Search results for: triaxial compression test

Authors: María-Luisa Pinto-Salamanca, Wilson-Javier Pérez-Holguín

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Reconstruction of contact forces is a fundamental technique for analyzing the properties of a touched object and is essential for regulating the grip force in slip control loops. This is based on the processing of the distribution, intensity, and direction of the forces during the capture of the sensors. Currently, efficient hardware alternatives have been used more frequently in different fields of application, allowing the implementation of computationally complex algorithms, as is the case with tactile signal processing. The use of hardware for smart tactile sensing systems is a research area that promises to improve the processing time and portability requirements of applications such as artificial skin and robotics, among others. The literature review shows that hardware implementations are present today in almost all stages of smart tactile detection systems except in the force reconstruction process, a stage in which they have been less applied. This work presents a hardware implementation of a model-driven reported in the literature for the contact force reconstruction of flat and rigid tactile sensor arrays from normal stress data. From the analysis of a software implementation of such a model, this implementation proposes the parallelization of tasks that facilitate the execution of matrix operations and a two-dimensional optimization function to obtain a vector force by each taxel in the array. This work seeks to take advantage of the parallel hardware characteristics of Field Programmable Gate Arrays, FPGAs, and the possibility of applying appropriate techniques for algorithms parallelization using as a guide the rules of generalization, efficiency, and scalability in the tactile decoding process and considering the low latency, low power consumption, and real-time execution as the main parameters of design. The results show a maximum estimation error of 32% in the tangential forces and 22% in the normal forces with respect to the simulation by the Finite Element Modeling (FEM) technique of Hertzian and non-Hertzian contact events, over sensor arrays of 10×10 taxels of different sizes. The hardware implementation was carried out on an MPSoC XCZU9EG-2FFVB1156 platform of Xilinx® that allows the reconstruction of force vectors following a scalable approach, from the information captured by means of tactile sensor arrays composed of up to 48 × 48 taxels that use various transduction technologies. The proposed implementation demonstrates a reduction in estimation time of x / 180 compared to software implementations. Despite the relatively high values of the estimation errors, the information provided by this implementation on the tangential and normal tractions and the triaxial reconstruction of forces allows to adequately reconstruct the tactile properties of the touched object, which are similar to those obtained in the software implementation and in the two FEM simulations taken as reference. Although errors could be reduced, the proposed implementation is useful for decoding contact forces for portable tactile sensing systems, thus helping to expand electronic skin applications in robotic and biomedical contexts.

Keywords: contact forces reconstruction, forces estimation, tactile sensor array, hardware implementation

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Authors: Kayode Fatokun, Nozipho N. Motsa

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Field experiments were carried out during the summer/autumn (first trial) and winter/spring (second trial) seasons of 2019 and 2021 inDlangubo, Ngwelezane, and Mtubatubaareas of KwaZulu-Natal Province of South Africa to study the drought amelioration effects and impact of 2 locally available organic wastes [filter cake (FC) and macadamia husk compost (MHC)] on the productivity, and physiological responses of 4 orange-fleshed sweet potato cultivars (Buregard cv., Impilo, W-119 and 199062.1). The effects of FC and MHC were compared with that of inorganic fertilizer (IF) [2:3:2 (30)], FC+IF, MHC+IF, and control. The soil amendments were applied in the first trials only. Climatic data such as humidity, temperature, and rainfall were taken via remote sensing. The results of the first trial indicated that filter cake and IF significantly performed better than MHC. While the strength of filter cake may be attributable to its rich array of mineral nutrients such as calcium, magnesium, potassium, sodium, zinc, copper, manganese, iron, and phosphorus. The little performance from MHC may be attributable to its water holding capacity. Also, a positive correction occurred between the yield of the test OFSP cultivars and climatic factors such as rainfall, NDVI, and NDWI values. Whereas the inorganic fertilizer did not have any significant effect on the growth and productivity of any of the tested sweet potato cultivars in the second trial; FC, and MHC largely maintained their significant performances. In conclusion, the use of FC is highly recommended in the production of the test orange-fleshed sweet potato cultivars. Also, the study indicated that both FC and MHC may not only supply the needed plant nutrients but has the capacity to reduce the impact of drought on the growth of the test cultivars. These findings are of great value to farmers, especially the resource-poorones.

Keywords: amendments, drought, filter cake, macadamia husk compost, sweet potato

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Authors: Sergio J. Calleja, Adria Roca, José D. Santotoribio

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Pancreatic endocrine diseases include pathologies like insulin resistance (IR), prediabetes, and type 2 diabetes mellitus (DM2). Some of them are highly prevalent in the U.S.—40% of U.S. adults have IR, 38% of U.S. adults have prediabetes, and 12% of U.S. adults have DM2—, as reported by the National Center for Biotechnology Information (NCBI). Building upon this imperative, the objective of the present study was to develop a non-invasive test for the assessment of the patient’s pancreatic endocrine function and to evaluate its accuracy in detecting various pancreatic endocrine diseases, such as IR, prediabetes, and DM2. This approach to a routine blood and urine test is based around serum and urine biomarkers. It is made by the combination of several independent public algorithms, such as the Adult Treatment Panel III (ATP-III), triglycerides and glucose (TyG) index, homeostasis model assessment-insulin resistance (HOMA-IR), HOMA-2, and the quantitative insulin-sensitivity check index (QUICKI). Additionally, it incorporates essential measurements such as the creatinine clearance, estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (ACR), and urinalysis, which are helpful to achieve a full image of the patient’s pancreatic endocrine disease. To evaluate the estimated accuracy of this test, an iterative process was performed by a machine learning (ML) algorithm, with a training set of 9,391 patients. The sensitivity achieved was 97.98% and the specificity was 99.13%. Consequently, the area under the receiver operating characteristic (AUROC) curve, the positive predictive value (PPV), and the negative predictive value (NPV) were 92.48%, 99.12%, and 98.00%, respectively. The algorithm was validated with a randomized controlled trial (RCT) with a target sample size (n) of 314 patients. However, 50 patients were initially excluded from the study, because they had ongoing clinically diagnosed pathologies, symptoms or signs, so the n dropped to 264 patients. Then, 110 patients were excluded because they didn’t show up at the clinical facility for any of the follow-up visits—this is a critical point to improve for the upcoming RCT, since the cost of each patient is very high and for this RCT almost a third of the patients already tested were lost—, so the new n consisted of 154 patients. After that, 2 patients were excluded, because some of their laboratory parameters and/or clinical information were wrong or incorrect. Thus, a final n of 152 patients was achieved. In this validation set, the results obtained were: 100.00% sensitivity, 100.00% specificity, 100.00% AUROC, 100.00% PPV, and 100.00% NPV. These results suggest that this approach to a routine blood and urine test holds promise in providing timely and accurate diagnoses of pancreatic endocrine diseases, particularly among individuals aged 40 and above. Given the current epidemiological state of these type of diseases, these findings underscore the significance of early detection. Furthermore, they advocate for further exploration, prompting the intention to conduct a clinical trial involving 26,000 participants (from March 2025 to December 2026).

Keywords: algorithm, diabetes, laboratory medicine, non-invasive

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Authors: Muhammad Zaheer Babar, Amer Kashif, Muhammad Rizwan Javed

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Nowadays distributed generation integration is best way to overcome the increasing load demand. Optimal allocation of distributed generation plays a vital role in reducing system losses and improves voltage profile. In this paper, a Meta heuristic technique is proposed for allocation of DG in order to reduce power losses and improve voltage profile. The proposed technique is based on Multi Objective Particle Swarm optimization. Fewer control parameters are needed in this algorithm. Modification is made in search space of PSO. The effectiveness of proposed technique is tested on IEEE 33 bus test system. Single DG as well as multiple DG scenario is adopted for proposed method. Proposed method is more effective as compared to other Meta heuristic techniques and gives better results regarding system losses and voltage profile.

Keywords: Distributed generation (DG), Multi Objective Particle Swarm Optimization (MOPSO), particle swarm optimization (PSO), IEEE standard Test System

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Authors: E. Olmos-Raya, A. Cascales Martínez, N. Minto de Sousa, M. Alcañiz Raya

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The late detection and subjectivity of the assessment of Autism Spectrum Disorder (ASD) imposed a difficulty for the children’s clinical and familiar environment. The results showed in this paper, are part of a research project about the assessment and training of social skills in children with ASD, whose overall goal is the use of virtual environments together with physiological measures in order to find a new model of objective ASD assessment based on implicit brain processes measures. In particular, this work tries to contribute by studying the differences and changes in the Skin Conductance Response (SCR) and Eye Tracking (ET) between a typical development group (TD group) and an ASD group (ASD group) after several combined stimuli using a low cost Immersive Virtual Environment (IVE). Subjects were exposed to a virtual environment that showed natural scenes that stimulated visual, auditory and olfactory perceptual system. By exposing them to the IVE, subjects showed natural behaviors while measuring SCR and ET. This study compared measures of subjects diagnosed with ASD (N = 18) with a control group of subjects with typical development (N=10) when exposed to three different conditions: only visual (V), visual and auditory (VA) and visual, auditory and olfactory (VAO) stimulation. Correlations between SCR and ET measures were also correlated with the Autism Diagnostic Observation Schedule (ADOS) test. SCR measures showed significant differences among the experimental condition between groups. The ASD group presented higher level of SCR while we did not find significant differences between groups regarding DF. We found high significant correlations among all the experimental conditions in SCR measures and the subscale of ADOS test of imagination and symbolic thinking. Regarding the correlation between ET measures and ADOS test, the results showed significant relationship between VA condition and communication scores.

Keywords: autism, electrodermal activity, eye tracking, immersive virtual environment, virtual reality

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Authors: J. R. Bhalla, Gautam, Gurcharan Singh, Sanjeev Naval

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Mathematics is everywhere behind the every things on the earth as well as in the universe. Predynastic Egyptians of the 5th millennium BC pictorially represented geometric designs. Now a day’s we can made and apply an equation on a complex geometry through applied mathematics. Here we work and focus on to create a formula which apply in the field of civil engineering in new concrete technology. In this paper our target is to make a formula which is applied on “BAUT” Metal Aggregate. In this paper our approach is to make formulation and equation on special “BAUT” Metal Aggregate by Applied Mathematical Study Case 1. BASIC PHYSICAL FORMULATION 2. ADVANCE EQUATION which shows the mechanical performance of special metal aggregates for concrete technology. In case 1. Basic physical formulation shows the surface area and volume manually and in case 2. Advance equation shows the mechanical performance has been discussed, the metal aggregates which had outstandingly qualities to resist shear, tension and compression forces. In this paper coarse metal aggregates is 20 mm which used for making high performance concrete (H.P.C).

Keywords: applied mathematical study case, special metal aggregates, concrete technology, basic physical formulation, advance equation

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Authors: Christian J. Kennett, Mark A. Baldwin

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As several companies are working towards returning American astronauts back to space on US-made spacecraft, NASA developed a human flight certification-by-test and analysis approach due to the cost-prohibitive nature of extensive testing. This process relies heavily on the quality of analytical models to accurately predict crew injury potential specific to each spacecraft and under dynamic environments not tested. As the prime contractor on the Orion spacecraft, Lockheed Martin was tasked with quantifying the correlation of analytical anthropometric test devices (ATDs), also known as crash test dummies, against test measurements under representative impact conditions. Multiple dynamic impact sled tests were conducted to characterize Hybrid III 5th ATD lumbar, head, and neck responses with and without a modified shuttle-era advanced crew escape suit (ACES) under simulated Orion landing and abort conditions. Each ATD was restrained via a 5-point harness in a mockup Orion seat fixed to a dynamic impact sled at the Wright Patterson Air Force Base (WPAFB) Biodynamics Laboratory in the horizontal impact accelerator (HIA). ATDs were subject to multiple impact magnitudes, half-sine pulse rise times, and XZ - ‘eyeballs out/down’ or Z-axis ‘eyeballs down’ orientations for landing or an X-axis ‘eyeballs in’ orientation for abort. Several helmet constraint devices were evaluated during suited testing. Unique finite element models (FEMs) were developed of the unsuited and suited sled test configurations using an analytical 5th ATD model developed by LSTC (Livermore, CA) and deformable representations of the seat, suit, helmet constraint countermeasures, and body restraints. Explicit FE analyses were conducted using the non-linear solver LS-DYNA. Head linear and rotational acceleration, head rotational velocity, upper neck force and moment, and lumbar force time histories were compared between test and analysis using the enhanced error assessment of response time histories (EEARTH) composite score index. The EEARTH rating paired with the correlation and analysis (CORA) corridor rating provided a composite ISO score that was used to asses model correlation accuracy. NASA occupant protection subject matter experts established an ISO score of 0.5 or greater as the minimum expectation for correlating analytical and experimental ATD responses. Unsuited 5th ATD head X, Z, and resultant linear accelerations, head Y rotational accelerations and velocities, neck X and Z forces, and lumbar Z forces all showed consistent ISO scores above 0.5 in the XZ impact orientation, regardless of peak g-level or rise time. Upper neck Y moments were near or above the 0.5 score for most of the XZ cases. Similar trends were found in the XZ and Z-axis suited tests despite the addition of several different countermeasures for restraining the helmet. For the X-axis ‘eyeballs in’ loading direction, only resultant head linear acceleration and lumbar Z-axis force produced ISO scores above 0.5 whether unsuited or suited. The analytical LSTC 5th ATD model showed good correlation across multiple head, neck, and lumbar responses in both the unsuited and suited configurations when loaded in the XZ ‘eyeballs out/down’ direction. Upper neck moments were consistently the most difficult to predict, regardless of impact direction or test configuration.

Keywords: impact biomechanics, manned spaceflight, model correlation, multi-axial loading

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Authors: Qian Mao, Xiaozan Wang, Jiarong Zhong, Xiaolin Zou

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Introduction: As a result of the decline of students' physical health level and the increase of study pressure, students’ academic performance is not so good. Objective: This study aims to verify whether the Brain-Break intervention in the fourth-grade classroom of primary school can improve students' physical health and academic performance. Methods: According to the principle of no difference in pre-test data, students from two classes of grade four in Fuhai Road Primary School, Fushan district, Yantai city, Shandong province, were selected as experimental subjects, including 50 students in the experimental class (25 males and 25 females) and 50 students in the control class (24 males and 26 females). The content of the experiment was that the students were asked to perform a 4-minute Brain-Berak program designed by the researcher in the second class in the morning and the afternoon, and the intervention lasted for 12 weeks. In addition, the lung capacity, 50-meter run, sitting body forward bend, one-minute jumping rope and one-minute sit-ups stipulated in the national standards for physical fitness of students (revised in 2014) were selected as the indicators of physical health. The scores of Chinese, Mathematics, and English in the unified academic test of the municipal education bureau were selected as the indicators of academic performance. The independent-sample t-test was used to compare and analyze the data of each index between the two classes. The paired-sample t-test was used to compare and analyze the data of each index in the two classes. This paper presents only results with significant differences. Results: in terms of physical health, lung capacity (P=0.002, T= -2.254), one-minute rope skipping (P=0.000, T=3.043), and one-minute sit-ups (P=0.045, T=6.153) were significantly different between the experimental class and the control class. In terms of academic performance, there is a significant difference between the Chinese performance of the experimental class and the control class (P=0.009, T=4.833). Conclusion: Adding Brain-Berak intervention in the classroom can effectively improve the cardiorespiratory endurance (lung capacity), coordination (jumping rope), and abdominal strength (sit-ups) of fourth-grade students. At the same time, it can also effectively improve their Chinese performance. Therefore, it is suggested to promote micro-sports in the classroom of primary schools throughout the country so as to help students improve their physical health and academic performance.

Keywords: academic performance, brain break, fourth grade, physical health

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Authors: Taejin Kim, Heonwoo Lee, Jong-Ho Kim, Dongchul Lee

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Recently, there have been various high-rise building projects which reflect unique inspiration from architects to their feature. And it is frequently found that some of these buildings have diagrid structural system. Diagrid system provides engineers many options for structural plan, since it has triangular module so it can form a number of complex shapes. Unlike braced frame systems, diagonal members in diagrid system resist gravity and horizontal loads simultaneously. Correspondingly, diagrid members take roles of both beams and columns, and it is expected that their ductile capacity may depend on the amount of gravity loads. However, not enough studies have been made for this issue so far, which means that there is demand of examination on the seismic behavior of diagrid members under large gravity loads. Therefore, in this study, the ductile capacity of diagrid members was evaluated through analytical and experimental method. Several cases that have different vertical load condition were set up for both approaches to consider the effect of initial compression force due to gravity load. Regarding the result, it was found that buckling in a diagonal member occurs at smaller drift angle when larger gravity load acts on the specimen, which also reduces the amount of energy dissipation. It means that axial stress in a diagonal member reaches critical buckling force early due to the combined axial force from not only horizontal load but also gravity load.

Keywords: buckling, diagrid, ductility, seismic performance

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Authors: Rizwan Fazal

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This study investigates the behavior of external sector of Pakistan economy and its impact on economic growth, using quarterly data for the period 1990:01-2010:04. External sector indices used in this study are financial integration, net foreign assets and trade integration. Augmented Ducky fuller confirms that all variables of external sector are non-stationary at level, but at first difference it becomes stationary. The co-integration test suggests one co-integrating variables in the study. The analysis is based on Vector Auto Regression model followed by Vector Error Correction Model. The empirical findings show that financial integration play important role in increasing economic growth in Pakistan economy while trade integration has negative effect on economic growth of Pakistan in the long run. However, the short run confirms that output lag accounts for error correction. The estimated CUSUM and CUSUMQ stability test provide information that the period of the study equation remains stable.

Keywords: financial integration, trade integration, net foreign assets, gross domestic product

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Authors: Yu-Ju Tsai, Ching-Chun Wang, Wen-Tzu Tang, Huei-Ming Chai

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A pronated foot is frequently associated with a hypermobile first ray, then developing further severe foot problems. Low-Dye taping with athletic tape has been widely used to restrict excessive first ray motion and re-build height of the medial longitudinal arch in general population with pronated foot. It is not the case, however, for sprinters since they feel too much restriction of foot motions. Currently, the kinesio tape, more elastic than the athletic tape, has been widely used to re-adjust joint positions. It was interesting whether modified low-Dye taping using kinesio tape was beneficial for altering first ray mobility and still giving enough arch support. The purpose of this study was to investigate the effect of modified low-Dye taping on first ray mobility test and 60-m sprint time for sprinters with pronated foot. The significance of this study provides new insight into a treatment alternative of modified low-Dye taping for sprinter with pronated foot. Ten young male sprinters, aged 20.8±1.6 years, with pronated foot were recruited for this study. The pronated foot was defined as the foot that the navicular drop test was greater than 1.0 cm. Three optic shutters were placed at the start, 30-m, and 60-m sites to record sprint time. All participants were asked to complete 3 trials of the 60-m dash with both taping and non-taping conditions in a random order. The low-Dye taping was applied using the method postulated by Ralph Dye in 1939 except the kinesio tape was used instead. All outcome variables were recorded for taping and non-taping conditions. Paired t-tests were used to analyze all outcome variables between 2 conditions. Although there were no statistically significant differences in dorsal and plantar mobility between taping and non-taping conditions, a statistical significance was found in a total range of motion (dorsiflexion plus plantarflexion angle) of the first ray when a modified low-Dye taping was applied (p < 0.05). Time to complete 60-m sprint was significantly increased with low-Dye taping (p < 0.05) while no significance was found for time to 30-m. it indicated that modified low-Dye taping changed maximum sprint speed of 60-m dash. Conclusively, modified low-Dye taping was capable of increasing first ray mobility and further altered maximum sprint speed.

Keywords: first ray mobility, kinesio taping, pronated foot, sprint time

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Authors: K. Raza, S. Gul, M. Ali

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Concrete is a fundamental building material, extensively utilized by the construction industry. Problems related to the strength of concrete is an immense issue for the sustainability of concrete structures. Concrete mostly loses its strength due to the cracks produced in it by shrinkage or hydration process. This study aims to enhance the strength and service life of the concrete structures by incorporating bio-based admixture in the concrete. By the injection of bio-based admixture (BBA) in concrete, it will self-heal the cracks by producing calcium carbonate. Minimization of cracks will compact the microstructure of the concrete, due to which strength will increase. For this study, Bacillus subtilis will be used as a bio-based admixture (BBA) in concrete. Calcium lactate up to 1.5% will be used as the food source for the Bacillus subtilis in concrete. Two formulations containing 0 and 5% of Bacillus subtilis by weight of cement, will be used for the casting of concrete specimens. Direct mixing method will be adopted for the usage of bio-based admixture in concrete. Compressive strength test will be carried out after 28 days of curing. Scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) will be performed for the examination of micro-structure of concrete. Results will be drawn by comparing the test results of 0 and 5% the formulations. It will be recommended to use to bio-based admixture (BBA) in concrete for columns because of the satisfactory increase in the compressive strength of concrete.

Keywords: bio-based admixture, Bacillus subtilis, calcium lactate, compressive strength

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Authors: Surachart Koyadun

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Currently, Plasmodium knowlesi malaria has spread to almost all countries in Southeast Asia. This research aimed to 1) describe the epidemiology of Plasmodium knowlesi malaria, 2) examine the clinical symptoms of P. knowlesi malaria patients 3) analyze the ecology, animal reservoir and entomology of P. knowlesi malaria. 4) summarize the diagnosis, blood parasites, and treatment of P. knowlesi malaria. The study design was a case report combined with retrospective descriptive survey research. A total of 34 study subjects were patients with a confirmed diagnosis of P. knowlesi malaria who received treatment at hospitals and vector-borne disease control units in Songkhla Province during 2021 – 2022. The results of the epidemiological study unveiled the majority of the samples were male, had a history of staying overnight in the forest before becoming sick, the source of the infection was in the forest, and the season during which they were sick was mostly summer. The average length of time from the onset of illness until receiving a blood test was 3.8 days. The average length of hospital stay was 4 days. Patients were treated with Chloroquine Phosphate, Primaquine, Artesunate, Quinine, and Dihydroartemisinin-piperaquine (40 mg DHA-320 mg PPQ). One death was seen in 34 P. knowlesi malaria patients. All remaining patients recovered and responded to treatment. All symptoms improved after drug administration. No treatment failures were found. Analyses of ecological, zoonotic and entomological data revealed an association between infected patients and forested, monkey-hosted and mosquito-transmitted areas. The recommendation from this study was that the Polymerase Chain Reaction (PCR) method should be used in conjunction with the Thick/Thin Film test and blood parasite test (Parasitaemia) for the specificity of the infection, accuracy of diagnosis, leading to treatment of disease in a timely manner and be effective in disease control.

Keywords: human malaria, Plasmodium knowlesi, zoonotic disease, diagnosis and treatment, epidemiology, ecology

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Authors: Wilawan Kanhachon, Yodchai Boonprakob, Uraiwon Chatchawan, Junichiro Yamauchi

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Introduction: Paslop is a traditional dance from Laos, which is popular in Laos and northeastern of Thailand. This unique type of Paslop dancing is to control body movement with the song. While dancing to the beat, dancers should contract their abdomen and back muscle all the time. Paslop may be a good alternative to improve strengthening, balance and flexibility. Objective: To investigate the effects of Paslop dance exercise on core strength, balance, and flexibility. Methods: Seven healthy participants (age, 20.57±1.13 yrs; height, 162.29±6.16 cm; body mass, 58.14±7.03 kg; mean± S.D.) were volunteered to perform the 45-minute Paslop dance exercise in three times a week for 8 weeks. Before, during and after the exercise period, core strength, balance and flexibility were measured with the pressure biofeedback unit (PBU), one-leg stance test (OLST), and sit and reach test (SAR), respectively. Result: PBU score for core strength increased from 2.12 mmHg in baseline to 6.34 mmHg at the 4th week and 10.10 mmHg at the 8th week after the Paslop dance training, while OLST and SAR did not change. Conclusion: The study demonstrates that 8-week Paslop dancing exercise can improve the core strength.

Keywords: balance, core strength, flexibility, Paslop

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Authors: Reinhard Hermawan Lasut, Henki Wibowo Ashadi

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The use of materials in Indonesia's construction sector requires engineers and practitioners to develop efficient construction technology, one of the materials used in cold-formed steel. Generally, the use of cold-formed steel is used in the construction of roof trusses found in houses or factories. The failure of the roof truss structure causes errors in the calculation analysis in the form of cross-sectional dimensions or frame configuration. The roof truss structure, vertical distance effect to the span length at the edge of the frame carries the compressive load. If the span is too long, local buckling will occur which causes problems in the frame strength. The model analysis uses various shapes of roof trusses, span lengths and angles with analysis of the structural stiffness matrix method. Model trusses with one-fifth shortened span and one-sixth shortened span also The trusses model is reviewed with increasing angles. It can be concluded that the trusses model by shortening the span in the compression area can reduce deflection and the model by increasing the angle does not get good results because the higher the roof, the heavier the load carried by the roof so that the force is not channeled properly. The shape of the truss must be calculated correctly so the truss is able to withstand the working load so that there is no structural failure.

Keywords: cold-formed, trusses, deflection, stiffness matrix method

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Authors: Çiğdem Sezer, Aksem Aksoy, Leyla Vatansever

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This study has been done for the purpose of evaluation of public health and identifying of enterotoxigenic Staphyloccocus aureus in kitchen of catering. In the kitchen of catering, samples have been taken by swabs from surface of equipments which are in the salad section, meat section and bakery section. Samples have been investigated with classical cultural methods in terms of Staphyloccocus aureus. Therefore, as a 10x10 cm area was identified (salad, cutting and chopping surfaces, knives, meat grinder, meat chopping surface) samples have been taken with sterile swabs with helping FTS from this area. In total, 50 samples were obtained. In aseptic conditions, Baird-Parker agar (with egg yolk tellurite) surface was seeded with swabs. After 24-48 hours of incubation at 37°C, the black colonies with 1-1.5 mm diameter and which are surrounded by a zone indicating lecithinase activity were identified as S. aureus after applying Gram staining, catalase, coagulase, glucose and mannitol fermentation and termonuclease tests. Genotypic characterization (Staphylococcus genus and S.aureus species spesific) of isolates was performed by PCR. The ELISA test was applied to the isolates for the identification of staphylococcal enterotoxins (SET) A, B, C, D, E in bacterial cultures. Measurements were taken at 450 nm in an ELISA reader using an Ridascreen-Total set ELISA test kit (r-biopharm R4105-Enterotoxin A, B, C, D, E). The results were calculated according to the manufacturer’s instructions. A total of 50 samples of 97 S. aureus was isolated. This number has been identified as 60 with PCR analysis. According to ELISA test, only 1 of 60 isolates were found to be enterotoxigenic. Enterotoxigenic strains were identified from the surface of salad chopping and cutting. In the kitchen of catering, S. aureus identification indicates a significant source of contamination. Especially, in raw consumed salad preparation phase of contamination is very important. This food can be a potential source of food-borne poisoning their terms, and they pose a significant risk to consumers have been identified.

Keywords: Staphylococcus aureus, enterotoxin, catering, kitchen, health

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Authors: Chung Danbi, Linton Oliver, Whang Yoon-Jae

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Supermodularity, or complementarity, is a popular concept in economics which can characterize many objective functions such as utility, social welfare, and production functions. Further, supermodular dominance captures a preference for greater interdependence among inputs of those functions, and it can be applied to examine which input set would produce higher expected utility, social welfare, or production. Therefore, we propose and justify a consistent testing for a useful implication of supermodular dominance. We also conduct Monte Carlo simulations to explore the finite sample performance of our test, with critical values obtained from the recentered bootstrap method, with and without the selective recentering, and the subsampling method. Under various parameter settings, we confirmed that our test has reasonably good size and power performance. Finally, we apply our test to compare the geographic and distant knowledge spillover in terms of their effects on social welfare using the National Bureau of Economic Research (NBER) patent data. We expect localized citing to supermodularly dominate distant citing if the geographic knowledge spillover engenders greater social welfare than distant knowledge spillover. Taking subgroups based on firm and patent characteristics, we found that there is industry-wise and patent subclass-wise difference in the pattern of supermodular dominance between localized and distant citing. We also compare the results from analyzing different time periods to see if the development of Internet and communication technology has changed the pattern of the dominance. In addition, to appropriately deal with the sparse nature of the data, we apply high-dimensional methods to efficiently select relevant data.

Keywords: supermodularity, supermodular dominance, stochastic dominance, Monte Carlo simulation, bootstrap, subsampling

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Authors: Zachary Pan

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Our general mission is to solve the problem of classifying images into different body part types and deciding if each of them is healthy or not. However, for now, we will determine healthiness for only one-sixth of the body parts, specifically the chest. We will detect pneumonia in X-ray scans of those chest images. With this type of AI, doctors can use it as a second opinion when they are taking CT or X-ray scans of their patients. Another ad-vantage of using this machine learning classifier is that it has no human weaknesses like fatigue. The overall ap-proach to this problem is to split the problem into two parts: first, classify the image, then determine if it is healthy. In order to classify the image into a specific body part class, the body parts dataset must be split into test and training sets. We can then use many models, like neural networks or logistic regression models, and fit them using the training set. Now, using the test set, we can obtain a realistic accuracy the models will have on images in the real world since these testing images have never been seen by the models before. In order to increase this testing accuracy, we can also apply many complex algorithms to the models, like multiplicative weight update. For the second part of the problem, to determine if the body part is healthy, we can have another dataset consisting of healthy and non-healthy images of the specific body part and once again split that into the test and training sets. We then use another neural network to train on those training set images and use the testing set to figure out its accuracy. We will do this process only for the chest images. A major conclusion reached is that convolutional neural networks are the most reliable and accurate at image classification. In classifying the images, the logistic regression model, the neural network, neural networks with multiplicative weight update, neural networks with the black box algorithm, and the convolutional neural network achieved 96.83 percent accuracy, 97.33 percent accuracy, 97.83 percent accuracy, 96.67 percent accuracy, and 98.83 percent accuracy, respectively. On the other hand, the overall accuracy of the model that de-termines if the images are healthy or not is around 78.37 percent accuracy.

Keywords: body part, healthcare, machine learning, neural networks

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Authors: Khobaib Khobaib, Alexander Mikkelsen, Zbigniew Rozynek

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Electric fields have proven useful for inducing droplet deformation and to structure particles adsorbed at droplet interfaces. In this experimental research, direct current electric fields were applied to deform particle-covered droplets made out of silicone oil and immersed in castor oil. The viscosity of the drop and surrounding fluid were changed by external heating. We designed an experimental system in such a way that electric field-induced electrohydrodynamic (EHD) flows were asymmetric and only present on one side of the drop, i.e., the droplet adjoined a washer and adhered to one of the electrodes constituting the sample cell. The study investigated the influence of viscosity on the steady-state deformation magnitude of particle-laden droplets, droplet compression, and relaxation, as well as particle arrangements at drop interfaces. Initially, before the application of an electric field, we changed the viscosity of the fluids by heating the sample cell at different temperatures. The viscosity of the fluids was varied by changing the temperature of the fluids from 25 to 50°C. Under the application of a uniform electric field of strength 290 Vmm⁻¹, electric stress was induced at the drop interface, yielding drop deformation. In our study, we found that by lowering the fluid viscosity, the velocity of the EHD flows was increased, which also increases the deformation of the drop.

Keywords: drop deformation and relaxation, electric field, electrohydrodynamic flow, particle assembly, viscosity

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Authors: Yuzman Yusoff, Siti Noor Harun, Noor Shelida Salleh, Tan Kong Yew

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This paper presents the design and characterization of analog readout interface circuits for ion sensitive field effect transistor (ISFET) and ion selective electrode (ISE) based sensor. These interface circuits are implemented using MIMOS’s 0.35um CMOS technology and experimentally characterized under 24-leads QFN package. The characterization evaluates the circuit’s functionality, output sensitivity and output linearity. Commercial sensors for both ISFET and ISE are employed together with glass reference electrode during testing. The test result shows that the designed interface circuits manage to readout signals produced by both sensors with measured sensitivity of ISFET and ISE sensor are 54mV/pH and 62mV/decade, respectively. The characterized output linearity for both circuits achieves above 0.999 rsquare. The readout also has demonstrated reliable operation by passing all qualifications in reliability test plan.

Keywords: readout interface circuit (ROIC), analog interface circuit, ion sensitive field effect transistor (ISFET), ion selective electrode (ISE), ion sensor electronics

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Authors: Ka Ho Yau, Jan Frederick Engels, Kwok Kei Lai, Reinhard Renneberg

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Lateral flow test is a prevalent technology in various sectors such as food, pharmacology and biomedical sciences. Colloidal gold (CG) is widely used as the signalling molecule because of the ease of synthesis, bimolecular conjugation and its red colour due to intrinsic SPRE. However, the production of colloidal gold is costly and requires vigorous conditions. The stability of colloidal gold are easily affected by environmental factors such as pH, high salt content etc. Silica nanoparticles are well known for its ease of production and stability over a wide range of solvents. Using reverse micro-emulsion (w/o), silica nanoparticles with different sizes can be produced precisely by controlling the amount of water. By incorporating different water-soluble dyes, a rainbow colour of the silica nanoparticles could be produced. Conjugation with biomolecules such as antibodies can be achieved after surface modification of the silica nanoparticles with organosilane. The optimum amount of the antibodies to be labelled was determined by Bradford Assay. In this work, we have demonstrated the ability of the dye-doped silica nanoparticles as a signalling molecule in lateral flow test, which showed a semi-quantitative measurement of the analyte. The image was further analysed for the LOD=10 ng of the analyte. The working range and the linear range of the test were from 0 to 2.15μg/mL and from 0 to 1.07 μg/mL (R2=0.988) respectively. The performance of the tests was comparable to those using colloidal gold with the advantages of lower cost, enhanced stability and having a wide spectrum of colours. The positives lines can be imaged by naked eye or by using a mobile phone camera for a better quantification. Further research has been carried out in multicolour detection of different biomarkers simultaneously. The preliminary results were promising as there was little cross-reactivity being observed for an optimized system. This approach provides a platform for multicolour detection for a set of biomarkers that enhances the accuracy of diseases diagnostics.

Keywords: colorimetric detection, immunosensor, paper-based biosensor, silica

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Authors: Shanika Y. Koreshi

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Sri Lanka housed the lingerie product development and manufacturing subsidiary to renowned brands such as La Senza, Marks & Spencer, H&M, Etam, Lane Bryant, and George. Over the last few years, they have produced local brands such as Amante to cater to the local and regional customers. Past research has identified factors such as quality, price, and design to be vital when marketing lingerie to consumers. However, there has been minimum research that looks into the ethnically targeted market and skin colour within the Asian population. Therefore, the main aim of the research was to identify whether consumer preference for lingerie is influenced by the skin tone of the model wearing it. Moreover, the secondary aim was to investigate if the consumer preference for lingerie is influenced by the consumer’s ethnic identification with the skin tone of the model. An experimental design was used to explore the above aims. The participants constituted of 66 females residing in the western province of Sri Lanka and were gathered via convenience sampling. Six computerized images of a real model were used in the study, and her skin tone was digitally manipulated to express three different skin tones (light, tan and dark). Consumer preferences were measured through a ranking order scale that was constructed via a focus group discussion and ethnic identity was measured by the Multigroup Ethnic Identity Measure-Revised. Wilcoxon signed-rank test, Friedman test, and chi square test of independence were carried out using SPSS version 20. The results indicated that majority of the consumers ethnically identified and preferred the tan skin over the light and dark skin tones. The findings support the existing literature that states there is a preference among consumers when models have a medium skin tone over a lighter skin tone. The preference for a tan skin tone in a model is consistent with the ethnic identification of the Sri Lankan sample. The study implies that lingerie brands should consider the model's skin tones when marketing the brand to different ethnic backgrounds.

Keywords: consumer preference, ethnic identification, lingerie, skin tone

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Authors: I. O. Oladele, J. A. Omotoyinbo, A. M. Okoro, A. G. Okikiola, J. L. Olajide

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This work was carried out to investigate comparatively the effects of modified and unmodified cow bone particles on the mechanical properties of polyester matrix composites in order to investigate the suitability of the materials as biomaterial. Cow bones were procured from an abattoir, sun dried for 4 weeks and crushed. The crushed bones were divided into two, where one part was turned to ash while the other part was pulverized with laboratory ball mill before the two grades were sieved using 75 µm sieve size. Bone ash and bone particle reinforced tensile and flexural composite samples were developed from pre-determined proportions of 2, 4, 6, and 8 %. The samples after curing were stripped from the moulds and were allowed to further cure for 3 weeks before tensile and flexural tests were performed on them. The tensile test result showed that, 8 wt % bone particle reinforced polyester composites has higher tensile properties except for modulus of elasticity where 8 wt % bone ash particle reinforced composites has higher value while for flexural test, bone ash particle reinforced composites demonstrate the best flexural properties. The results show that these materials are structurally compatible.

Keywords: biomedical, composites, cow bone, mechanical properties, polyester, reinforcement

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Authors: Alvaro Jose Cordova, Hsuan Teh Hu

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The use of concrete masonry constructions in developing countries has become very frequent, especially for domestic purpose. Most of them with asymmetric wall configurations in plan resulting in significant torsional actions when subjected to seismic loads. The study consisted on the finding of a material model for hollow unreinforced concrete masonry and a validation with experimental data found in literature. Numerical simulations were performed to 20 buildings with variations in wall distributions and heights. Results were analyzed by inspection and with a non-linear static method. The findings revealed that eccentricities as well as structure rigidities have a strong influence on the overall response of concrete masonry buildings. In addition, slab rotations depicted more accurate information about the torsional behavior than maximum versus average displacement ratios. The failure modes in low buildings were characterized by high tensile strains in the first floor. Whereas in tall buildings these strains were lowered significantly by higher compression stresses due to a higher self-weight. These tall buildings developed multiple plastic hinges along the height. Finally, the non-linear static analysis exposed a brittle response for all masonry assemblies. This type of behavior is undesired in any construction and the need for a material model for reinforced masonry is pointed out.

Keywords: concrete damaged plasticity, concrete masonry, macro-modeling, nonlinear static analysis, torsional capacity

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Authors: YongSeok Choi, HwaYoung Seo, InSu Whang, GeogKee Park

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Frankliniella. occidentalis is major pest in chrysanthemum in worldwide. The density of F. occidentalis increased continuously in spite of the periodical chemical control after planting in this study. F. occidentalis began to increase mid-May. The numbers of F. occidentalis collected on a tray with wet paper by heating the flowers of pink, white, and yellow Chrysanthemum standard mums were 18.4, 56.6, and 52.6 in the flowering season. Also, the numbers were 15.2, 45.8, and 41.6 in bud season, but in the case of the leaves, the numbers were 2, 8.8 and 3.4. In the Y-tube olfactometer test, the frequency of F. occidentalis’ visits to one side arm of the Y-tube olfactometer was higher in the odor cue of the white flower than of the yellow, red, and violet flowers, but the frequency was higher in the odor cue of the violet and red flowers than of the yellow without white. In the case of the four-choice olfactometer test, in the same visual cues as the odor cues of the pot mum flowers, the frequency of F. occidentalis was higher in the yellow flower than in the other flowers (white, red, and violet) in all the observation times (10, 15, and 20 minutes).

Keywords: Frankliniella occidentalis, Chrysanthemum, trap plant, control effect

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Authors: Saima Sharif Nilla, Mahmudur Rahman Khan, Anisur Rahman Khan, Ghulam Mustafa1

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The microbial quality of Indian white shrimp (Peneaus indicus) from Bagerhat, Khulna and Satkhira of southwest Bangladesh was assessed where the parameters varied with different sources and the quality was found to be poor for Satkhira shrimp samples. Shrimp samples in fresh condition were collected to perform the microbial assessment and 10 pathogenic isolates for antibiotic sensitivity test to 12 antibiotics. The results show that total bacterial count of all the samples were beyond the acceptable limit 105 cfu/g. In case of total coliform and E. coli density, no substantial difference (p<0.5) was found between the different shrimp samples from different districts and also high quantity of TC exceeding the limit (>102 cfu/g) proves the poor quality of shrimp. The FC abundance found in shrimps of Bagerhat and Satkhira was similar and significantly higher (p<0.5) than that of Khulna samples. No significant difference (p<0.5) was found among the high density of Salmonella-Shigella, Vibrio spp., and Staphylococcus spp. of the shrimp samples from the source places. In case of antibiotic sensitivity patterns, all of them were resistant to ampicillin, Penicillin and sensitive to kanamycin. Most of the isolates were frequently sensitive to ciprofloxacin and streptomycin in the sensitivity test. In case of nutritional composition, no significant difference (t-test, p<0.05) was found among protein, lipid, moisture and ash contents of shrimp samples. The findings prove that shrimp under this study was more or less contaminated and samples from Satkhira were highly privileged with food borne pathogens which confirmed the unhygienic condition of the shrimp farms as well as the presence of antibiotic resistance bacteria in shrimp fish supposed to threat food safety and deteriorate the export quality.

Keywords: food borne pathogens, satkhira, penaeus indicus, antibiotic sensitivity, southwest Bangladesh, food safety

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Authors: Ákos Wolf, Richard P. Ray

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Due to the introduction of Eurocode 8, the structural design for seismic and dynamic effects has become more significant in Hungary. This has emphasized the need for more effort to describe the behavior of structures under these conditions. Soil conditions have a significant effect on the response of structures by modifying the stiffness and damping of the soil-structural system and by modifying the seismic action as it reaches the ground surface. Shear modulus (G) and shear wave velocity (v_s), which are often measured in the field, are the fundamental dynamic soil properties for foundation vibration problems, liquefaction potential and earthquake site response analysis. There are several laboratory and in-situ measurement techniques to evaluate dynamic soil properties, but unfortunately, they are often too expensive for general design practice. However, a significant number of correlations have been proposed to determine shear wave velocity or shear modulus from Cone Penetration Tests (CPT), which are used more and more in geotechnical design practice in Hungary. This allows the designer to analyze and compare CPT and seismic test result in order to select the best correlation equations for Hungarian soils and to improve the recommendations for the Hungarian geologic conditions. Based on a literature review, as well as research experience in Hungary, the influence of various parameters on the accuracy of results will be shown. This study can serve as a basis for selecting and modifying correlation equations for Hungarian soils. Test data are taken from seven locations in Hungary with similar geologic conditions. The shear wave velocity values were measured by seismic CPT. Several factors are analyzed including soil type, behavior index, measurement depth, geologic age etc. for their effect on the accuracy of predictions. The final results show an improved prediction method for Hungarian soils

Keywords: CPT correlation, dynamic soil properties, seismic CPT, shear wave velocity

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Authors: Marzena Tokarewicz, Malgorzata Gradzka-Dahlke

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High-entropy alloys (HEAs) have gained significant attention due to their great potential as functional and structural materials. HEAs have very good mechanical properties (in particular, alloys based on CoCrNi). They also show the ability to maintain their strength at high temperatures, which is extremely important in some applications. AlCoCrFeNi alloy is one of the most studied high-entropy alloys. Scientists often study the effect of changing the aluminum content in this alloy because it causes significant changes in phase presence and microstructure and consequently affects its hardness, ductility, and other properties. Research conducted by the authors also investigates the effect of aluminium content in AlₓCoCrFeNi alloy on its microstructure and mechanical properties. AlₓCoCrFeNi alloys were prepared by vacuum induction melting. The obtained samples were examined for chemical composition, microstructure, and microhardness. The three-point bending method was carried out to determine the bending strength, bending modulus, and conventional bending yield strength. The obtained results confirm the influence of aluminum content on the properties of AlₓCoCrFeNi alloy. Most studies on AlₓCoCrFeNi alloy focus on the determination of mechanical properties in compression or tension, much less in bending. The achieved results provide valuable information on the bending properties of AlₓCoCrFeNi alloy and lead to interesting conclusions.

Keywords: bending properties, high-entropy alloys, induction melting, microstructure

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Authors: Renu Kumari, Jyotsna Dutta Majumdar

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In the present study, composite coating consisting of hydroxyapatite (HA) + 50 wt% TiO2 has been developed on Ti-6Al-4V substrate by plasma spray deposition technique. Followed by plasma spray deposition, detailed surface roughness and microstructural characterization were carried out by using optical profilometer and scanning electron microscopy (SEM), respectively. The composition and phase analysis were carried out by energy-dispersive X-ray spectroscopy analysis, and X-ray diffraction (XRD) technique, respectively. The bio-activity behavior of the uncoated and coated samples was also compared by dipping test in Hank’s solution. The average surface roughness of the coating was 10 µm (as compared to 0.5 µm of as-received Ti-6Al-4V substrate) with the presence of porosities. The microstructure of the coating was found to be continuous with the presence of solidified splats. A detailed XRD analysis shows phase transformation of TiO2 from anatase to rutile, decomposition of hydroxyapatite, and formation of CaTiO3 phase. Standard dipping test confirmed a faster kinetics of deposition of calcium phosphate in the coated HA+50% wt.% TiO2 surface as compared to the as-received substrate.

Keywords: titanium, plasma spraying, microstructure, bio-activity, TiO2, hydroxyapatite

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Authors: Şeyma Saliha Fidan, Ozgur Serin, Ata Mugan

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While performing verification analyses under static and dynamic loads that composite structures used in aviation are exposed to, it is necessary to obtain the bearing strength limit value for mechanically connected composite structures. For this purpose, various tests are carried out in accordance with aviation standards. There are many companies in the world that perform these tests in accordance with aviation standards, but the test costs are very high. In addition, due to the necessity of producing coupons, the high cost of coupon materials, and the long test times, it is necessary to simulate these tests on the computer. For this purpose, various test coupons were produced by using reinforcement and alignment angles of the composite radomes, which were integrated into the aircraft. Glass fiber reinforced and Quartz prepreg is used in the production of the coupons. The simulations of the tests performed according to the American Society for Testing and Materials (ASTM) D5961 Procedure C standard were performed on the computer. The analysis model was created in three dimensions for the purpose of modeling the bolt-hole contact surface realistically and obtaining the exact bearing strength value. The finite element model was carried out with the Analysis System (ANSYS). Since a physical break cannot be made in the analysis studies carried out in the virtual environment, a hypothetical break is realized by reducing the material properties. The material properties reduction coefficient was determined as 10%, which is stated to give the most realistic approach in the literature. There are various theories in this method, which is called progressive failure analysis. Because the hashin theory does not match our experimental results, the puck progressive damage method was used in all coupon analyses. When the experimental and numerical results are compared, the initial damage and the resulting force drop points, the maximum damage load values ​​, and the bearing strength value are very close. Furthermore, low error rates and similar damage patterns were obtained in both test and simulation models. In addition, the effects of various parameters such as pre-stress, use of bushing, the ratio of the distance between the bolt hole center and the plate edge to the hole diameter (E/D), the ratio of plate width to hole diameter (W/D), hot-wet environment conditions were investigated on the bearing strength of the composite structure.

Keywords: puck, finite element, bolted joint, composite

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