different orientations of fibers.

Keywords: unidirectional kevlar/epoxy composite, failure criterion, membrane stress, deformations, failure envelope

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Authors: Konstancja Syller

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International law and European regulations remain hardly silent about the admissibility of evidence obtained illegally in a criminal trial. However, Article 6 of the European Convention on Human Rights guarantees the right to a fair trial, it does not normalise a proceeding status of specified sources or means of proof outright. Therefore, it is the preserve of national legislation and national law enforcement authorities to decide on this matter. In most countries, especially in Germany and Poland, a rather complex normative approach to the issue of proof obtained in violation of the right to privacy is evident, which pursues in practise to many interpretive doubts. In Germany the jurisprudence has a significant impact within the range of the matter mentioned above. The Constitutional Court and the Supreme Court of Germany protect the right to privacy quite firmly - they ruled on inadmissibility of obtaining a proof in the form of a diary or a journal as a protection measure of constitutional guaranteed right. At the same time, however, the Supreme Court is not very convinced with reference to the issue of whether materials collected as a result of an inspection, call recordings or listening to the premises, which were carried out in breach of law, can be used in a criminal trial. Generally speaking, German courts indicate a crucial importance of the principle of Truth and the principle of proportionality, which both enable a judgement to be made as to the possibility of using an evidence obtained unlawfully. Comparing, in Poland there is almost no jurisprudence of the Constitutional Tribunal relating directly to the issue of illegal evidence. It is somehow surprising, considering the doctrinal analysis of the admissibility of using such proof in a criminal trial is performed in relation to standards resulted from the Constitution. Moreover, a crucial de lega lata legal provision, which enables allowing a proof obtained in infringement of the provisions in respect of criminal proceedings or through a forbidden act, is widely criticised within the legal profession ant therefore many courts give it their own interpretation at odds with legislator’s intentions. The comparison of two civil law legal systems’ standards regarding to the admissibility of an evidence obtained in contravention of the right to privacy in a criminal trial, taking also into account EU legislation and judicature, is the conclusive aim of this article.

Keywords: criminal trial, evidence, Germany, right to privacy, Poland

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Authors: Hamza I. Isa, Gezina C. H. Ferreira, Jan E. Crafford, Christoffel J. Botha

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Moraea pallida Bak. (yellow tulip) poisoning is the most important plant-induced cardiac glycoside toxicosis in South Africa. Cardiac glycoside poisonings collectively account for about 33 and 10 % mortalities due to plants, in large and small stock respectively, in South Africa. The toxic principle is 1α, 2α-epoxyscillirosidine, a bufadienolide. The aim of the study was to investigate the potential to develop a vaccine against epoxyscillirosidine. Epoxyscillirosidine and the related bufadienolides proscillaridin and bufalin, which are commercially available, were conjugated to the carrier proteins [Hen ovalbumin (OVA), bovine serum albumin (BSA) and keyhole limpet haemocyanin (KLH)], rendering them immunogenic. Adult male New Zealand White rabbits were immunized. In Trials 1 and 2, rabbits (n=6) were, each assigned to two groups. Experimental animals (n=3; n=4) were vaccinated with epoxyscillirosidine-OVA conjugate, while the control (n=3; n=2) were vaccinated with OVA, using Freund’s complete and incomplete and Montanide adjuvants, for Trials 1 and 2, respectively. In Trial 3, rabbits (n=15), randomly allocated to 5 equal groups (I, II, III, IV and V), were vaccinated with proscillaridin-BSA, bufalin-BSA, epoxyscillirosidine-KLH, epoxyscillirosidine-BSA conjugates, and BSA respectively, using Montanide as adjuvant. Vaccination was on Days 0, 21 and 42. Additional vaccinations were done on Day 56 and 63 for Trial 1. Vaccination was by intradermal injection of 0.4 ml of the immunogen (4 mg/ml [Trial 1] and 8 mg/ml for Trials 2 and Trial 3, respectively). Blood was collected pre-vaccination and at 3 week intervals following each vaccination. Antibody response was determined using an indirect ELISA. There was poor immune response associated with the dose (0.4 mg per rabbit) and adjuvant used in Trial 1. Antibodies were synthesized against the conjugate administered in Trial 2. For Trail 3, antibodies against the immunogens were successfully raised in rabbits with epoxyscillirosidine-KLH inducing the highest immune response. The antibodies raised against proscillaridin and bufalin cross-reacted with epoxyscillirosidine when used as antigen in the ELISA. The study successfully demonstrated the synthesis of antibodies against the bufadienolide conjugates administered. The cross-reactivity of proscillaridin and bufalin with epoxyscillirosidine could potentially be utilized as alternative to epoxyscillirosidine in future studies to prevent yellow tulp poisoning by vaccination.

Keywords: antibodies , bufadienolides, cross-reactivity, epoxyscillirosidine, Moraea pallida, poisoning

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Authors: Farhad Hekmatipour, M. A. Akhavan-Behabadi, Farzad Hekmatipour

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In this paper, experiments were conducted to investigate the heat transfer of Copper Oxide-Heat Transfer Oil (CuO-HTO) nanofluid laminar flow in vertical smooth and microfin tubes as the surface temperature is constant. The effect of adding the nanoparticle to base fluid and Richardson number on the heat transfer enhancement is investigated as Richardson number increases from 0.1 to 0.7. The experimental results demonstrate that the combined forced-natural convection heat transfer rate may be improved significantly with an increment of mass nanoparticle concentration from 0% to 1.5%. In this experiment, a correlation is also proposed to predict the mixed convection heat transfer rate of CuO-HTO nanofluid flow. The maximum deviation of both correlations is less than 14%. Moreover, a correlation is presented to estimate the Nusselt number inside vertical smooth and microfin tubes as Rayleigh number is between 2´105 and 6.8´106 with the maximum deviation of 12%.

Keywords: mixed convection, heat transfer, nanofluid, vertical tube, microfin tube

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Authors: A. Zaher, A. Traore, F. Thiéry, T. Talbert, B. Shaer

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In this paper, an intelligent approach is proposed to optimize the orientation of continuous solar tracking systems on cloudy days. Considering the weather case, the direct sunlight is more important than the diffuse radiation in case of clear sky. Thus, the panel is always pointed towards the sun. In case of an overcast sky, the solar beam is close to zero, and the panel is placed horizontally to receive the maximum of diffuse radiation. Under partly covered conditions, the panel must be pointed towards the source that emits the maximum of solar energy and it may be anywhere in the sky dome. Thus, the idea of our approach is to analyze the images, captured by ground-based sky camera system, in order to detect the zone in the sky dome which is considered as the optimal source of energy under cloudy conditions. The proposed approach is implemented using experimental setup developed at PROMES-CNRS laboratory in Perpignan city (France). Under overcast conditions, the results were very satisfactory, and the intelligent approach has provided efficiency gains of up to 9% relative to conventional continuous sun tracking systems.

Keywords: clouds detection, fuzzy inference systems, images processing, sun trackers

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Authors: Islam Zeb

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The water of poor quality used for irrigation purposes has the potential to be the direct source of contamination and a vehicle for spreading contamination in the field. A number of wide-ranging review articles have been published that highlight irrigation water as a source of heavy metals toxicity which leads to chronic diseases in the human body. Here a study was planned to determine the microbial and heavy metals status of irrigation water collected from various locations of district Swat in various months. The analyses were carried out at the Environmental Horticulture Laboratory, Department of Horticulture, The University of Agriculture Peshawar, during the year 2018 – 19. The experiment was laid out in Randomized Complete Block Design (RCBD) with two factors and three replicates. Factor A consist of different locations and factor B represent various months. The result of heavy metals concentration in different regions, maximum Lead, Cadmium, Chromium, Nickel and Copper (4.27, 0.56, 0.81, 1.33 and 1.51 mg L-1 respectively) were noted for the irrigation water samples collected from Mingora while minimum Lead, Cadmium, Chromium, Nickel and Copper concentration (2.59, 0.30, 0.27, 0.40 and 0.54 mg L-1 respectively) were noted for the samples of matta. Whereas results of heavy metals content in irrigation water samples for various months maximum content of Lead, Cadmium, Chromium, Nickel and Copper (4.56, 0.63, 1.15, 1.31 and 1.48 mg L-1 respectively) were noted for the samples collected in Jan/Feb while lowest values for Lead, Cadmium, Chromium, Nickel and Copper (2.38, 0.24, 0.21, 0.41 and 0.52 mg L-1 respectively) were noted in the samples of July/August. A significant interaction was found for all the studied parameters. It was concluded that the concentration of heavy metal was maximum in irrigation water samples collected from the Mingora location during the month of Jan/Feb because Mingora is the most polluted area as compared to other studied regions, whereas the water content in winter goes to freeze and mostly contaminated water is used for irrigation purposes.

Keywords: irrigation water, various months, different regions, heavy metals contamination, Swat

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Authors: C. Han, H. Kim, S. Park

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The purpose of the present study is to analyze the effect of surface roughness on fatigue life of SCM440 steel. Two groups of specimens were made from SCM440 steel with and without surface polished after forging process and resulted in different values of surface roughness. The difference of the surface roughness between two groups was clearly distinguished even to the naked eye. Surface roughness of both groups of the specimens was quantitatively measured by a roughness measuring device, Talysurf series2 (Taylor-Hobson Co., USA). Average roughness (Ra) and maximum roughness depth (Rmax) values were obtained by scanning 45 mm with a speed of 0.25 mm/s. Fatigue tests were conducted using a three-point bending method with a cyclic sinusoidal profile of 5 Hz, stress ratio of R = 0.1 and reference life for fatigue limit of 1 × 106 cycles. Ra and Rmax without surface polished were 10.497 ± 1.721 μm and 87.936 ± 16.210 μm, respectively while those values with surface polished were much smaller (ongoing measurements). Fatigue lives of the surface-polished specimens achieved approximately 1 × 106 cycles under the maximum stress of 900 MPa, which was 10 times longer than those of the surface-untreated specimens with an average roughness of 10.082 μm. The results showed that an increase in surface roughness values led to a decrease in fatigue lives.

Keywords: surface roughness, fatigue test, fatigue life, SCM440 steel

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Authors: Lakhminandan Kakati, Merenjungla Jamir

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Rearing of six strains of Samia ricini (eri silk worm) i.e. Yellow plain (YP), Yellow spotted (YS), Yellow Zebra (YZ), Greenish blue plain (GBP), Greenish blue spotted (GBS) and Greenish blue zebra (GBZ) was conducted on Ricinus communis (Castor), Heteropanax fragrans (Kesseru), Evodia fraxinifolia (Payam) and Manihot utilissima (Tapioca) to evaluate the effect of seasonal pattern on larval duration and cocoon parameters in Nagaland, India. Larval duration during spring season was maximum in all strains in all food plants; however minimum for all strains was recorded during summer season on Castor, Kesseru and Tapioca. Cocoon weight was recorded to be minimum (2.8 ± 2 0.55 gm) in YP on Kesseru and maximum (4.06 ± 0.68 gm) in GBZ on Castor during spring season; shell weight fluctuated between 0.34 ± 0.08 gm during spring in GBS on Kesseru and 0.58 ± 0.09 gm during summer in YZ on Castor and percentage of silk ratio was found to be minimum and maximum in YP on Payam during spring (11.37 ± 1.29) and in GBS on Castor during summer (16.05 ± 1.59) respectively. The variation in larval duration and cocoon parameters reflected variation in nutrient composition of food plants and dynamic environment conditions prevailing in different seasons of the year. Payam and Tapioca plants could be fed either singly or alternately with Castor or Kesseru to attain the commercial advantage to ensure more value added production. While there were differences in the productivity parameters with respect to strains and seasons, the present study shows that all the strains on four host plants expressed adaptability and suitability for commercial rearing under Nagaland climatic condition.

Keywords: alternative food plants, Larval and cocoon parameters, Nagaland Inia, six strains of Samia ricini

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Authors: Woei-Shyan Lee, Shuo-Ling Chang

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The nanoindentation behaviour and phase transformation of annealed single-crystal silicon wafers are examined. The silicon specimens are annealed at temperatures of 250, 350 and 450ºC, respectively, for 15 minutes and are then indented to maximum loads of 30, 50 and 70 mN. The phase changes induced in the indented specimens are observed using transmission electron microscopy (TEM) and micro-Raman scattering spectroscopy (RSS). For all annealing temperatures, an elbow feature is observed in the unloading curve following indentation to a maximum load of 30 mN. Under higher loads of 50 mN and 70 mN, respectively, the elbow feature is replaced by a pop-out event. The elbow feature reveals a complete amorphous phase transformation within the indented zone, whereas the pop-out event indicates the formation of Si XII and Si III phases. The experimental results show that the formation of these crystalline silicon phases increases with an increasing annealing temperature and indentation load. The hardness and Young’s modulus both decrease as the annealing temperature and indentation load are increased.

Keywords: nanoindentation, silicon, phase transformation, amorphous, annealing

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Authors: M. Ibrir, S. Berri, S. Lakel, D. Maouche And Y. Medkour

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We have performed first-principle calculations of the structural, electronic and magnetic properties of KFeF3, KCoF3, KMnF3, KVF3, using full-potential linearized augmented plane-wave (FP-LAPW) scheme within GGA. Features such as the lattice constant, bulk modulus and its pressure derivative are reported. Also, we have presented our results of the band structure and the density of states. The magnetic moments of KFeF3, KCoF3, KMnF3, KVF3 compounds are in most came from the exchange-splitting of X-3d orbital.

Keywords: Ab initio calculations, electronic structure, magnetic materials

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Authors: Essa Abrahim Abdulgader Saleem, Thien-My Dao

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The main objective of this paper is to optimize series-parallel system reliability using Genetic Algorithm (GA) and statistical analysis; considering system reliability constraints which involve the redundant numbers of selected components, total cost, and total weight. To perform this work, firstly the mathematical model which maximizes system reliability subject to maximum system cost and maximum system weight constraints is presented; secondly, a statistical analysis is used to optimize GA parameters, and thirdly GA is used to optimize series-parallel systems reliability. The objective is to determine the strategy choosing the redundancy level for each subsystem to maximize the overall system reliability subject to total cost and total weight constraints. Finally, the series-parallel system case study reliability optimization results are showed, and comparisons with the other previous results are presented to demonstrate the performance of our GA.

Keywords: reliability, optimization, meta-heuristic, genetic algorithm, redundancy

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Authors: Iman Zafarparandeh, Muzammil Mumtaz, Paniz Taherzadeh, Deniz Erbulut

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The instability in the atlantoaxial joint may occur due to cervical surgery, congenital anomalies, and trauma. There are different types of fixation techniques proposed for restoring the stability and preventing harmful neurological deterioration. Application of the screw constructs has become a popular alternative to the older techniques for stabilizing the joint. The main difference between the various screw constructs is the type of the screw which can be lateral mass screw, pedicle screw, transarticular screw, and translaminar screw. The aim of this paper is to study the effect of three popular screw constructs fixation techniques on the biomechanics of the atlantoaxial joint using the finite element (FE) method. A three-dimensional FE model of the upper cervical spine including the skull, C1 and C2 vertebrae, and groups of the existing ligaments were developed. The accurate geometry of the model was obtained from the CT data of a 35-year old male. Three screw constructs were designed to compare; Magerl transarticular screw (TA-Screw), Goel-Harms lateral mass screw and pedicle screw (LM-Screw and Pedicle-Screw), and Wright lateral mass screw and translaminar screw (LM-Screw and TL-Screw). Pure moments were applied to the model in the three main planes; flexion (Flex), extension (Ext), axial rotation (AR) and lateral bending (LB). The range of motion (ROM) of C0-C1 and C1-C2 segments for the implanted FE models are compared to the intact FE model and the in vitro study of Panjabi (1988). The Magerl technique showed less effect on the ROM of C0-C1 than the other two techniques in sagittal plane. In lateral bending and axial rotation, the Goel-Harms and Wright techniques showed less effect on the ROM of C0-C1 than the Magerl technique. The Magerl technique has the highest fusion rate as 99% in all loading directions for the C1-C2 segment. The Wright technique has the lowest fusion rate in LB as 79%. The three techniques resulted in the same fusion rate in extension loading as 99%. The maximum stress for the Magerl technique is the lowest in all load direction compared to other two techniques. The maximum stress in all direction was 234 Mpa and occurred in flexion with the Wright technique. The maximum stress for the Goel-Harms and Wright techniques occurred in lateral mass screw. The ROM obtained from the FE results support this idea that the fusion rate of the Magerl is more than 99%. Moreover, the maximum stress occurred in each screw constructs proves the less failure possibility for the Magerl technique. Another advantage of the Magerl technique is the less number of components compared to other techniques using screw constructs. Despite the benefits of the Magerl technique, there are drawbacks to using this method such as reduction of the C1 and C2 before screw placement. Therefore, other fixation methods such as Goel-Harms and Wright techniques find the solution for the drawbacks of the Magerl technique by adding screws separately to C1 and C2. The FE model implanted with the Wright technique showed the highest maximum stress almost in all load direction.

Keywords: cervical spine, finite element model, atlantoaxial, fixation technique

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Authors: Zinaida I. Ivanova, Olga V. Yudenkova

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The article addresses the pressing need to implement the principle of the biosphere compatibility as the core prerequisite for sustainable development. The co-authors argue that a careful attitude towards the biosphere, termination of its overutilization, analysis of the ratio between the biospheric potential of a specific area and its population numbers, coupled with population regulation techniques represent the factors that may solve the problems of ecological depletion. However these problems may only be tackled through the employment of the high-quality human capital, capable of acting with account for the principles of nature conservation.

Keywords: biosphere compatibility, eco-centered conscience, human capital, sustainable development

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Authors: Mohammad R. Irshidat, Mohammed H. Al-Saleh, Mahmoud Al-Shoubaki

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This paper investigates the viability of using carbon fiber reinforced epoxy composites modified with carbon nano tubes to strengthening reinforced concrete (RC) columns. Six RC columns was designed and constructed according to ASCE standards. The columns were wrapped using carbon fiber sheets impregnated with either neat epoxy or CNTs modified epoxy. These columns were then tested under concentric axial loading. Test results show that; compared to the unwrapped specimens; wrapping concrete columns with carbon fiber sheet embedded in CNTs modified epoxy resulted in an increase in its axial load resistance, maximum displacement, and toughness values by 24%, 109% and 232%, respectively. These results reveal that adding CNTs into epoxy resin enhanced the confinement effect, specifically, increased the axial load resistance, maximum displacement, and toughness values by 11%, 6%, and 19%, respectively compared with columns strengthening with carbon fiber sheet embedded in neat epoxy.

Keywords: CNT, epoxy, carbon fiber, RC columns

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Authors: Alireza Pouladkhan, Mohammad Yavari Foroushani, Ali Mortazavi

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This paper presents a finite element model for a sandwich plate containing a piezoelectric core. A sandwich plate with a piezoelectric core is constructed using the shear mode of piezoelectric materials. The orientation of poling vector has a significant effect on deflection and stress induced in the piezo-actuated adaptive sandwich plate. In the present study, the influence of this factor for a clamped-clamped-free-free and simple-simple-free-free square sandwich plate is investigated using Finite Element Method. The study uses ABAQUS (v.6.7) software to derive the finite element model of the sandwich plate. By using this model, the study gives the influences of the poling vector angle on the response of the smart structure and determines the maximum transverse displacement and maximum stress induced.

Keywords: finite element method, sandwich plate, poling vector, piezoelectric materials, smart structure, electric enthalpy

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Authors: Bhim Singh

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Due to increased pressure from global competitors, manufacturing organizations are switching over to lean philosophies from traditional mass production. Lean manufacturing is a manufacturing philosophy which focuses on elimination of various types of wastes and creates maximum value for the end customers. Lean thinking aims to produce high quality products and services at the lowest possible cost with maximum customer responsiveness. Indian Industry is facing lot of problems in this transformation from traditional mass production to lean production. Through this paper an attempt has been made to identify various lean implementation hurdles in Indian industries with the help of a structured survey. Identified hurdles are grouped with the help of factor analysis and rated by calculating descriptive statistics. To show the effect of lean implementation hurdles a hypothesis “Organizations having higher level of lean implementation hurdles will have poor (negative) performance” has been postulated and tested using correlation matrix between performance parameters of the organizations and identified hurdles. The findings of the paper will be helpful to prepare road map to identify and eradicate the lean implementation hurdles.

Keywords: factor analysis, global competition, lean implementation, lean hurdles

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Authors: Magdalena Twaruzek, Karolina Ropejko

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Mycotoxins are secondary metabolites of molds. Ochratoxin A (OTA) is the most common in the Polish climate. It is produced by fungi of the genera Aspergillus and Penicillium. It is produced as a result of improper food storage. It is present in many products that are consumed both by humans and animals: cereals, wheat gluten, coffee, dried fruit, wine, grape juice, spices, beer, and products based on them. OTA is nephrotoxic, hepatotoxic, potentially carcinogenic, and teratogenic. OTA mainly enters an organism by oral intake. The aim of the study was to detect the presence of OTA in milk, urine, and serum of lactating women. A survey was also conducted regarding the daily diet of women. The research group consisted of 32 lactating women (11 were the donors from the Milk Bank in Toruń, the other 21 were recruited for this study). Results of the analysis showed the occurrence of OTA only in 3 milk samples (9.38%). The minimum level was 0.01 ng/ml, while the maximum 0.018 ng/ml and the mean 0.0013 ng/ml. Twenty-six urine samples (81.25%) were OTA positive, with minimum level 0.013 ng/ml, maximum level 0.117 ng/ml and mean 0.0192 ng/ml. Also, all 32 serum samples (100%) were contaminated by OTA, with a minimum level of 0.099 ng/ml, a maximum level of 2.38 ng/ml, and a mean of 0.4649 ng/ml. In the case of 3 women, OTA was present in all tested body fluids. Based on the results, the following conclusions can be drawn: the breast-milk of women in the study group is slightly contaminated with ochratoxin A. Ten samples of urine contained ochratoxin A above its average content in tested samples. Moreover, serum of 8 women contains ochratoxin A at a level above the average content of this mycotoxin in tested samples. The average ochratoxin A level in serum in the presented studies was 0.4649 ng/ml, which is much lower than the average serum ochratoxin A level established in several countries in the world, i.e., 0.7 ng/ml. Acknowledgment: This study was supported by the Polish Minister of Science and Higher Education under the program 'Regional Initiative of Excellence' in 2019 - 2022 (Grant No. 008/RID/2018/19).

Keywords: breast-milk, urine, serum, contamination, ochratoxin A

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Authors: Firano Zakaria, Filali Adib Fatine

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The issue f convergence in theoretical models (classical or Keynesian) has been widely discussed. The results of the work affirm that most countries are seeking to get as close as possible to a steady state in order to catch up with developed countries. In this paper, we have retested this question whether it is absolute or conditional. The results affirm that the degree of convergence of countries like Morocco is very low and income is still far from its equilibrium state. Moreover, the analysis of financial convergence, of the countries in our panel, states that the pace in this sector is more intense: countries are converging more rapidly in financial terms. The question arises as to why, with a fairly convergent financial system, growth does not respond, yet the financial system should facilitate this economic convergence. Our results confirm that the degree of information exchange between the financial system and the economic system did not change significantly between 1985 and 2017. This leads to the hypothesis that the financial system is failing to serve its role as a creator of information in developing countries despite all the reforms undertaken, thus making the existence of an economic demon in the Maxwell prevail.

Keywords: economic convergence, financial convergence, financial system, entropy

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Authors: C. Bunsanit

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This paper presents the refinement method for two beams formation of wideband smart antenna. The refinement method for weighting coefficients is based on Fully Spatial Signal Processing by taking Inverse Discrete Fourier Transform (IDFT), and its simulation results are presented using MATLAB. The radiation pattern is created by multiplying the incoming signal with real weights and then summing them together. These real weighting coefficients are computed by IDFT method; however, the range of weight values is relatively wide. Therefore, for reducing this range, the refinement method is used. The radiation pattern concerns with five input parameters to control. These parameters are maximum weighting coefficient, wideband signal, direction of mainbeam, beamwidth, and maximum of minor lobe level. Comparison of the obtained simulation results between using refinement method and taking only IDFT shows that the refinement method works well for wideband two beams formation.

Keywords: fully spatial signal processing, beam forming, refinement method, smart antenna, weighting coefficient, wideband

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Authors: Auwal Garba, Rabiu Maijama’a, Abdullahi Muhammad Jalam

Abstract:

Variability in climate has affected the agricultural production all over the globe. This concern has motivated important changes in the field of research during the last decade. Climate variability is believed to have declining effects towards rice production in Nigeria. This study examined climate variability and its impact on rice productivity in Dass Local Government Area, Bauchi State, by employing Linear Trend Model (LTM), analysis of variance (ANOVA) and regression analysis. Annual seasonal data of the climatic variables for temperature (min. and max), rainfall, and solar radiation from 1990 to 2015 were used. Results confirmed that 74.4% of the total variation in rice yield in the study area was explained by the changes in the independent variables. That is to say, temperature (minimum and maximum), rainfall, and solar radiation explained rice yield with 74.4% in the study area. Rising mean maximum temperature would lead to reduction in rice production while moderate increase in mean minimum temperature would be advantageous towards rice production, and the persistent rise in the mean maximum temperature, in the long run, will have more negatively affect rice production in the future. It is, therefore, important to promote agro-meteorological advisory services, which will be useful in farm planning and yield sustainability. Closer collaboration among the meteorologist and agricultural scientist is needed to increase the awareness about the existing database, crop weather models among others, with a view to reaping the full benefits of research on specific problems and sustainable yield management and also there should be a special initiative by the ADPs (State Agricultural Development Programme) towards promoting best agricultural practices that are resilient to climate variability in rice production and yield sustainability.

Keywords: climate variability, impact, productivity, rice

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Authors: Hubert Klar

Abstract:

High double excitation of two-electron atoms has been investigated using hyperpherical coordinates within a modified adiabatic expansion technique. This modification creates a novel fictitious force leading to a spontaneous exchange symmetry breaking at high double excitation. The Pauli principle must therefore be regarded as approximation valid only at low excitation energy. Threshold electron scattering from high Rydberg states shows an unexpected time reversal symmetry breaking. At threshold for double escape we discover a broad (few eV) Cooper pair.

Keywords: correlation, resonances, threshold ionization, Cooper pair

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Authors: K. Anas, M. Selvakumar, Samson David, R. R. Babu, S. Chattopadhyay

Abstract:

The dynamic deformation of a visco elastic material can cause heat generation. This heat generation is aspect energy dissipation. The present work investigates the contribution of various factors like; elastomer structure, cross link type and density, filler networking, reinforcement potential and temperature at energy dissipation mechanism. The influences of these elements are investigated using very high frequency analyzer (VHF ) and dynamical mechanical analysis(DMA).VHF follows transmissibility and vibration isolation principle whereas DMA works on dynamical mechanical deformation principle. VHF analysis of different types of elastomers reveals that elastomer can act as a transmitter or damper of energy depending on the applied frequency ratio (ω/ωn). Dynamic modulus (G') of low damping rubbers like natural rubber does not varies rapidly with frequency but vice-versa for high damping rubber like butyl rubber (IIR). VHF analysis also depicts that polysulfidic linkages has high damping ratio (ζ) than mono sulfidic linkages due to its dissipative nature. At comparable cross link density, mono sulfidic linkages shows higher glass transition temperature (Tg) than poly sulfidic linkages. The intensity and location of loss modulus (G'') peak of different types of carbon black filled natural rubber compounds suggests that segmental relaxation at glass transition temperature (Tg) is seldom affected by filler particles, but the filler networks can influence the cross link density by absorbing the curatives. The filler network breaking and reformation during a dynamic strain is a thermally activated process. Thus, stronger aggregates are highly dissipative in nature. Measurements indicate that at lower temperature regimes polymeric chain friction is highly dissipative in nature.

Keywords: damping ratio, natural frequency, crosslinking density, segmental motion, surface activity, dissipative, polymeric chain friction

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Authors: Zian Cheak Tiu, Harith Ahmad, Sulaiman Wadi Harun

Abstract:

A simple multi-wavelength passively Q-switched Erbium-doped fiber laser (EDFL) is demonstrated using low cost multi-walled carbon nanotubes (MWCNTs) based saturable absorber (SA), which is prepared using polyvinyl alcohol (PVA) as a host polymer. The multi-wavelength operation is achieved based on nonlinear polarization rotation (NPR) effect by incorporating 50 m long photonic crystal fiber (PCF) in the ring cavity. The EDFL produces a stable multi-wavelength comb spectrum for more than 14 lines with a fixed spacing of 0.48 nm. The laser also demonstrates a stable pulse train with the repetition rate increases from 14.9 kHz to 25.4 kHz as the pump power increases from the threshold power of 69.0 mW to the maximum pump power of 133.8 mW. The minimum pulse width of 4.4 µs was obtained at the maximum pump power of 133.8 mW while the highest energy of 0.74 nJ was obtained at pump power of 69.0 mW.

Keywords: multi-wavelength Q-switched, multi-walled carbon nanotube, photonic crystal fiber

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Authors: Chad Goldsworthy, B. Rajeswari Matam

Abstract:

The use of deep learning for species identification in camera trap images has revolutionised our ability to study, conserve and monitor species in a highly efficient and unobtrusive manner, with state-of-the-art models achieving accuracies surpassing the accuracy of manual human classification. The high imbalance of camera trap datasets, however, results in poor accuracies for minority (rare or endangered) species due to their relative insignificance to the overall model accuracy. This paper investigates the use of Focal Loss, in comparison to the traditional Cross Entropy Loss function, to improve the identification of minority species in the “255 Bird Species” dataset from Kaggle. The results show that, although Focal Loss slightly decreased the accuracy of the majority species, it was able to increase the F1-score by 0.06 and improve the identification of the bottom two, five and ten (minority) species by 37.5%, 15.7% and 10.8%, respectively, as well as resulting in an improved overall accuracy of 2.96%.

Keywords: convolutional neural networks, data imbalance, deep learning, focal loss, species classification, wildlife conservation

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Authors: M. R. Zaman, M. S. Bari, M. Kajal

Abstract:

A field experiment was conducted at the Agroforestry and Environment Research Field, Hajee Mohammad Danesh Science and Technology University, Dinajpur during 2013 to investigate the potentiality of three napier fodder varieties under Litchi orchard. The experiment was consisted of 2 factors RCBD with 3 replications. Among the two factors, factor A was two production systems; S1= Litchi + fodder and S2 = Fodder (sole crop); another factor B was three napier varieties: V1= BARI Napier -1 (Bazra), V2= BARI Napier - 2 (Arusha) and V3= BARI Napier -3 (Hybrid). The experimental results revealed that there were significant variation among the varieties in terms of leaf growth and yield. The maximum number of leaf plant -1 was recorded in variety Bazra (V1) whereas the minimum number was recorded in hybrid variety (V3).Significantly the highest (13.75, 14.53 and14.84 tha-1 at 1st, 2nd and 3rd harvest respectively) yield was also recorded in variety Bazra whereas the lowest (5.89, 6.36 and 9.11 tha-1 at 1st, 2nd v and 3rd harvest respectively) yield was in hybrid variety. Again, in case of production systems, there were also significant differences between the two production systems were founded. The maximum number of leaf plant -1 was recorded under Litchi based AGF system (T1) whereas the minimum was recorded in open condition (T2). Similarly, significantly the highest (12.00, 12.35 and 13.31 tha-1 at 1st, 2nd and 3rd harvest respectively) yield of napier was recorded under Litchi based AGF system where as the lowest (9.73, 10.47 and 11.66 tha-1 at 1st, 2nd and 3rd harvest respectively) yield was recorded in open condition i.e. napier in sole cropping. Furthermore, the interaction effect of napier variety and production systems were also gave significant deviation result in terms of growth and yield. The maximum number of leaf plant -1 was recorded under Litchi based AGF systems with Bazra variety whereas the minimum was recorded in open condition with hybrid variety. The highest yield (14.42, 16.14 and 16.15 tha-1 at 1st, 2nd and 3rd harvest respectively) of napier was found under Litchi based AGF systems with Bazra variety. Significantly the lowest (5.33, 5.79 and 8.48 tha-1 at 1st, 2nd and 3rd harvest respectively) yield was found in open condition i.e. sole cropping with hybrid variety. In case of the quality perspective, the highest nutritive value (DM, ASH, CP, CF, EE, and NFE) was found in Bazra (V1) and the lowest value was found in hybrid variety (V3). Therefore, the suitability of napier production under Litchi based AGF system may be ranked as Bazra > Arusha > Hybrid variety. Finally, the economic analysis showed that maximum BCR (5.20) was found in the Litchi based AGF systems over sole cropping (BCR=4.38). From the findings of the taken investigation, it may be concluded that the cultivation of Bazra napier varieties in the floor of Litchi orchard ensures higher revenue to the farmers compared to its sole cropping.

Keywords: potentiality, Litchi, fodder, agroforestry

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Authors: Noor S. Nasri, Eric C. A. Tatt, Usman D. Hamza, Jibril Mohammed, Husna M. Zain

Abstract:

Climate change has becoming a global environmental issue that may trigger irreversible changes in the environment with catastrophic consequences for human, animals and plants on our planet. Methane, carbon dioxide and nitrous oxide are the greenhouse gases (GHG) and as the main factor that significantly contributes to the global warming. Mainly carbon dioxide be produced and released to atmosphere by thermal industrial and power generation sectors. Methane is dominant component of natural gas releases significant of thermal heat, and the gaseous pollutants when homogeneous thermal combustion takes place at high temperature. Heterogeneous catalytic Combustion (HCC) principle is promising technologies towards environmental friendly energy production should be developed to ensure higher yields with lower pollutants gaseous emissions and perform complete combustion oxidation at moderate temperature condition as comparing to homogeneous high thermal combustion. Hence the principle has become a very interesting alternative total oxidation for the treatment of pollutants gaseous emission especially NOX product formation. Noble metals are dispersed on a support-porous HCC such as γ- Al2O3, TiO2 and ThO2 to increase thermal stability of catalyst and to increase to effectiveness of catalytic combustion. Support-porous HCC material to be selected based on factors of the surface area, porosity, thermal stability, thermal conductivity, reactivity with reactants or products, chemical stability, catalytic activity, and catalyst life. γ- Al2O3 with high catalytic activity and can last longer life of catalyst, is commonly used as the support for Pd catalyst at low temperatures. Sustainable and renewable support-material of bio-mass char was derived from agro-industrial waste material and used to compare with those the conventional support-porous material. The abundant of biomass wastes generated in palm oil industries is one potential source to convert the wastes into sustainable material as replacement of support material for catalysts. Objective of this study was to compare the kinetic rate of reaction the combustion of methane on Palladium (Pd) based catalyst with Al2O3 support and bio-char (Bc) support derived from shell kernel. The 2wt% Pd was prepared using incipient wetness impregnation method and the HCC performance was accomplished using tubular quartz reactor with gas mixture ratio of 3% methane and 97% air. Material characterization was determined using TGA, SEM, and BET surface area. The methane porous-HCC conversion was carried out by online gas analyzer connected to the reactor that performed porous-HCC. BET surface area for prepared 2 wt% Pd/Bc is smaller than prepared 2wt% Pd/ Al2O3 due to its low porosity between particles. The order of catalyst activity based on kinetic rate on reaction of catalysts in low temperature is prepared 2wt% Pd/Bc > calcined 2wt% Pd/ Al2O3 > prepared 2wt% Pd/ Al2O3 > calcined 2wt% Pd/Bc. Hence the usage of agro-industrial bio-mass waste material can enhance the sustainability principle.

Keywords: catalytic-combustion, environmental, support-bio-char material, sustainable and renewable material

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