Search results for: loss of load expectation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6140

Search results for: loss of load expectation

5540 Design and Study of a DC/DC Converter for High Power, 14.4 V and 300 A for Automotive Applications

Authors: Júlio Cesar Lopes de Oliveira, Carlos Henrique Gonçalves Treviso

Abstract:

The shortage of the automotive market in relation to options for sources of high power car audio systems, led to development of this work. Thus, we developed a source with stabilized voltage with 4320 W effective power. Designed to the voltage of 14.4 V and a choice of two currents: 30 A load option in battery banks and 300 A at full load. This source can also be considered as a source of general use dedicated commercial with a simple control circuit in analog form based on discrete components. The assembly of power circuit uses a methodology for higher power than the initially stipulated.

Keywords: DC-DC power converters, converters, power conversion, pulse width modulation converters

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5539 Vertical Uplift Capacity of a Group of Equally Spaced Helical Screw Anchors in Sand

Authors: Sanjeev Mukherjee, Satyendra Mittal

Abstract:

This paper presents the experimental investigations on the behaviour of a group of single, double and triple helical screw anchors embedded vertically at the same level in sand. The tests were carried out on one, two, three and four numbers of anchors in sand for different depths of embedment keeping shallow and deep mode of behaviour in mind. The testing program included 48 tests conducted on three model anchors installed in sand whose density kept constant throughout the tests. It was observed that the ultimate pullout load varied significantly with the installation depth of the anchor and the number of anchors. The apparent coefficient of friction (f*) between anchor and soil was also calculated based on the test results. It was found that the apparent coefficient of friction varies between 1.02 and 4.76 for 1, 2, 3, and 4 numbers of single, double and triple helical screw anchors. Plate load tests conducted on model soil showed that the value of ф increases from 35o for virgin soil to 48o for soil with four double screw helical anchors. The graphs of ultimate pullout capacity of a group of two, three and four no. of anchors with respect to one anchor were plotted and design equations have been proposed correlating them. Based on these findings, it has been concluded that the load-displacement relationships for all groups can be reduced to a common curve. A 3-D finite element model, PLAXIS, was used to confirm the results obtained from laboratory tests and the agreement is excellent.

Keywords: apparent coefficient of friction, helical screw anchor, installation depth, plate load test

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5538 Possibilities of Psychodiagnostics in the Context of Highly Challenging Situations in Military Leadership

Authors: Markéta Chmelíková, David Ullrich, Iva Burešová

Abstract:

The paper maps the possibilities and limits of diagnosing selected personality and performance characteristics of military leadership and psychology students in the context of coping with challenging situations. Individuals vary greatly inter-individually in their ability to effectively manage extreme situations, yet existing diagnostic tools are often criticized mainly for their low predictive power. Nowadays, every modern army focuses primarily on the systematic minimization of potential risks, including the prediction of desirable forms of behavior and the performance of military commanders. The context of military leadership is well known for its life-threatening nature. Therefore, it is crucial to research stress load in the specific context of military leadership for the purpose of possible anticipation of human failure in managing extreme situations of military leadership. The aim of the submitted pilot study, using an experiment of 24 hours duration, is to verify the possibilities of a specific combination of psychodiagnostic to predict people who possess suitable equipment for coping with increased stress load. In our pilot study, we conducted an experiment of 24 hours duration with an experimental group (N=13) in the bomb shelter and a control group (N=11) in a classroom. Both groups were represented by military leadership students (N=11) and psychology students (N=13). Both groups were equalized in terms of study type and gender. Participants were administered the following test battery of personality characteristics: Big Five Inventory 2 (BFI-2), Short Dark Triad (SD-3), Emotion Regulation Questionnaire (ERQ), Fatigue Severity Scale (FSS), and Impulsive Behavior Scale (UPPS-P). This test battery was administered only once at the beginning of the experiment. Along with this, they were administered a test battery consisting of the Test of Attention (d2) and the Bourdon test four times overall with 6 hours ranges. To better simulate an extreme situation – we tried to induce sleep deprivation - participants were required to try not to fall asleep throughout the experiment. Despite the assumption that a stay in an underground bomb shelter will manifest in impaired cognitive performance, this expectation has been significantly confirmed in only one measurement, which can be interpreted as marginal in the context of multiple testing. This finding is a fundamental insight into the issue of stress management in extreme situations, which is crucial for effective military leadership. The results suggest that a 24-hour stay in a shelter, together with sleep deprivation, does not seem to simulate sufficient stress for an individual, which would be reflected in the level of cognitive performance. In the context of these findings, it would be interesting in future to extend the diagnostic battery with physiological indicators of stress, such as: heart rate, stress score, physical stress, mental stress ect.

Keywords: bomb shelter, extreme situation, military leadership, psychodiagnostic

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5537 Erosion Susceptibility Zoning and Prioritization of Micro-Watersheds: A Remote Sensing-Gis Based Study of Asan River Basin, Western Doon Valley, India

Authors: Pijush Roy, Vinay Kumar Rai

Abstract:

The present study highlights the estimation of soil loss and identification of critical area for implementation of best management practice is central to the success of soil conservation programme. The quantification of morphometric and Universal Soil Loss Equation (USLE) factors using remote sensing and GIS for prioritization of micro-watersheds in Asan River catchment, western Doon valley at foothills of Siwalik ranges in the Dehradun districts of Uttarakhand, India. The watershed has classified as a dendritic pattern with sixth order stream. The area is classified into very high, high, moderately high, medium and low susceptibility zones. High to very high erosion zone exists in the urban area and agricultural land. Average annual soil loss of 64 tons/ha/year has been estimated for the watershed. The optimum management practices proposed for micro-watersheds of Asan River basin are; afforestation, contour bunding suitable sites for water harvesting structure as check dam and soil conservation, agronomical measure and bench terrace.

Keywords: erosion susceptibility zones, morphometric characteristics, prioritization, remote sensing and GIS, universal soil loss equation

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5536 Prioritized Processor-Sharing with a Maximum Permissible Sojourn Time

Authors: Yoshiaki Shikata

Abstract:

A prioritized processor-sharing (PS) system with a maximum permissible sojourn time (MPST) is proposed. In this PS system, a higher-priority request is allocated a larger service ratio than a lower-priority request. Moreover, each request receiving service is guaranteed the maximum permissible sojourn time determined by each priority class, regardless of its service time. Arriving requests that cannot receive service due to this guarantee are rejected. We further propose a guarantee method for implementing such a system, and discuss performance evaluation procedures for the resulting system. Practical performance measures, such as the relationships between the loss probability or mean sojourn time of each class request and the maximum permissible sojourn time are evaluated via simulation. At the arrival of each class request, its acceptance or rejection is judged using extended sojourn times of all requests receiving service in the server. As the MPST increases, the mean sojourn time increases almost linearly. However, the logarithm of the loss probability decreases almost linearly. Moreover with an MPST, the difference in the mean sojourn time for different MPSTs increases with the traffic rate. Conversely, the difference in the loss probability for different MPSTs decreases as the traffic rate increases.

Keywords: prioritized processor sharing, priority ratio, permissible sojourn time, loss probability, mean sojourn time, simulation

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5535 Transverse Vibration of Elastic Beam Resting on Variable Elastic Foundation Subjected to moving Load

Authors: Idowu Ibikunle Albert, Atilade Adesanya Oluwafemi, Okedeyi Abiodun Sikiru, Mustapha Rilwan Adewale

Abstract:

These present-day all areas of transport have experienced large advances characterized by increases in the speeds and weight of vehicles. As a result, this paper considered the Transverse Vibration of an Elastic Beam Resting on a Variable Elastic Foundation Subjected to a moving Load. The beam is presumed to be uniformly distributed and has simple support at both ends. The moving distributed moving mass is assumed to move with constant velocity. The governing equations, which are fourth-order partial differential equations, were reduced to second-order partial differential equations using an analytical method in terms of series solution and solved by a numerical method using mathematical software (Maple). Results show that an increase in the values of beam parameters, moving Mass M, and k-stiffness K, significantly reduces the deflection profile of the vibrating beam. In the results, it was equally found that moving mass is greater than moving force.

Keywords: elastic beam, moving load, response of structure, variable elastic foundation

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5534 Fracture and Dynamic Behavior of Leaf Spring Suspension

Authors: S. Lecheb, A. Chellil, H. Mechakra, S. Attou, H. Kebir

Abstract:

Although leaf springs are one of the oldest suspension components they are still frequently used, especially in commercial vehicles. Being able to capture the leaf spring characteristics is of significant importance for vehicle handling dynamics studies. The main function of leaf spring is not only to support vertical load but also to isolate road induced vibrations. It is subjected to millions of load cycles leading to fatigue failure. It needs to have excellent fatigue life. The objective of this work is its use of Abaqus software to locate the most stressed areas and predict the areas in which it occurs in fatigue and crack of leaf spring and calculate the stress and frequencies of this model.

Keywords: leaf spring, crack, stress, natural frequencies

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5533 Comparison of Gait Variability in Individuals with Trans-Tibial and Trans-Femoral Lower Limb Loss: A Pilot Study

Authors: Hilal Keklicek, Fatih Erbahceci, Elif Kirdi, Ali Yalcin, Semra Topuz, Ozlem Ulger, Gul Sener

Abstract:

Objectives and Goals: The stride-to-stride fluctuations in gait is a determinant of qualified locomotion as known as gait variability. Gait variability is an important predictive factor of fall risk and useful for monitoring the effects of therapeutic interventions and rehabilitation. Comparison of gait variability in individuals with trans-tibial lower limb loss and trans femoral lower limb loss was the aim of the study. Methods: Ten individuals with traumatic unilateral trans femoral limb loss(TF), 12 individuals with traumatic transtibial lower limb loss(TT) and 12 healthy individuals(HI) were the participants of the study. All participants were evaluated with treadmill. Gait characteristics including mean step length, step length variability, ambulation index, time on each foot of participants were evaluated with treadmill. Participants were walked at their preferred speed for six minutes. Data from 4th minutes to 6th minutes were selected for statistical analyses to eliminate learning effect. Results: There were differences between the groups in intact limb step length variation, time on each foot, ambulation index and mean age (p < .05) according to the Kruskal Wallis Test. Pairwise analyses showed that there were differences between the TT and TF in residual limb variation (p=.041), time on intact foot (p=.024), time on prosthetic foot(p=.024), ambulation index(p = .003) in favor of TT group. There were differences between the TT and HI group in intact limb variation (p = .002), time on intact foot (p<.001), time on prosthetic foot (p < .001), ambulation index result (p < .001) in favor of HI group. There were differences between the TF and HI group in intact limb variation (p = .001), time on intact foot (p=.01) ambulation index result (p < .001) in favor of HI group. There was difference between the groups in mean age result from HI group were younger (p < .05).There were similarity between the groups in step lengths (p>.05) and time of prosthesis using in individuals with lower limb loss (p > .05). Conclusions: The pilot study provided basic data about gait stability in individuals with traumatic lower limb loss. Results of the study showed that to evaluate the gait differences between in different amputation level, long-range gait analyses methods may be useful to get more valuable information. On the other hand, similarity in step length may be resulted from effective prosthetic using or effective gait rehabilitation, in conclusion, all participants with lower limb loss were already trained. The differences between the TT and HI; TF and HI may be resulted from the age related features, therefore, age matched population in HI were recommended future studies. Increasing the number of participants and comparison of age-matched groups also recommended to generalize these result.

Keywords: lower limb loss, amputee, gait variability, gait analyses

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5532 Computational Modeling of Load Limits of Carbon Fibre Composite Laminates Subjected to Low-Velocity Impact Utilizing Convolution-Based Fast Fourier Data Filtering Algorithms

Authors: Farhat Imtiaz, Umar Farooq

Abstract:

In this work, we developed a computational model to predict ply level failure in impacted composite laminates. Data obtained from physical testing from flat and round nose impacts of 8-, 16-, 24-ply laminates were considered. Routine inspections of the tested laminates were carried out to approximate ply by ply inflicted damage incurred. Plots consisting of load–time, load–deflection, and energy–time history were drawn to approximate the inflicted damages. Impact test generated unwanted data logged due to restrictions on testing and logging systems were also filtered. Conventional filters (built-in, statistical, and numerical) reliably predicted load thresholds for relatively thin laminates such as eight and sixteen ply panels. However, for relatively thick laminates such as twenty-four ply laminates impacted by flat nose impact generated clipped data which can just be de-noised using oscillatory algorithms. The literature search reveals that modern oscillatory data filtering and extrapolation algorithms have scarcely been utilized. This investigation reports applications of filtering and extrapolation of the clipped data utilising fast Fourier Convolution algorithm to predict load thresholds. Some of the results were related to the impact-induced damage areas identified with Ultrasonic C-scans and found to be in acceptable agreement. Based on consistent findings, utilizing of modern data filtering and extrapolation algorithms to data logged by the existing machines has efficiently enhanced data interpretations without resorting to extra resources. The algorithms could be useful for impact-induced damage approximations of similar cases.

Keywords: fibre reinforced laminates, fast Fourier algorithms, mechanical testing, data filtering and extrapolation

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5531 A Numerical and Experimental Study on Fast Pyrolysis of Single Wood Particle

Authors: Hamid Rezaei, Xiaotao Bi, C. Jim Lim, Anthony Lau, Shahab Sokhansanj

Abstract:

A one-dimensional heat transfer model coupled with the kinetic information has been used to predict the overall pyrolysis mass loss of a single wood particle. The kinetic parameters were determined experimentally and the regime and characteristics of the conversion were evaluated in terms of the particle size and reactor temperature. The order of overall mass loss changed from n=1 at temperatures lower than 350 °C to n=0.5 at temperatures higher that 350 °C. Conversion time analysis showed that particles larger than 0.5 mm were controlled by internal thermal resistances. The valid range of particle size to use the simplified lumped model depends on the fluid temperature around the particles. The critical particle size was 0.6-0.7 mm for the fluid temperature of 500 °C and 0.9-1.0 mm for the fluid temperature of 100 °C. Experimental pyrolysis of moist particles did not show distinct drying and pyrolysis stages. The process was divided into two hypothetical drying and pyrolysis dominated zones and empirical correlations are developed to predict the rate of mass loss in each zone.

Keywords: pyrolysis, kinetics, model, single particle

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5530 Alternating Expectation-Maximization Algorithm for a Bilinear Model in Isoform Quantification from RNA-Seq Data

Authors: Wenjiang Deng, Tian Mou, Yudi Pawitan, Trung Nghia Vu

Abstract:

Estimation of isoform-level gene expression from RNA-seq data depends on simplifying assumptions, such as uniform reads distribution, that are easily violated in real data. Such violations typically lead to biased estimates. Most existing methods provide a bias correction step(s), which is based on biological considerations, such as GC content–and applied in single samples separately. The main problem is that not all biases are known. For example, new technologies such as single-cell RNA-seq (scRNA-seq) may introduce new sources of bias not seen in bulk-cell data. This study introduces a method called XAEM based on a more flexible and robust statistical model. Existing methods are essentially based on a linear model Xβ, where the design matrix X is known and derived based on the simplifying assumptions. In contrast, XAEM considers Xβ as a bilinear model with both X and β unknown. Joint estimation of X and β is made possible by simultaneous analysis of multi-sample RNA-seq data. Compared to existing methods, XAEM automatically performs empirical correction of potentially unknown biases. XAEM implements an alternating expectation-maximization (AEM) algorithm, alternating between estimation of X and β. For speed XAEM utilizes quasi-mapping for read alignment, thus leading to a fast algorithm. Overall XAEM performs favorably compared to other recent advanced methods. For simulated datasets, XAEM obtains higher accuracy for multiple-isoform genes, particularly for paralogs. In a differential-expression analysis of a real scRNA-seq dataset, XAEM achieves substantially greater rediscovery rates in an independent validation set.

Keywords: alternating EM algorithm, bias correction, bilinear model, gene expression, RNA-seq

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5529 Application of Artificial Neural Network and Background Subtraction for Determining Body Mass Index (BMI) in Android Devices Using Bluetooth

Authors: Neil Erick Q. Madariaga, Noel B. Linsangan

Abstract:

Body Mass Index (BMI) is one of the different ways to monitor the health of a person. It is based on the height and weight of the person. This study aims to compute for the BMI using an Android tablet by obtaining the height of the person by using a camera and measuring the weight of the person by using a weighing scale or load cell. The height of the person was estimated by applying background subtraction to the image captured and applying different processes such as getting the vanishing point and applying Artificial Neural Network. The weight was measured by using Wheatstone bridge load cell configuration and sending the value to the computer by using Gizduino microcontroller and Bluetooth technology after the amplification using AD620 instrumentation amplifier. The application will process the images and read the measured values and show the BMI of the person. The study met all the objectives needed and further studies will be needed to improve the design project.

Keywords: body mass index, artificial neural network, vanishing point, bluetooth, wheatstone bridge load cell

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5528 Load Bearing Capacity and Operational Effectiveness of Single Shear Joints of CFRP Composite Laminate with Spread Tow Thin Plies

Authors: Tabrej Khan, Tamer A. Sebaey, Balbir Singh, M. A. Umarfarooq

Abstract:

Spread-tow thin-ply-based technology has resulted in the progress of optimized reinforced composite plies with ultra-low thicknesses. There is wide use of composite bolted joints in the aircraft industry for load-bearing structures, and they are regarded as the primary source of stress concentration. The purpose of this study is to look into the bearing strength and structural performance of single shear bolt joint configurations in composite laminates, which are basically a combination of conventional thin-plies and thick-plies in some specific stacking sequence. The placement effect of thin-ply within the configured stack on bearing strength, as well as the potential damages, were investigated. Mechanical tests were used to understand the disfigurement mechanisms of the plies and their reciprocity, as well as to reflect on the single shear bolt joint properties and its load-bearing capacity. The results showed that changing the configuration of laminates by inserting the thin plies inside improved the bearing strength by up to 19%.

Keywords: hybrid composites, delamination, stress concentrations, mechanical testing, single bolt joint, thin-plies

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5527 Stabilization of Fly Ash Slope Using Plastic Recycled Polymer and Finite Element Analysis Using Plaxis 3D

Authors: Tushar Vasant Salunkhe, Sariput M. Nawghare, Maheboobsab B. Nadaf, Sushovan Dutta, J. N. Mandal

Abstract:

The model tests were conducted in the laboratory without and with plastic recycled polymer in fly ash steep slopes overlaying soft foundation soils like fly ash and power soil in order to check the stability of steep slope. In this experiment, fly ash is used as a filling material, and Plastic Recycled Polymers of diameter = 3mm and length = 4mm were made from the waste plastic product (lower grade plastic product). The properties of fly ash and plastic recycled polymers are determined. From the experiments, load and settlement have measured. From these data, load–settlement curves have been reported. It has been observed from test results that the load carrying capacity of mixture fly ash with Plastic Recycled Polymers slope is more than that of fly ash slope. The deformation of Plastic Recycled Polymers slope is slightly more than that of fly ash slope. A Finite Element Method (F.E.M.) was also evaluated using PLAXIS 3D version. The failure pattern, deformations and factor of safety are reported based on analytical programme. The results from experimental data and analytical programme are compared and reported.

Keywords: factor of safety, finite element method (FEM), fly ash, plastic recycled polymer

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5526 Evaluation of Prestressed Reinforced Concrete Slab Punching Shear Using Finite Element Method

Authors: Zhi Zhang, Liling Cao, Seyedbabak Momenzadeh, Lisa Davey

Abstract:

Reinforced concrete (RC) flat slab-column systems are commonly used in residential or office buildings, as the flat slab provides efficient clearance resulting in more stories at a given height than regular reinforced concrete beam-slab system. Punching shear of slab-column joints is a critical component of two-way reinforced concrete flat slab design. The unbalanced moment at the joint is transferred via slab moment and shear forces. ACI 318 provides an equation to evaluate the punching shear under the design load. It is important to note that the design code considers gravity and environmental load when considering the design load combinations, while it does not consider the effect from differential foundation settlement, which may be a governing load condition for the slab design. This paper describes how prestressed reinforced concrete slab punching shear is evaluated based on ACI 318 provisions and finite element analysis. A prestressed reinforced concrete slab under differential settlements is studied using the finite element modeling methodology. The punching shear check equation is explained. The methodology to extract data for punching shear check from the finite element model is described and correlated with the corresponding code provisions. The study indicates that the finite element analysis results should be carefully reviewed and processed in order to perform accurate punching shear evaluation. Conclusions are made based on the case studies to help engineers understand the punching shear behavior in prestressed and non-prestressed reinforced concrete slabs.

Keywords: differential settlement, finite element model, prestressed reinforced concrete slab, punching shear

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5525 Numerical Study of Dynamic Buckling of Fiber Metal Laminates's Profile

Authors: Monika Kamocka, Radoslaw Mania

Abstract:

The design of Fiber Metal Laminates - combining thin aluminum sheets and prepreg layers, allows creating a hybrid structure with high strength to weight ratio. This feature makes FMLs very attractive for aerospace industry, where thin-walled structures are commonly used. Nevertheless, those structures are prone to buckling phenomenon. Buckling could occur also under static load as well as dynamic pulse loads. In this paper, the problem of dynamic buckling of open cross-section FML profiles under axial dynamic compression in the form of pulse load of finite duration is investigated. In the numerical model, material properties of FML constituents were assumed as nonlinear elastic-plastic aluminum and linear-elastic glass-fiber-reinforced composite. The influence of pulse shape was investigated. Sinusoidal and rectangular pulse loads of finite duration were compared in two ways, i.e. with respect to magnitude and force pulse. The dynamic critical buckling load was determined based on Budiansky-Hutchinson, Ari Gur, and Simonetta dynamic buckling criteria.

Keywords: dynamic buckling, dynamic stability, Fiber Metal Laminate, Finite Element Method

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5524 Loss Minimization by Distributed Generation Allocation in Radial Distribution System Using Crow Search Algorithm

Authors: M. Nageswara Rao, V. S. N. K. Chaitanya, K. Amarendranath

Abstract:

This paper presents an optimal allocation and sizing of Distributed Generation (DG) in Radial Distribution Network (RDN) for total power loss minimization and enhances the voltage profile of the system. The two main important part of this study first is to find optimal allocation and second is optimum size of DG. The locations of DGs are identified by Analytical expressions and crow search algorithm has been employed to determine the optimum size of DG. In this study, the DG has been placed on single and multiple allocations.CSA is a meta-heuristic algorithm inspired by the intelligent behavior of the crows. Crows stores their excess food in different locations and memorizes those locations to retrieve it when it is needed. They follow each other to do thievery to obtain better food source. This analysis is tested on IEEE 33 bus and IEEE 69 bus under MATLAB environment and the results are compared with existing methods.

Keywords: analytical expression, distributed generation, crow search algorithm, power loss, voltage profile

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5523 Cycads Bark Harvest in Limpopo Province in South Africa: A Negative Practice Contributing to Biodiversity Loss

Authors: S. O. Bamigboye, P. M. Tshisikhawe, P. J. Taylor

Abstract:

Cycads are the most threatened plant species in the world. In South Africa over 70% of cycads are threatened with extinction with 60% of them as a result of bark harvest of these highly endangered species for medicinal purposes. 3 cycads species in South Africa have gone extinct due to bark harvest for medicinal purpose. This practice keeps increasing biodiversity loss within the nation and this has generated concern for conservationists on different way to discover how people go about this practices and how it can be discouraged. Studies have revealed this practice to be common practice in provinces like Kwazulu natal, Eastern cape, Gauteng, Mpumalanga, but studies in the past have not really focused on cycads bark harvest in Limpopo province. In this study we use the indigenous knowledge to discover a particular location within the Soutpansberg Montane (a major biodiversity hotspot in Limpopo Province in South Africa) in Vhembe district in Limpopo province not yet conserved where we have a highly disturbed population of cycads. Several individuals of cycads species have been highly damaged due to bark harvest in this location. We are about proposing that such areas needs attention for conservation to prevent the loss of these species endemic to this particular location. Our study hereby reveals that cycads bark harvest which is a major threat to African cycads is also a common practice in Limpopo Province in South Africa. Rigorous conservation action is required to discourage this practice in order to prevent further biodiversity loss in this region.

Keywords: bark harvest, Cycads, conservation, extinction, Limpopo

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5522 Modelling the Effect of Biomass Appropriation for Human Use on Global Biodiversity

Authors: Karina Reiter, Stefan Dullinger, Christoph Plutzar, Dietmar Moser

Abstract:

Due to population growth and changing patterns of production and consumption, the demand for natural resources and, as a result, the pressure on Earth’s ecosystems are growing. Biodiversity mapping can be a useful tool for assessing species endangerment or detecting hotspots of extinction risks. This paper explores the benefits of using the change in trophic energy flows as a consequence of the human alteration of the biosphere in biodiversity mapping. To this end, multiple linear regression models were developed to explain species richness in areas where there is no human influence (i.e. wilderness) for three taxonomic groups (birds, mammals, amphibians). The models were then applied to predict (I) potential global species richness using potential natural vegetation (NPPpot) and (II) global ‘actual’ species richness after biomass appropriation using NPP remaining in ecosystems after harvest (NPPeco). By calculating the difference between predicted potential and predicted actual species numbers, maps of estimated species richness loss were generated. Results show that biomass appropriation for human use can indeed be linked to biodiversity loss. Areas for which the models predicted high species loss coincide with areas where species endangerment and extinctions are recorded to be particularly high by the International Union for Conservation of Nature and Natural Resources (IUCN). Furthermore, the analysis revealed that while the species distribution maps of the IUCN Red List of Threatened Species used for this research can determine hotspots of biodiversity loss in large parts of the world, the classification system for threatened and extinct species needs to be revised to better reflect local risks of extinction.

Keywords: biodiversity loss, biomass harvest, human appropriation of net primary production, species richness

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5521 The Phosphatidate Phosphatase Pah1 and Its Regulator Nem1/spo7 Protein Phosphatase Required for Nucleophagy

Authors: Muhammad Arifur Rahman, Talukdar M. Waliullah, Takashi Ushimaru

Abstract:

Nucleophagy selectively degrades nuclear materials, especially nucleolus after nutrient starvation or inactivation of TORC1 kinase in budding yeast. Budding yeast phosphatidate (PA) phosphatase Pah1 that converts PA to diacylglycerol is essential for partitioning of lipid precursors between membrane and storage that is crucial for many aspects of cell growth and development. Pah1 is required for nuclear/ER membrane biogenesis and vacuole function, but whether Pah1 and its activator Nem1/Spo7 protein phosphatase complex are involved in autophagy is largely unknown. Loss of Pah1 causes expansion of the nucleus and fragmentation of the vacuole. Here we show that Pah1 is required for bulk autophagy and nucleophagy after TORC1 inactivation. Loss of Pah1 impaired nucleophagy severely and bulk autophagy to a lesser extent. Loss of the Pah1 activator Nem1-Spo7 protein phosphatase exhibited similar features.

Keywords: autophagy, Nem1/Spo7 phosphatase, Pah1, nucleophagy, TORC1

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5520 Proposed Location of Grid Connected Wind-Pv Hybrid System Based on Load Flow and Voltage Stability Indices Study

Authors: Bazilah Ismail, Muhammad Mat Naain, Ibrahim Alhamrouni, Lilik Jamilatul Awalin, Fadi Albatsh, Mohd Fairuz Abdul Hamid

Abstract:

Rapid depletion and prices of the conventional energy sources have stimulated the development of the renewable energy source (RES). Due to the unpredicted and intermittent nature of RES, the hybrid renewable energy system (HRES) is the best solution to complement the nature of the respective sources, and the combination of the wind and solar energy is rapidly gaining popularity. The significant challenges on the operation and planning of the grid system with a high HRES penetration has become an important subject since the location of HRES plant give impact towards the existing system. This paper aims to propose the location of the grid connected Wind-PV hybrid plant (WPHP) based on load flow and voltage stability indices study. Several case studies are carried out using IEEE 14 bus system, and the system is modeled and tested in DigSILENT PowerFactory.

Keywords: hybrid renewable energy system, wind farm, photovoltaic system, voltage stability and load flow

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5519 Skew Planar Wheel Antenna for First Person View of Unmanned Aerial Vehicle

Authors: Raymond Yudhi Purba, Levy Olivia Nur, Radial Anwar

Abstract:

This research presents the design and measurement of a skew planar wheel antenna that is used to visualize the first person view perspective of unmanned aerial vehicles. The antenna has been designed using CST Studio Suite 2019 to have voltage standing wave ratio (VSWR) ≤ 2, return loss ≤ -10 dB, bandwidth ≥ 100 MHz to covering outdoor access point band from 5.725 to 5.825 GHz, omnidirectional radiation pattern, and elliptical polarization. Dimensions of skew planar wheel antenna have been modified using parameter sweep technique to provide good performances. The simulation results provide VSWR 1.231, return loss -19.693 dB, bandwidth 828.8 MHz, gain 3.292 dB, and axial ratio 9.229 dB. Meanwhile, the measurement results provide VSWR 1.237, return loss -19.476 dB, bandwidth 790.5 MHz, gain 3.2034 dB, and axial ratio 4.12 dB.

Keywords: skew planar wheel, cloverleaf, first-person view, unmanned aerial vehicle, parameter sweep

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5518 The Experiences of Hong Kong Chinese Divorced Wives in Facing the Cancer Death of Their Ex-Husbands

Authors: M. L. Yeung

Abstract:

With the surge of divorce rate and male cancer onset/death rates, the phenomenon of divorced wives in the facing cancer death of their ex-husbands is not uncommon in Hong Kong. Yet, there is a dearth of study on the experiences of bereaved-divorced wives in the Hong Kong cultural context. This project fills the knowledge gap by conducting a qualitative study for having interviewed four bereaved ex-wives, who returned to ex-husbands’ end-of-life caregiving and eventually grieved for the ex-spousal’s death. From the perspectives of attachment theory and disenfranchised grief in the Hong Kong cultural context, a ‘double-loss’ experience is found in which interviewees suffer from the first loss of divorce and the second loss of ex-husbands’ death. Traumatic childhood experiences, attachment needs, role ambiguity, unresolved emotions and unrecognized grief are found significant in their lived experiences which alert the ‘double-loss’ is worthy of attention. Extending a family-centered end-of-life and bereavement care services to divorced couples is called for, in which validation on the attachment needs, ex-couple reconciliation, and acknowledgement on the disenfranchised grief are essential for social work practice on this group of clienteles specifically in Hong Kong cultural context.

Keywords: changing family, disenfranchised grief, divorce, ex-spousal death, marriage

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5517 The Decline of Verb-Second in the History of English: Combining Historical and Theoretical Explanations for Change

Authors: Sophie Whittle

Abstract:

Prior to present day, English syntax historically exhibited an inconsistent verb-second (V2) rule, which saw the verb move to the second position in the sentence following the fronting of a type of phrase. There was a high amount of variation throughout the history of English with regard to the ordering of subject and verb, and many explanations attempting to account for this variation have been documented in previous literature. However, these attempts have been contradictory, with many accounts positing the effect of previous syntactic changes as the main motivations behind the decline of V2. For instance, morphosyntactic changes, such as the loss of clitics and the loss of empty expletives, have been loosely connected to changes in frequency for the loss of V2. The questions surrounding the development of non-V2 in English have, therefore, yet to be answered. The current paper aims to bring together a number of explanations from different linguistic fields to determine the factors driving the changes in English V2. Using historical corpus-based methods, the study analyses both quantitatively and qualitatively the changes in frequency for the history of V2 in the Old, Middle, and Modern English periods to account for the variation in a range of sentential environments. These methods delve into the study of information structure, prosody and language contact to explain variation within different contexts. The analysis concludes that these factors, in addition to changes within the syntax, are responsible for the position of verb movement. The loss of V2 serves as an exemplar study within the field of historical linguistics, which combines a number of factors in explaining language change in general.

Keywords: corpora, English, language change, mixed-methods, syntax, verb-second

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5516 Nonlinear Finite Element Modeling of Unbonded Steel Reinforced Concrete Beams

Authors: Fares Jnaid, Riyad Aboutaha

Abstract:

In this paper, a nonlinear Finite Element Analysis (FEA) was carried out using ANSYS software to build a model able of predicting the behavior of Reinforced Concrete (RC) beams with unbonded reinforcement. The FEA model was compared to existing experimental data by other researchers. The existing experimental data consisted of 16 beams that varied from structurally sound beams to beams with unbonded reinforcement with different unbonded lengths and reinforcement ratios. The model was able to predict the ultimate flexural strength, load-deflection curve, and crack pattern of concrete beams with unbonded reinforcement. It was concluded that when the when the unbonded length is less than 45% of the span, there will be no decrease in the ultimate flexural strength due to the loss of bond between the steel reinforcement and the surrounding concrete regardless of the reinforcement ratio. Moreover, when the reinforcement ratio is relatively low, there will be no decrease in ultimate flexural strength regardless of the length of unbond.

Keywords: FEA, ANSYS, unbond, strain

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5515 Non-Destructive Test of Bar for Determination of Critical Compression Force Directed towards the Pole

Authors: Boris Blostotsky, Elia Efraim

Abstract:

The phenomenon of buckling of structural elements under compression is revealed in many cases of loading and found consideration in many structures and mechanisms. In the present work the method and results of dynamic test for buckling of bar loaded by a compression force directed towards the pole are considered. Experimental determination of critical force for such system has not been made previously. The tested object is a bar with semi-rigid connection to the base at one of its ends, and with a hinge moving along a circle at the other. The test includes measuring the natural frequency of the bar at different values of compression load. The lateral stiffness is calculated based on natural frequency and reduced mass on the bar's movable end. The critical load is determined by extrapolation the values of lateral stiffness up to zero value. For the experimental investigation the special test-bed was created that allows the stability testing at positive and negative curvature of the movable end's trajectory, as well as varying the rotational stiffness of the other end connection. Decreasing a friction at the movable end allows extend the diapason of applied compression force. The testing method includes: - Methodology of the experiment planning, that allows determine the required number of tests under various loads values in the defined range and the type of extrapolating function; - Methodology of experimental determination of reduced mass at the bar's movable end including its own mass; - Methodology of experimental determination of lateral stiffness of uncompressed bar rotational semi-rigid connection at the base. For planning the experiment and for comparison of the experimental results with the theoretical values of critical load, the analytical dependencies of lateral stiffness of the bar with defined end conditions on compression load. In the particular case of perfectly rigid connection of the bar to the base, the critical load value corresponds to solution by S.P. Timoshenko. Correspondence of the calculated and experimental values was obtained.

Keywords: non-destructive test, buckling, dynamic method, semi-rigid connections

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5514 Modeling Binomial Dependent Distribution of the Values: Synthesis Tables of Probabilities of Errors of the First and Second Kind of Biometrics-Neural Network Authentication System

Authors: B. S.Akhmetov, S. T. Akhmetova, D. N. Nadeyev, V. Yu. Yegorov, V. V. Smogoonov

Abstract:

Estimated probabilities of errors of the first and second kind for nonideal biometrics-neural transducers 256 outputs, the construction of nomograms based error probability of 'own' and 'alien' from the mathematical expectation and standard deviation of the normalized measures Hamming.

Keywords: modeling, errors, probability, biometrics, neural network, authentication

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5513 Weight Loss Degradation of Hybrid Blends LLDPE/Starch/PVA Upon Exposure to UV Light and Soil Burial

Authors: Rahmah M., Noor Zuhaira Abd Aziz, Farhan M., Mohd Muizz Fahimi M.

Abstract:

Polybag and mulch film for agricultural field pose environmental wastage upon disposal. Thus a degradable polybag was designed with hybrid sago starch (SS) and polyvinyl alcohol (PVA). Two Different blended composition of SS and PVA Hybrid have been compounded. Then, the hybrids blended are mixed with linear line density polyethylene (LLDPE) resin to fabricate polybag film through conventional film blowing process. Hybrid blends was compounded at different ratios. Samples of LLDPE, SS and PVA hybrid film were exposed to UV light and soil burial. The weight loss were determined during degradation process. Hybrid film by degradation of starch was found to decrease on esterification. However the hybrid film showed greater degradation in soil and uv radiation up to 60% of SS. Weight loss were also determined in control humidity oven with 70% humidity and temperature set up at 30 °C and left in humidity chamber for a month.

Keywords: LLDPE, PVA, sago starch, degradation, soil burial, uv radiation

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5512 Laboratory Testing Regime for Quantifying Soil Collapsibility

Authors: Anne C. Okwedadi, Samson Ng’ambi, Ian Jefferson

Abstract:

Collapsible soils go through radical rearrangement of their particles when triggered by water, stress or/and vibration, causing loss of volume. This loss of volume in soil as seen in foundation failures has caused millions of dollars’ worth of damages to public facilities and infrastructure and so has an adverse effect on the society and people. Despite these consequences and the several studies that are available, more research is still required in the study of soil collapsibility. Discerning the pedogenesis (formation) of soils and investigating the combined effects of the different geological soil properties is key to elucidating and quantifying soils collapsibility. This study presents a novel laboratory testing regime that would be undertaken on soil samples where the effects of soil type, compactive variables (moisture content, density, void ratio, degree of saturation) and loading are analyzed. It is anticipated that results obtained would be useful in mapping the trend of the combined effect thus the basis for evaluating soil collapsibility or collapse potentials encountered in construction with volume loss problems attributed to collapse.

Keywords: collapsible soil, geomorphological process, soil collapsibility properties, soil test

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5511 Elastoplastic Collapse Analysis of Pipe Bends Using Finite Element Analysis

Authors: Tawanda Mushiri, Charles Mbohwa

Abstract:

When an external load is applied to one of its ends, a pipe’s bends cross section tends to deform significantly both in and out of its end plane. This shell type behaviour characteristic of pipe bends and mainly due to their curves geometry accounts for their greater flexibility. This added flexibility is also accompanied by stressed and strains that are much higher than those present in a straight pipe. The primary goal of this research is to study the elastic-plastic behaviour of pipe bends under out of plane moment loading. It is also required to study the effects of changing the value of the pipe bend factor and the value of the internal pressure on that behaviour and to determine the value of the limit moments in each case. The results of these analyses are presented in the form of load deflection plots for each load case belonging to each model. From the load deflection curves, the limit moments of each case are obtained. The limit loads are then compared to those computed using some of the analytical and empirical equation available in the literature. The effects of modelling parameters are also studied. The results obtained from small displacement and large displacement analyses are compared and the effects of using a strain hardened material model are also investigated. To better understand the behaviour of pipe elbows under out of plane bending and internal pressure, it was deemed important to know how the cross section deforms and to study the distribution of stresses that cause it to deform in a particular manner. An elbow with pipe bend factor h=0.1 to h=1 is considered and the results of the detailed analysis are thereof examined.

Keywords: elasto-plastic, finite element analysis, pipe bends, simulation

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