Search results for: chip scale

Authors: J. Hrabovský, M. Chabičovský, J. Horský

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Water spray cooling is a technique typically used in heat treatment and other metallurgical processes where controlled temperature regimes are required. Water spray cooling is used in static (without movement) or dynamic (with movement of the steel plate) regimes. The static regime is notable for the fixed position of the hot steel plate and fixed spray nozzle. This regime is typical for quenching systems focused on heat treatment of the steel plate. The second application of spray cooling is the dynamic regime. The dynamic regime is notable for its static section cooling system and moving steel plate. This regime is used in rolling and finishing mills. The fixed position of cooling sections with nozzles and the movement of the steel plate produce nonhomogeneous water distribution on the steel plate. The length of cooling sections and placement of water nozzles in combination with the nonhomogeneity of water distribution leads to discontinued or interrupted cooling conditions. The impact of static and dynamic regimes on cooling intensity and the heat transfer coefficient during the cooling process of steel plates is an important issue. Heat treatment of steel is accompanied by oxide scale growth. The oxide scale layers can significantly modify the cooling properties and intensity during the cooling. The combination of the static and dynamic (section) regimes with the variable thickness of the oxide scale layer on the steel surface impact the final cooling intensity. The study of the influence of the oxide scale layers with different cooling regimes was carried out using experimental measurements and numerical analysis. The experimental measurements compared both types of cooling regimes and the cooling of scale-free surfaces and oxidized surfaces. A numerical analysis was prepared to simulate the cooling process with different conditions of the section and samples with different oxide scale layers.

Keywords: heat transfer coefficient, numerical analysis, oxide layer, spray cooling

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Authors: S. P. Singh

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This paper measures technical and scale efficiencies of 40 Indian sugar companies for the period from 2004-05 to 2013-14. The efficiencies are estimated through input-oriented DEA models using one output variable—value of output (VOP) and five input variables—capital cost (CA), employee cost (EMP), raw material (RW), energy & fuel (E&F) and other manufacturing expenses (OME). The sugar companies are classified into integrated and non-integrated categories to know which one achieves higher level of efficiency. Sources of inefficiency in the industry are identified through decomposing the overall technical efficiency (TE) into pure technical efficiency (PTE) and scale efficiency (SE). The paper also estimates input-reduction targets for relatively inefficient companies and suggests measures to improve their efficiency level. The findings reveal that the TE does not evince any trend rather it shows fluctuations across years, largely due to erratic and cyclical pattern of sugar production. Further, technical inefficiency in the industry seems to be driven more by the managerial inefficiency than the scale inefficiency, which implies that TE can be improved through better conversion of inputs into output.

Keywords: DEA, slacks, sugar industry, technical efficiency

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Authors: Lan Du, Yan Wang, Hui Dai

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Synthetic aperture radar (SAR) image change detection has recently become a challenging problem owing to the existence of speckle noises. In this paper, an unsupervised distribution-free change detection for SAR image based on scale-invariant feature transform (SIFT) keypoints and segmentation is proposed. Firstly, the noise-robust SIFT keypoints which reveal the blob-like structures in an image are extracted in the log-ratio image to reduce the detection range. Then, different from the traditional change detection which directly obtains the change-detection map from the difference image, segmentation is made around the extracted keypoints in the two original multitemporal SAR images to obtain accurate changed region. At last, the change-detection map is generated by comparing the two segmentations. Experimental results on the real SAR image dataset demonstrate the effectiveness of the proposed method.

Keywords: change detection, Synthetic Aperture Radar (SAR), Scale-Invariant Feature Transformation (SIFT), segmentation

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Authors: Zhenjie Liu

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This paper investigates the existence and uniqueness of solutions for singular higher order boundary value problems on time scales by using mixed monotone method. The theorems obtained are very general. For the different time scale, the problem may be the corresponding continuous or discrete boundary value problem.

Keywords: mixed monotone operator, boundary value problem, time scale, green's function, positive solution, singularity

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Authors: Nesrin Demir, Betül Demirbağ

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In recent years, the type and content of bullying in schools changes together with technological development. Many studies attribute bullying movement to virtual platform to the widespread use of social media and internet. The main goal of this research is to determine if there is a correlation between subjective well-being as a popular conception of Positive Psychology and being cyber bully/victim. For this purpose, 287 students from various public high schools in Malatya have reached. As assessment tool, Cyber Bully/Victim Scale and Self Well Being Scale for Adolescents were used. Results were discussed in the relevant literature.

Keywords: cyber bully, cyber victim, school counseling, subjective well-being

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Authors: Stephanie Watson, Fabrice Stephenson, Conrad Pilditch, Carolyn Lundquist

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Spatial data detailing both the distribution and density of functionally important marine species are needed to inform management decisions. Species distribution models (SDMs) have proven helpful in this regard; however, models often focus only on species occurrences derived from spatially expansive datasets and lack the resolution and detail required to inform regional management decisions. Boosted regression trees (BRT) were used to produce high-resolution SDMs (250 m) at two spatial scales predicting probability of occurrence, abundance (count per sample unit), density (count per km2) and uncertainty for seven coastal seafloor taxa that vary in habitat usage and distribution to examine prediction differences and implications for coastal management. We investigated if small scale regionally focussed models (82,000 km2) can provide improved predictions compared to data-rich national scale models (4.2 million km2). We explored the variability in predictions across model type (occurrence vs abundance) and model scale to determine if specific taxa models or model types are more robust to geographical variability. National scale occurrence models correlated well with broad-scale environmental predictors, resulting in higher AUC (Area under the receiver operating curve) and deviance explained scores; however, they tended to overpredict in the coastal environment and lacked spatially differentiated detail for some taxa. Regional models had lower overall performance, but for some taxa, spatial predictions were more differentiated at a localised ecological scale. National density models were often spatially refined and highlighted areas of ecological relevance producing more useful outputs than regional-scale models. The utility of a two-scale approach aids the selection of the most optimal combination of models to create a spatially informative density model, as results contrasted for specific taxa between model type and scale. However, it is vital that robust predictions of occurrence and abundance are generated as inputs for the combined density model as areas that do not spatially align between models can be discarded. This study demonstrates the variability in SDM outputs created over different geographical scales and highlights implications and opportunities for managers utilising these tools for regional conservation, particularly in data-limited environments.

Keywords: Benthic ecology, spatial modelling, multi-scalar modelling, marine conservation.

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Authors: Ummuhan Bas Aslan, Sehmus Aslan

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Objective: Physical disability includes impairments, activity limitations, and participation restrictions. Individuals with physical disabilities have lower self-esteem compared non-disabled people. Self-esteem is widely accepted as a key indicator of emotional stability and adjustment to life demands. There is very limited study to investigate the effect of sports on self-esteem in physically disabled people. The aim of the present study was to evaluate of self-esteem in physically disabled adults who participated in sports. Methods: Fifty physically disabled adults who participated in sports aged between 18 to 35 years participated in the study. Self-esteem of the participants was assessed by Rosenberg Self-Esteem Scale. The scale is a 10-item measure of global self-esteem. The higher score on the scale indicates greater self-esteem. Scores between 15 and 25 are the normal range of and scores below 15 suggest low self-esteem. Results: Average age of participants was 25.18±6.20 years. 58% of the participants were 23 (46.0%) of the participants were wheelchair users, 8 (16.0%) were mobile with a walking aid and 19 (38.0%) were mobile without a walking aid. The length of physically disabled adults had been participating in their sports (basketball: 54%, athleticism: 32%, volleyball: 6%, cycling: 6%) was 4.94±3.86 years. The average Rosenberg Self-Esteem Scale score of the participants was 21.88 ±4.34. Conclusions: Our results suggest that physically disabled adults who participated in sports have the healthy level of self-esteem. Participating in sports could have positive effects on self-esteem in that physically, disabled people. There is needed future comparative studies on this topic.

Keywords: adult, physical disability, self-esteem, sport

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Authors: Anas H. Aljemely, Jianping Xuan

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Rolling bearing fault diagnosis plays a pivotal issue in the rotating machinery of modern manufacturing. In this research, a raw vibration signal and improved deep learning method for bearing fault diagnosis are proposed. The multi-dimensional scales of raw vibration signals are selected for evaluation condition monitoring system, and the deep learning process has shown its effectiveness in fault diagnosis. In the proposed method, employing an Exponential linear unit (ELU) layer in a convolutional neural network (CNN) that conducts the identical function on positive data, an exponential nonlinearity on negative inputs, and a particular convolutional operation to extract valuable features. The identification results show the improved method has achieved the highest accuracy with a 100-dimensional scale and increase the training and testing speed.

Keywords: bearing fault prognostics, developed CNN model, multiple-scale evaluation, deep learning features

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Authors: Yuan-Hong Ho, Chiung-Ju Huang

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This article presents a monitoring indicators system that predicts whether a local government in Taiwan is heading for fiscal distress and identifies a suitable fiscal policy that would allow the local government to achieve fiscal balance in the long run. This system is relevant to stockholders’ interest, simple for national audit bodies to use, and provides an early warning of fiscal distress that allows preventative action to be taken.

Keywords: fiscal health, fiscal distress, monitoring signals, 10-point scale

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Authors: M. Arunachalam, M. Pandey

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Nacre, a biological material that forms the inner-layer of sea shells can achieve high toughness and strength by way of staggered arrangement of strong tablets with soft and weak organic interface. Under applied loads the tablets slide over the adjacent tablets, thus generating inelastic deformation and toughness on macroscopic scale. A two dimensional finite element based homogenization methodology is adopted for obtaining the effective material properties of Nacre using a representative volume element (RVE) at finite deformations. In this work, the material behaviour for tablet and interface are assumed to be Isotropic elastic and Isotropic elastic-perfectly plastic with strain softening respectively. Numerical experiments such as uniaxial tension test along X, Y directions and simple shear test are performed on the RVE with uniform displacement and periodic constraints applied at the RVE boundaries to obtain the anisotropic homogenized response and maximum local stresses within each constituents of Nacre. Homogenized material model is then tested for macroscopic structure under three point bending condition and the results obtained are comparable with the results obtained for detailed microstructure based structure, thus homogenization provides a bridge between macroscopic scale and microscopic scale and homogenized material properties obtained from microstructural (RVE) analysis could be used in large scale structural analysis.

Keywords: finite element, homogenization, inelastic deformation, staggered arrangement

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Authors: M. Priscila Ramos, Omar O. Chisari, Juan Pablo Vila Martínez

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Current literature about trade liberalization of environmental goods and services (EGS) raises doubts about the extent of the triple win-win situation for trade, development and the environment. However, much of this literature does not consider the possibility that this agreement carries technological transmissions, either through trade or foreign direct investment. This paper presents a computable general equilibrium model calibrated for Argentina, where there are alternative technologies (one dirty and one clean according to carbon emissions) to produce the same goods. In this context, the trade liberalization of EGS allows to increase GDP, trade, reduce unemployment and improve the households welfare. However, the capital mobility appears as the key assumption to jointly reach the environmental target, when the positive scale effect generated by the increase in trade is offset by the change in the composition of production (composition and technical effects by the use of the clean alternative technology) and of consumption (composition effect by substitution of relatively lesspolluting imported goods).

Keywords: CGE modeling, CO2 emissions, composition effect, scale effect, technique effect, trade liberalization of EGS

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Authors: Yun-Ru Tsai, Jo-Hui Lin

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The cultural interactions between tourists and destination communities have received increased attention. Tourists play an important role in constructing a rewarding intercultural experience and cultural understanding. Cultural literacy is the ability for tourists to negotiate different cultures, this research aimed to develop a measurement of Tourist Cultural Literacy (TCL), the result provides a theoretical framework to assess how tourists interact with different cultural destinations. A pilot qualitative research was conducted in order to generate the initial items. In this study, the procedure of developing the TCL scale was divided into two parts. First, an exploratory factor analysis was conducted, a 25-item TCL scale was developed and six factors were identified: cultural sensitivity, appreciation of the culture, respect for the culture, knowledge of the culture, participate in the culture, and empathy for the culture. Second, confirmatory factor analyses and structural equation modeling were employed, the six-factor model was verified, and was proven to have good fit, reliability, convergent validity, discriminant validity, and criterion-related validity. The study provides managerial implications for tourist management and education, the popularization of TCL might increase the respect and understanding between tourists and local societies as well as decrease the cultural shocks and negative social-cultural impacts derived from tourism activities, thereby reducing the maintenance cost of management and allowing tourists to obtain a better cultural experience. Future research suggestions are also provided.

Keywords: cultural literacy, cultural tourism, scale development, tourism contact

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Authors: Sneha Samal, Iva Petrikova, Bohdana Marvalova

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Influence of grain size, shape and grain boundary diffusion at high temperature oxidation of pure metal is investigated as the function of microstructure evolution in this article. The oxidized scale depends on the geometrical parameter of the metal-scale system and grain shape, size, diffusion through boundary layers and influence of the contamination. The creation of the inner layer and the morphological structure develops from the internal stress generated during the growth of the scale. The oxidation rate depends on the cation and anion mobile transport of the metal in the inward and outward direction of the diffusion layer. Oxidation rate decreases with decreasing the grain size of the pure metal, whereas zinc deviates from this principle. A strong correlation between the surface roughness evolution, grain size, crystalline properties and oxidation mechanism of the oxidized metal was established.

Keywords: high temperature oxidation, pure metals, grain size, shape and grain boundary

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Authors: Maryam Kiani, Abdul Basit Kiani

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At larger scales, the performance of cementitious materials is impacted by processes occurring at the nanometer scale. These materials boast intricate hierarchical structures with random features that span from the nanometer to millimeter scale. It is fascinating to observe how the nanoscale processes influence the overall behavior and characteristics of these materials. By delving into and manipulating these processes, scientists and engineers can unlock the potential to create more durable and sustainable infrastructure and construction materials. It's like unraveling a hidden tapestry of secrets that hold the key to building stronger and more resilient structures. The present work employs simulations as the computational modeling methodology to predict mechanical properties for carbon/silica based cementitious materials at the molecular/nano scale level. Studies focused on understanding the effect of higher mechanical properties of cementitious materials with carbon silica nanoparticles via Material Studio materials modeling.

Keywords: nanomaterials, SiO₂, carbon black, mechanical properties

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Authors: Tri Harianto, Lawalenna Samang, St. Hijraini Nur, Arwin

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Recently, a port development is constructed in Makassar city, South Sulawesi Province, Indonesia. Makassar city is located in lowland area that dominated by soft marine clay deposit. A two kilometers causeway construction was built which is situated on the soft clay layer. In order to investigate the behavior of causeway embankment, a full-scale test was conducted of high embankment built on a soft clay deposit. The embankment with 3,5 m high was supported by two types of reinforcement such as raft and raft-aggregate column foundation. Since the ground was undergoing consolidation due to the preload, the raft and raft-aggregate column foundations were monitored in order to analyze the vertical ground movement by inducing the settlement of the foundation. In this study, two types of foundation (raft and raft-aggregate column) were tested to observe the effectiveness of raft-aggregate column compare to raft foundation in reducing the settlement. The settlement monitored during the construction stage by using the settlement plates, which is located in the center and toe of the embankment. Measurements were taken every day for each embankment construction stage (4 months). In addition, an analytical calculation was conducted in this study to compare the full-scale test result. The result shows that the raft-aggregate column foundation significantly reduces the settlement by 30% compared to the raft foundation. A raft-aggregate column foundation also reduced the time period of each loading stage. The Good agreement of analytical calculation compared to the full-scale test result also found in this study.

Keywords: full-scale, preloading, raft-aggregate column, soft clay

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Authors: İsmail Seçer

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Although depression and anxiety disorders are considered to be adult disorders, the evidence obtained from several studies conducted recently shows that the roots of depression and anxiety disorders go back to childhood years. Thus, it is thought that analyzing depressive symptoms and anxiety disorders observed in the childhood is an important necessity. In the direction of the problem status of the study, the purpose of this study is to adapt anxiety and depression questionnaire for children into Turkish culture and analyze the psychometric characteristics of it on clinical and nonclinical samples separately. The study is a descriptive survey research. The study was conducted on two different sample groups, clinical and nonclinical. The clinical sample is formed of 205 individuals and the nonclinical sample is formed of 630 individuals. Through the study, anxiety and depression questionnaire for children, anxiety sensitivity index and obsessive compulsive disorder questionnaire for children were used. Experts’ opinions were asked to provide language validity of the scale. Confirmatory factor analysis and criterion-related validity to analyze construct validity and internal consistency and split-half reliability analyses were done for reliability. In the direction of experts’ opinions, construct validity of the scale was analyzed with simple confirmatory factor analysis and it was determined that the model fit of the two-factor structure of the scale gives good fit on both the clinical and nonclinical samples after determining that the language validity of the scale is provided. In criterion-related validity, it was determined that there are positive and significant relations between anxiety and depression questionnaire for children and anxiety sensitivity and obsessive compulsive disorder. The results of internal consistency and half-split reliability analyses also show that the scale has adequate reliability value. It can be said that depression and anxiety questionnaire for children which was adapted to determine depressive symptoms and anxiety disorders observed in childhood has adequate reliability and validity values and it can be used in future studies. It can be recommended that the psychometric characteristics of the scale can be analyzed and reported on new samples in the future studies.

Keywords: scale adapting, construct validity, confirmatory factor analysis, childhood depression

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Authors: C. Pallis

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Induced-Gravity inflation is a model of chaotic inflation where the inflaton is identified with a Higgs-like modulus whose the vacuum expectation value controls the gravitational strength. Thanks to a strong enough coupling between the inflaton and the Ricci scalar curvature, inflation is attained even for subplanckian values of the inflaton with the corresponding effective theory being valid up to the Planck scale. In its simplest realization, induced-gravity inflation is based on a quatric potential and a quadratic non-minimal coupling and the inflationary observables turn out to be in agreement with the Planck data. Its supersymmetrization can be formulated within no-scale Supergravity employing two gauge singlet chiral superfields and applying a continuous $R$ and a discrete Zn symmetry to the proposed superpotential and Kahler potential. Modifying slightly the non-minimal coupling to Gravity, the model can account for the recent results of BICEP2. These modifications can be also accommodated beyond the no-scale SUGRA considering the fourth order term of the Kahler potential which mixes the inflaton with the accompanying non-inflaton field and small deviations from the prefactor $-3$ encountered in the adopted Kahler potential.

Keywords: cosmology, supersymmetric models, supergravity, modified gravity

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Authors: Zuhair Kadhim Jahanger, S. Joseph Antony

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The available studies in the literature which dealt with the scale effects of strip footings on different sand packing systematically still remain scarce. In this research, the variation of ultimate bearing capacity and deformation pattern of soil beneath strip footings of different widths under plane-strain condition on the surface of loose, medium-dense and dense sand have been systematically studied using experimental and noninvasive methods for measuring microscopic deformations. The presented analyses are based on model scale compression test analysed using Particle Image Velocimetry (PIV) technique. Upper bound analysis of the current study shows that the maximum vertical displacement of the sand under the ultimate load increases for an increase in the width of footing, but at a decreasing rate with relative density of sand, whereas the relative vertical displacement in the sand decreases for an increase in the width of the footing. A well agreement is observed between experimental results for different footing widths and relative densities. The experimental analyses have shown that there exists pronounced scale effect for strip surface footing. The bearing capacity factors Nγ rapidly decrease up to footing widths B=0.25 m, 0.35 m, and 0.65 m for loose, medium-dense and dense sand respectively, after that there is no significant decrease in Nγ. The deformation modes of the soil as well as the ultimate bearing capacity values have been affected by the footing widths. The obtained results could be used to improve settlement calculation of the foundation interacting with granular soil.

Keywords: DPIV, granular mechanics, scale effect, upper bound analysis

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Authors: Jan Doutreloigne

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This paper describes two methods for the reduction of the peak input current during the boosting of Dickson charge pumps. Both methods are implemented in the fully integrated Dickson charge pumps of a high-voltage display driver chip for smart-card applications. Experimental results reveal good correspondence with Spice simulations and show a reduction of the peak input current by a factor of 6 during boosting

Keywords: bi-stable display driver, Dickson charge pump, high-voltage generator, peak current reduction, sub-pump boosting, variable frequency boosting

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Authors: Kwadwo Afari Gyan

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Cities are growing at unprecedented levels. Meanwhile, governments in the Global South are already overwhelmed by this growth and are unable to provide infrastructure proactively as expected. As a result, urban residents resort to providing their own infrastructure, such as drainage systems, as part of self-built housing development. Their small-scale, incremental housing practices, which often represent the formation of dense and diverse housing types, styles, and ages, have been identified to affect the planning of drainage systems at the regional scale. Such developments reflect the varied, affordable responses as part of a collective effort to curb regional problems, specifically flooding in this case. However, while some are included in this collective action, others are excluded as they are unable to afford to be included. This phenomenon, in addition to the formation of new autonomous localities, has led to challenges in mitigating flooding and has affected resilience to climate change. Using a qualitative approach, this paper explores how the mismatch between housing development, which occurs at an individual scale, and drainage infrastructure, which is provided at a regional scale, affects a regional effort to mitigate flooding in Tema, Ghana. It seeks to explore and reveal a relationship between affordability and inclusiveness. It also explores how density and diversity influence public infrastructure provision and their connection with affordability.

Keywords: climate change, affordability, inclusivity, equity, contextualization, regionalism

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Authors: Ankit Shai

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CRC or Cyclic Redundancy Check is one of the most common, and one of the most powerful error-detecting codes implemented on modern computers. Most of the modern communication protocols use some error detection algorithms in digital networks and storage devices to detect accidental changes to raw data between transmission and reception. Cyclic Redundancy Check, or CRC, is the most popular one among these error detection codes. CRC properties are defined by the generator polynomial length and coefficients. The aim of this project is to implement an efficient FPGA based CRC-8 that accepts a 32 bit input, taking into consideration optimal chip area and high performance, using VHDL. The proposed architecture is implemented on Xilinx ISE Simulator. It is designed while keeping in mind the hardware design, complexity and cost factor.

Keywords: cyclic redundancy checker, CRC-8, 32-bit input, FPGA, VHDL, ModelSim, Xilinx

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Authors: Andrey A. Chernousov, Ben Y. B. Chan

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The thermal behavior of a large-scale, phase change material (PCM) enhanced building envelope system was studied in regard to the need for pre-fabricated construction in subtropical regions. The proposed large-scale envelope consists of a reinforced aluminum skin, insulation core, phase change material and reinforced gypsum board. The PCM impact on an energy efficiency of an enveloped room was resolved by validation of the Energy Plus numerical scheme and optimization of a smart material location in the core. The PCM location was optimized by a minimization method of a cooling energy demand. It has been shown that there is good agreement between the test and simulation results. The optimal location of the PCM layer in Hong Kong summer conditions has been then recomputed for core thicknesses of 40, 60 and 80 mm. A non-dimensional value of the optimal PCM location was obtained to be same for all the studied cases and the considered external and internal conditions.

Keywords: thermal performance, phase change material, energy efficiency, PCM optimization

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Authors: Intan Izafina Idrus, Mardina Abdullah, Alina Marie Hasbi, Asnawi Husin

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This paper presents the result of large-scale traveling ionospheric disturbance (LSTID) observation during moderate magnetic storm event on 25 October 2011 with SYM-H ~ -160 nT and Kp ~ 7 over Peninsular Malaysia at equatorial region using vertical total electron content (VTEC) from the Global Positioning System (GPS) observation measurement. The propagation of the LSTID signatures in the TEC measurements over Peninsular Malaysia was also investigated using VTEC map. The LSTID was found to propagate equator-ward during this event. The results showed that the LSTID propagated with an average phase velocity of 526.41 m/s and average periods of 140 min. The occurrence of this LSTID was also found to be the subsequent effects of substorm activities in the auroral region.

Keywords: Global Positioning System (GPS), large-scale traveling ionospheric disturbance (LSTID), moderate geomagnetic storm, vertical total electron content (VTEC)

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Authors: Meril Kate Mariano, Billy Joel Almarinez Divina Amalin, Jose Isagani Janairo

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The scale insects Aspidiotus destructor and Aspidiotus rigidus exhibit notable scale covers made of wax which provides protection against water loss and is capable to resist wetting, thus making them a desirable model for biomimetic designs. Their waxy covers enable them to infest mainly leaves of coconut trees despite the harsh wind and rain. This study aims to describe and compare the micro morphological characters on the surfaces of their scale covers consequently, how these micro structures affect their wetting properties. Scanning electron microscope was used for the surface characterization while an optical contact angle meter was employed in the wetting measurement. The scale cover of A. destructor is composed of multiple overlapping layers of wax that is arranged regularly while that of A. rigidus is composed of a uniform layer of wax with much more prominent wax ribbons irregularly arranged compared to the former. The protrusions found on the two organisms are formed by the wax ribbons that differ in arrangement with their height being A. destructor (3.57+1.29) < A. rigidus (4.23+1.22) and their density A. destructor (15+2.94) < A. rigidus (18.33+2.64). These morphological measurements could affect the contact angle (CA θ) measurement of A. destructor (102.66+9.78°) < A. rigidus (102.77 + 11.01°) wherein the assessment that the interaction of the liquid to the microstructures of the substrate is a large factor in the wetting properties of the insect scales is realized. The calculated surface free energy of A. destructor (38.47 mJ/m²) > A. rigidus (31.02 mJ/m²) shows inverse proportionality with the CA measurement. The dispersive interaction between the surface and liquid is more prevalent compared to the polar interaction for both Aspidiotus species, which was observed using the Fowkes method. The results of this study have possible applications to be a potential biomimetic design for various industries such as textiles and coatings.

Keywords: Aspidiotus spp., biomimetics, contact angle, surface characterization, wetting behavior

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Authors: Shehret Tilvaldyev, Jorge Flores-Garay, Alfredo Villanueva, Erwin Martinez, Lazaro Rico

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The efficiency of modern transportation is severely compromised by the prevalence of turbulent drag. The high level of turbulent skin-friction occurring, e.g., on the surface of an aircraft, automobiles or the carriage of a high-speed train, is responsible for excess fuel consumption and increased carbon emissions. The environmental, political, and economic pressure to improve fuel efficiency and reduce carbon emissions associated with transportation means that reducing turbulent skin-friction drag is a pressing engineering problem. The dynamic pressure of subsonic airflow around solid objects creates lift, but also induces drag force. This paper is presenting the results of laboratory experiments, investigating appearance and magnitude of dynamic pressure in micro scale of subsonic air flow around right cylinder and symmetrical airfoil.

Keywords: airflow, dynamic pressure, micro scale, symmetric object

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Authors: Akram Farhadi, Mahshid Froughan, Farahnaz Mohammadi, Maryam Rassouli, Maryam Noroozian, Leila Sadeghmoghaddam

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Background: The caregivers’ assessment of their own caregiving is considered the most important concept in exploring their experiences and has a major role in care outcomes. The rising number of people with dementia and their need for care makes family caregiving really important matter to consider and evaluate. Objectives: This study was conducted with the aim to naturalize and validate the Persian version of the Revised Caregiving Appraisal Scale (RCAS) in family caregivers of older adults with dementia. Patients and Method: In this cross-sectional methodological study, the Revised Caregiving Appraisal Scale (RCAS) was translated using International Quality of Life Assessment (IQOLA) protocol, and then a panel of experts examined its face and content validities. To ensure construct validity, the translated Revised Caregiving Appraisal Scale (RCAS) was completed by 236 family caregivers, and factor construct of the scale was assessed with 5 initial factors using confirmatory factor analysis. Internal consistency was found using Cronbach's alpha, and test-retest using intraclass correlation coefficient. Confirmatory factor analysis was performed in LISREL-8.8 software in Windows®. Results: Participating caregivers' mean age was 53.5±13.13 years. Content and face validities of the scale were confirmed according to the views expressed by family caregivers and panel of experts. The confirmatory factor analysis (CFA) results showed appropriate values for all fitness indices (RMSEA=0.046, df/X2=2.428, CFI=0.98, AGFI=0.84, GFI=0.9), and the 5-factor model was confirmed with 27 items. Overall Cronbach's alpha was reported 0.894, and test retest showed overall ICC=0.94. Conclusion: The Persian version of RCAS is a valid and reliable tool for family caregivers' assessment of their caregiving of older adults with dementia, and can be useful in assessing family caregiving interventions.

Keywords: psychometric, family caregivers, reliability and validity, elderly, dementia, self-appraisal

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Authors: Ryan Dale B. Elnar

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This study developed a multidimensional need assessment scale for college students called The University of Mindanao Needs Assessment Scale (UMNAS). Although there are context-specific instruments measuring the needs of clinical and non-clinical samples, literature reveals no standardized scales to measure the needs of the college students thus a four-phase item development process was initiated to support its content validity. Comprising seven broad facets namely spiritual-moral, intrapersonal, socio-personal, psycho-emotional, cognitive, physical and sexual, a pyramid model of college needs was deconstructed through FGD sample to support the literature review. Using various construct validity procedures, the model was further tested using a total of 881 Filipino college samples. The result of the study revealed evidences of the reliability and validity of the UMNAS. The reliability indices range from .929-.933. Exploratory and confirmatory factor analyses revealed a one-factor-six-dimensional instrument to measure the needs of the college students. Using multivariate regression analysis, year level and course are found predictors of students’ needs. Content analysis attested the usefulness of the instrument to diagnose students’ personal and academic issues and concerns in conjunction with other measures. The norming process includes 1728 students from the different colleges of the University of Mindanao. Further validation is recommended to establish a national norm for the instrument.

Keywords: needs assessment scale, validity, factor analysis, college students

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Authors: Sinuhé Perea Puente

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In several physics systems the whole can be obtained as an exact copy of each of its parts, which facilitates the study of a complex system by looking carefully at its elements, separately. Reducionism offers simplified models which makes the problems easier, but “there’s plenty of room...at the mesoscopic scale”. Here we present a tour for two of its representants: Berry phase and skyrmions, studying some of its basic definitions and properties, and two cases in which both arise together, to finish constraining the scale for our mesoscopic system in the quest of quantum skyrmions, discovering which properties are conserved and which others may be destroyed.

Keywords: condensed mattter, quantum physics, skyrmions, topological defects

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Authors: Mohammed Asiri, Saleh Alsuwayt, Mohammed Bin Mugren, Abdulmalik Almufarrih, Tariq Alotaibi, Saad Almodameg

Abstract:

Background: End-stage renal disease is a major public health concern with high incidence and mortality rate. Most of ESRD patients are on hemodialysis therapy which is a long-term treatment that disturbs patients’ lifestyle. As a result, he will be susceptible to develop psychiatric disorders like anxiety that may direct him to non-compliance on physician instructions and hemodialysis therapy. Although there are studies conducted on psychiatric issues in hemodialysis patients, but few studies focused on the effect of anxiety disorder and the patient’s compliance. Hence, we are interested in determining the prevalence of anxiety disorder among hemodialysis patients in Saudi Arabia, as well as in defining the correlation between anxiety disorder and compliance on physician instructions and hemodialysis therapy. We hypothesize that our study will show a higher prevalence of anxiety in hemodialysis patients than in general population. Also, we expect the anxiety to have a negative impact on their compliance. Methodology: We used a cross-sectional study design carried out at dialysis unit of four major hospitals in Riyadh, KSA. We interviewed 235 End Stage Renal Disease male and female patients who are on hemodialysis. We divided the patients into two categories according to their compliance. we used modified general questionnaire to get their demographic data, then we used a psychometric response scale called visual analog scale (VAS) to assess patient’s compliance to hemodialysis and physician’s instructions. Also, we used the Arabic validated version of the hospital anxiety and depression scale (HAD scale) used mainly for anxiety assessment. Results: The overall response rate was 54%. Respondents included 147 (62.6%) males and 88 (37.4%) females. The prevalence of anxiety among hemodialysis patients is 13.3%. According to visual analog scale, we found that 189 compliant patients and 45 non-compliant patients. For HAD scale, the mean ± standard deviation of the total score for females was (4.44 ± 4.7) and it’s higher than males which was 2.65 ± 3.08 (P-value= 0.002). The mean ± standard deviation of HAD score in the non-compliant group was (5.88  4.88) and it was higher than the compliant group (2.7  3.32) (P-value= 0.004). Among non-complaint group, 33.3% of anxious patients were males and 66.6% were females. There was a negative correlation between HAD score of anxiety and visual analog scale (R= - 0.285). Conclusion: We conclude that there is a high prevalence of anxiety among patients with End Stage Renal Disease that was higher in females with association of non-compliance to physician’s instructions and hemodialysis therapy.

Keywords: anxiety, end-stage renal disease, renal failure, anxiety disorder

Procedia PDF Downloads 274

Authors: A. A. Akharayi, B. E. Anjola

Abstract:

The economic development of a country depends greatly on internally built revenue. Small and Medium-scale Enterprise (SMEs) contributes to the economic buoyancy as it provides employment for the teeming population, encourages job creation by youths who believes in themselves and also by others who have gathered finance enough to invest in growable investment. SMEs is faced with several challenges. The study investigates the role and challenges of SMEs Somolu Local Government Area. Simple random sampling techniques were used to select entrepreneurs (SMEs owners and managers). One hundred and fifty (150) registered SMEs were selected across the LGA data collection with the use of well-structured questionnaire. The data collected were analysed using Statistical Package for Social Science (SPSS) version 21. The result of the analysis indicated that marketing, finance, social facilities and indiscriminate taxes among other high level of fund available significantly (p <0 .05) increase firm capacity while marketing showed a significant (p < 0.05) relationship with profit level.

Keywords: challenge, development, economic, small and medium scale enterprise

Procedia PDF Downloads 239