Search results for: breast shapes
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1271

Search results for: breast shapes

551 Variation in the Morphology of Soft Palate

Authors: Hema Lattupalli

Abstract:

Introduction: The palate forms a partition between the oral cavity and nasal cavity. The palate is made up of two parts hard palate and soft palate. The Hard palate forms the anterior part of the palate, the soft palate forms a movable muscular fold covered by mucous membrane that is suspended from the posterior border of a hard palate. Aim and Objectives: Soft palate morphological variations have a great paucity in the literature. It’s also believed that the soft palate has no such important anatomical variations. There is a variable presentation of the soft palate morphology in the lateral cephalograms. The aim of this study is to identify the velar morphology. Materials and Methods: 100 normal subjects between the age group of 20 – 35 were taken for the study. Method: Lateral Cephalogram (radiologic study). Results: Different shapes of the soft palate were observed in the lateral cephalograms. The morphology of soft palate was classified into six types 1.Leaf like (50 cases) most common type, 2.Straight line (20 cases), 3.S shaped (4 cases) very rare, 4.Butt like (10 cases), 5. Rat tail (6 cases), 6. Hook shaped (10 cases). Conclusion: This classification helps us to understand the better diversity of the velar morphology in mid-sagittal plane. These findings help us to understand the etiology of OSAS.

Keywords: soft palate, cephalometric radiographs, morphology, cleft palate, obstructive sleep apnoea syndrome

Procedia PDF Downloads 363
550 Nano-Sensors: Search for New Features

Authors: I. Filikhin, B. Vlahovic

Abstract:

We focus on a novel type of detection based on electron tunneling properties of double nanoscale structures in semiconductor materials. Semiconductor heterostructures as quantum wells (QWs), quantum dots (QDs), and quantum rings (QRs) may have energy level structure of several hundred of electron confinement states. The single electron spectra of the double quantum objects (DQW, DQD, and DQR) were studied in our previous works with relation to the electron localization and tunneling between the objects. The wave function of electron may be localized in one of the QDs or be delocalized when it is spread over the whole system. The localizing-delocalizing tunneling occurs when an electron transition between both states is possible. The tunneling properties of spectra differ strongly for “regular” and “chaotic” systems. We have shown that a small violation of the geometry drastically affects localization of electron. In particular, such violations lead to the elimination of the delocalized states of the system. The same symmetry violation effect happens if electrical or magnetic fields are applied. These phenomena could be used to propose a new type of detection based on the high sensitivity of charge transport between double nanostructures and small violations of the shapes. It may have significant technological implications.

Keywords: double quantum dots, single electron levels, tunneling, electron localizations

Procedia PDF Downloads 505
549 Effect of Multi-Stage Fractured Patterns on Production Improvement of Horizontal Wells

Authors: Armin Shirbazo, Mohammad Vahab, Hamed Lamei Ramandi, Jalal Fahimpour

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One of the most effective ways for increasing production in wells that are faced with problems such as pressure depletion and low rate is hydraulic fracturing. Hydraulic fracturing is creating a high permeable path through the reservoir and simulated area around the wellbore. This is very important for low permeability reservoirs, which their production is uneconomical. In this study, the influence of the fracturing pattern in multi-stage fractured horizontal wells is analyzed for a tight, heavy oil reservoir to explore the impact of fracturing patterns on improving oil recovery. The horizontal well has five transverse fractures with the same fracture length, width, height, and conductivity properties. The fracture patterns are divided into four distinct shapes: uniform shape, diamond shape, U shape, and W shape. The results show that different fracturing patterns produce various cumulative production after ten years, and the best pattern can be selected based on the most cumulative production. The result also illustrates that optimum design in fracturing can boost the production up to 3% through the permeability distribution around the wellbore and reservoir.

Keywords: multi-stage fracturing, horizontal well, fracture patterns, fracture length, number of stages

Procedia PDF Downloads 222
548 Logic and Arabic Grammar Debates at Medieval Ages: A Quest for Muslim Contributions to Philosophical Development

Authors: Umar Sheikh Tahir

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This paper focuses on the historiography of the relationship between Logic and Arabic grammar in the Muslim Medieval Ages (a period between 750 and 1100/ 150 and 500 Ah). This sensation appears in the famous debate among many others between grammarians represented by abū Sa'id al-Sairafī and logicians represented by abū Bishr Mattā on Logic and its validity. This incident took place in Baghdad around 932 AD. However, this study singlehandedly samples these debates as the base for the contributions of Islamic philosophers to philosophy of language as well as Epistemology. The question that shapes this research is: What is the intellectual development for Muslim thinkers to philosophy of language in regards to this debate? The current research addresses the Arabic grammar and logical debates by conducting historiography to emphasize on Islamic philosophers’ concerns about this issue. Consequently, this debate generates philosophical phenomena and resolutions in deep-thinking. In addition, these dialogues create a language impression for Philosophy in Islamic world from the period under study. Thereupon, Islamic philosophers’ discourse on this phenomenon serves as contribution to the Philosophy of Language.

Keywords: debates, epistemology, grammar and grammarians, Islamic philosophy, philosophy language, logic

Procedia PDF Downloads 224
547 Blood Thicker Than Water: A Case Report on Familial Ovarian Cancer

Authors: Joanna Marie A. Paulino-Morente, Vaneza Valentina L. Penolio, Grace Sabado

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Ovarian cancer is extremely hard to diagnose in its early stages, and those afflicted at the time of diagnosis are typically asymptomatic and in the late stages of the disease, with metastasis to other organs. Ovarian cancers often occur sporadically, with only 5% associated with hereditary mutations. Mutations in the BRCA1 and BRCA2 tumor suppressor genes have been found to be responsible for the majority of hereditary ovarian cancers. One type of ovarian tumor is Malignant Mixed Mullerian Tumor (MMMT), which is a very rare and aggressive type, accounting for only 1% of all ovarian cancers. Reported is a case of a 43-year-old G3P3 (3003), who came into our institution due to a 2-month history of difficulty of breathing. Family history reveals that her eldest and younger sisters both died of ovarian malignancy, with her younger sister having a histopathology report of endometrioid ovarian carcinoma, left ovary stage IIIb. She still has 2 asymptomatic sisters. Physical examination pointed to pleural effusion of right lung, and presence of bilateral ovarian new growth, which had a Sassone score of 13. Admitting Diagnosis was G3P3 (3003), Ovarian New Growth, bilateral, Malignant; Pleural effusion secondary to malignancy. BRCA was requested to establish a hereditary mutation; however, the patient had no funds. Once the patient was stabilized, TAHBSO with surgical staging was performed. Intraoperatively, the pelvic cavity was occupied by firm, irregularly shaped ovaries, with a colorectal metastasis. Microscopic sections from both ovaries and the colorectal metastasis had pleomorphic tumor cells lined by cuboidal to columnar epithelium exhibiting glandular complexity, displaying nuclear atypia and increased nuclear-cytoplasmic ratio, which are infiltrating the stroma, consistent with the features of Malignant Mixed Mullerian Tumor, since MMMT is composed histologically of malignant epithelial and sarcomatous elements. In conclusion, discussed is the clinic-pathological feature of a patient with primary ovarian Malignant Mixed Mullerian Tumor, a rare malignancy comprising only 1% of all ovarian neoplasms. Also, by understanding the hereditary ovarian cancer syndromes and its relation to this patient, it cannot be overemphasized that a comprehensive family history is really fundamental for early diagnosis. The familial association of the disease, given that the patient has two sisters who were diagnosed with an advanced stage of ovarian cancer and succumbed to the disease at a much earlier age than what is reported in the general population, points to a possible hereditary syndrome which occurs in only 5% of ovarian neoplasms. In a low-resource setting, being in a third world country, the following will be recommended for monitoring and/or screening women who are at high risk for developing ovarian cancer, such as the remaining sisters of the patient: 1) Physical examination focusing on the breast, abdomen, and rectal area every 6 months. 2) Transvaginal sonography every 6 months. 3) Mammography annually. 4) CA125 for postmenopausal women. 5) Genetic testing for BRCA1 and BRCA2 will be reserved for those who are financially capable.

Keywords: BRCA, hereditary breast-ovarian cancer syndrome, malignant mixed mullerian tumor, ovarian cancer

Procedia PDF Downloads 289
546 Proximate, Functional and Sensory Evaluation of Some Brands of Instant Noodles in Nigeria

Authors: Olakunle Moses Makanjuola, Adebola Ajayi

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Noodles are made from unleavened dough, rolled flat and cut into shapes. The instant noodle market is growing fast in Asian countries and is gaining popularity in the western market. This project reports on the proximate functional and sensory evaluation of different brands of instant noodles in Nigeria. The comparisons were based on proximate functional and sensory evaluation of the product. The result obtained from the proximate analysis showed that sample QHR has the highest moisture content, sample BMG has the highest protein content, sample CPO has the highest fat content, sample. The obtained result from the functional properties showed that sample BMG (Dangote noodles) had the highest volume increase after cooking due to its high swelling capacity, high water absorption capacity and high hydration capacity. Sample sensory analysis of the noodles showed that all the samples are of significant difference (at P < 0.05) in terms of colour, texture, and aroma but there is no significant difference in terms of taste and overall acceptability. Sample QHR (Indomie noodles) is the most preferred by the panelists.

Keywords: proximate, functional, sensory evaluation, noodles

Procedia PDF Downloads 253
545 Thermal Buckling Response of Cylindrical Panels with Higher Order Shear Deformation Theory—a Case Study with Angle-Ply Laminations

Authors: Humayun R. H. Kabir

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An analytical solution before used for static and free-vibration response has been extended for thermal buckling response on cylindrical panel with anti-symmetric laminations. The partial differential equations that govern kinematic behavior of shells produce five coupled differential equations. The basic displacement and rotational unknowns are similar to first order shear deformation theory---three displacement in spatial space, and two rotations about in-plane axes. No drilling degree of freedom is considered. Boundary conditions are considered as complete hinge in all edges so that the panel respond on thermal inductions. Two sets of double Fourier series are considered in the analytical solution process. The sets are selected that satisfy mixed type of natural boundary conditions. Numerical results are presented for the first 10 eigenvalues, and first 10 mode shapes for Ux, Uy, and Uz components. The numerical results are compared with a finite element based solution.

Keywords: higher order shear deformation, composite, thermal buckling, angle-ply laminations

Procedia PDF Downloads 372
544 Human Microbiome Hidden Association with Chronic and Autoimmune Diseases

Authors: Elmira Davasaz Tabrizi, Müşteba Sevil, Ercan Arican

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In recent decades, there has been a sharp increase in the prevalence of several unrelated chronic diseases. The use of long-term antibiotics for chronic illnesses is increasing. The antibiotic resistance occurrence and its relationship with host microbiomes are still unclear. Properties of the identifying antibodies have been the focus of chronic disease research, such as prostatitis or autoimmune. The immune system is made up of a complicated but well-organized network of cell types that constantly monitor and maintain their surroundings. The regulated homeostatic interaction between immune system cells and their surrounding environment shapes the microbial flora. Researchers believe that the disappearance of special bacterial species from our ancestral microbiota might have altered the body flora that can cause a rise in disease during the human life span. This unpleasant pattern demonstrates the importance of focusing on discovering and revealing the root causes behind the disappearance or alteration of our microbiota. In this review, we gathered the results of some studies that reveal changes in the diversity and quantity of microorganisms that may affect chronic and autoimmune diseases. Additionally, a Ph.D. thesis that is still in process as Metagenomic studies in chronic prostatitis samples is mentioned.

Keywords: metagenomic, autoimmune, prostatitis, microbiome

Procedia PDF Downloads 96
543 Structural Health Monitoring of Buildings and Infrastructure

Authors: Mojtaba Valinejadshoubi, Ashutosh Bagchi, Osama Moselhi

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Structures such as buildings, bridges, dams, wind turbines etc. need to be maintained against various factors such as deterioration, excessive loads, environment, temperature, etc. Choosing an appropriate monitoring system is important for determining any critical damage to a structure and address that to avoid any adverse consequence. Structural Health Monitoring (SHM) has emerged as an effective technique to monitor the health of the structures. SHM refers to an ongoing structural performance assessment using different kinds of sensors attached to or embedded in the structures to evaluate their integrity and safety to help engineers decide on rehabilitation measures. Ability of SHM in identifying the location and severity of structural damages by considering any changes in characteristics of the structures such as their frequency, stiffness and mode shapes helps engineers to monitor the structures and take the most effective corrective actions to maintain their safety and extend their service life. The main objective of this study is to review the overall SHM process specifically determining the natural frequency of an instrumented simply-supported concrete beam using modal testing and finite element model updating.

Keywords: structural health monitoring, natural frequency, modal analysis, finite element model updating

Procedia PDF Downloads 338
542 Numerical and Comparative Analysis between Two Composite Plates Notched in Different Shapes and Repaired by Composite

Authors: Amari Khaoula, Berrahou Mohamed

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The topic of our article revolves around a numerical and comparative analysis between two notched Boron/epoxy plates that are U-shaped and the other V-shaped, cracked, and repaired by a rectangular patch of the same composite material; the finite element method was used for the analytical study and comparison of the results obtained for determining the optimal shape of notch which will give a longer life to the repair. In this context, we studied the variation of the stress intensity factor, the evolution of the damaged area, and the calculation of the ratio of the damaged area according to the crack length and the concentration of the Von Mises stresses as a function of the lengths of the paths. According to the results obtained, we conclude that the notch plate U is the optimal one than notch plate V because it has lower values either for the stress intensity factor (SIF), damaged area ratio (Dᵣ), or the Von Mises stresses.

Keywords: the notch U, the notch V, the finite element method FEM, comparison, rectangular patch, composite, stress intensity factor, damaged area ratio, Von Mises stresses

Procedia PDF Downloads 100
541 Experimental Study of Local Scour Downstream of Cylindrical Bridge Piers

Authors: Mohammed Traeq Shukri

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Scour is a natural phenomenon caused by the erosive action of flowing stream on alluvial beds, which removes the sediment around or near structures located in flowing water. It means the lowering of the riverbed level by water erosions such that there is a tendency to expose the foundations of a structure. It is the result of the erosive action of flowing water, excavating and carrying away material from the bed and banks of streams and from around the piers of bridges. The failure of bridges due to excessive local scour during floods poses a challenging problem to hydraulic engineers. The failure of bridges piers is due to many reasons such as localized scour combined with general riverbed degradation. In this paper, we try to estimate the temporal variation of scour depth at non-uniform cylindrical bridge pier, by experimental work in civil engineering hydraulic laboratories of Gaziantep University on a channel have dimensions of 8.3m length, 0.8m width and 0.9m depth. The experiments will be carried on 20 cm depth of sediment layer having d50=0.4 mm. Three bridge pier shapes having different scaled models will be constructed in a 1.5m of test section in the channel.

Keywords: scour, local scour, bridge piers, scour depth, vortex, horseshoe vortex

Procedia PDF Downloads 164
540 Topology Optimization of the Interior Structures of Beams under Various Load and Support Conditions with Solid Isotropic Material with Penalization Method

Authors: Omer Oral, Y. Emre Yilmaz

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Topology optimization is an approach that optimizes material distribution within a given design space for a certain load and boundary conditions by providing performance goals. It uses various restrictions such as boundary conditions, set of loads, and constraints to maximize the performance of the system. It is different than size and shape optimization methods, but it reserves some features of both methods. In this study, interior structures of the parts were optimized by using SIMP (Solid Isotropic Material with Penalization) method. The volume of the part was preassigned parameter and minimum deflection was the objective function. The basic idea behind the theory was considered, and different methods were discussed. Rhinoceros 3D design tool was used with Grasshopper and TopOpt plugins to create and optimize parts. A Grasshopper algorithm was designed and tested for different beams, set of arbitrary located forces and support types such as pinned, fixed, etc. Finally, 2.5D shapes were obtained and verified by observing the changes in density function.

Keywords: Grasshopper, lattice structure, microstructures, Rhinoceros, solid isotropic material with penalization method, TopOpt, topology optimization

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539 The Power House of Mind: Determination of Action

Authors: Sheetla Prasad

Abstract:

The focus issue of this article is to determine the mechanism of mind with geometrical analysis of human face. Research paradigm has been designed for study of spatial dynamic of face and it was found that different shapes of face have their own function for determine the action of mind. The functional ratio (FR) of face has determined the behaviour operation of human beings. It is not based on the formulistic approach of prediction but scientific dogmatism and mathematical analysis is the root of the prediction of behaviour. For analysis, formulae were developed and standardized. It was found that human psyche is designed in three forms; manipulated, manifested and real psyche. Functional output of the psyche has been determined by degree of energy flow in the psyche and reserve energy for future. Face is the recipient and transmitter of energy but distribution and control is the possible by mind. Mind directs behaviour. FR indicates that the face is a power house of energy and as per its geometrical domain force of behaviours has been designed and actions are possible in the nature of individual. The impact factor of this study is the promotion of human capital for job fitness objective and minimization of criminalization in society.

Keywords: functional ratio, manipulated psyche, manifested psyche, real psyche

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538 An Experimental Study of Downstream Structures on the Flow-Induced Vibrations Energy Harvester Performances

Authors: Pakorn Uttayopas, Chawalit Kittichaikarn

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This paper presents an experimental investigation for the characteristics of an energy harvesting device exploiting flow-induced vibration in a wind tunnel. A stationary bluff body is connected with a downstream tip body via an aluminium cantilever beam. Various lengths of aluminium cantilever beam and different shapes of downstream tip body are considered. The results show that the characteristics of the energy harvester’s vibration depend on both the length of the aluminium cantilever beam and the shape of the downstream tip body. The highest ratio between vibration amplitude and bluff body diameter was found to be 1.39 for an energy harvester with a symmetrical triangular tip body and L/D1 = 5 at 9.8 m/s of flow speed (Re = 20077). Using this configuration, the electrical energy was extracted with a polyvinylidene fluoride (PVDF) piezoelectric beam with different load resistances, of which the optimal value could be found on each Reynolds number. The highest power output was found to be 3.19 µW, at 9.8 m/s of flow speed (Re = 20077) and 27 MΩ of load resistance.

Keywords: downstream structures, energy harvesting, flow-induced vibration, piezoelectric material, wind tunnel

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537 Mannequin Evaluation of 3D-Printed Intermittent Oro-Esophageal Tube Guide for Dysphagia

Authors: Yujin Jeong, Youkyung Son, Myounghwan Choi, Sanghyub Lee, Sangyeol Lee, Changho Hwang, Kyo-in Koo

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Dysphasia is difficulty in swallowing food because of oral cavity impairments induced by stroke, muscle damage, tumor. Intermittent oro-esophageal (IOE) tube feeding is one of the well-known feeding methods for the dysphasia patients. However, it is hard to insert at the proper position in esophagus. In this study, we design and fabricate the IOE tube guide using 3-dimensional (3D) printer. The printed IOE tube is tested in a mannequin (Airway Management Trainer, Co., Ltd., Copenhagen, Denmark) mimicking human’s esophagus. The gag reflex point is measured as the design point in the mannequin. To avoid the gag reflex, we design various shapes of IOE tube guide. One structure is separated into three parts; biting part, part through oral cavity, connecting part to oro-esophageal. We designed 6 types of IOE tube guide adjusting length and angle of these three parts. To evaluate the IOE tube guide, it is inserted in the mannequin, and through the inserted guide, an endoscopic camera successfully arrived at the oro-esophageal. We had planned to apply this mannequin-based design experience to patients in near future.

Keywords: dysphagia, feeding method, IOE tube guide, 3-D printer

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536 Prevalence of Sarcocystosis in Slaughtered Sheep and Goats

Authors: Shivan N. Hussein, Ihsan K. Zangana

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A total of 2358 sheep and 532 goats were examined for the presence of macrocystis of Sarcocystis. For microcysts, different muscle tissues were randomly taken from 118 sheep and 110 goats. Macrocystis were examined through naked eye inspection, while microcysts were examined microscopically by using histopathology, pepsin digestion, mincing & squeezing, and muscle squash method. Overall prevalence of macrocystis was 1.2% in sheep and 2.6% in goats. The intensity rate of the cysts was 4 cysts/ gram in sheep & 3 cysts/ gram in goats, respectively, while the overall prevalence of microcysts in sheep and goats was 96.5%. The infection rate in sheep was 96.6% and in goats was 96.4%. The total intensity rate of microcysts was 32.4 cysts/ field in sheep and 16.8 cysts/ field in goats, respectively. Histopathological examination found different shapes, size, wall thickness, and intensity rates of microcysts in muscle tissues of sheep & goats. The pathological reaction showed mild to moderate granulocytosis, and mononuclear cells infiltrated surrounding the microcysts with necrotizing and degeneration of myofibrils. The largest average size of spindle and round shaped cysts (290 ± 89.7 x 76.1 ± 10 µm and 88.8 ± 10.3 µm) in goats and (127.2 ± 18.9 x 53.3 ± 5.4 µm and 74.4 ± 7.5 µm) in sheep, was detected in the esophageal muscle. Statistically, there was a significant difference (p < 0.05) in the prevalence of macrocystis in sheep and goats, while no significant difference (p > 0.05) was observed in the prevalence of microcysts between both animal species.

Keywords: macrocystis, microcysts, intensity rate, measurement size

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535 Development of Swing Valve for Gasoline Turbocharger Using Hybrid Metal Injection Molding

Authors: B. S. So, Y. H. Yoon, J. O. Jung, K. S. Bae

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Metal Injection Molding (MIM) is a technology that combines powder metallurgy and injection molding. Particularly, it is widely applied to the manufacture of precision mobile parts and automobile turbocharger parts because compact precision parts with complicated three-dimensional shapes that are difficult to machining are formed into a large number of finished products. The swing valve is a valve that adjusts the boost pressure of the turbocharger. Since the head portion is exposed to the harsh temperature condition of about 900 degrees in the gasoline GDI engine, it is necessary to use Inconel material with excellent heat resistance and abrasion resistance, resulting in high manufacturing cost. In this study, we developed a swing valve using a metal powder injection molding based hybrid material (Inconel 713C material with heat resistance is applied to the head part, and HK30 material with low price is applied to the rest of the body part). For this purpose, the process conditions of the metal injection molding were optimized to minimize the internal defects, and the effectiveness was confirmed by the fracture strength and fatigue test.

Keywords: hybrid metal injection molding, swing valve, turbocharger, double injection

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534 Analytical Model of Locomotion of a Thin-Film Piezoelectric 2D Soft Robot Including Gravity Effects

Authors: Zhiwu Zheng, Prakhar Kumar, Sigurd Wagner, Naveen Verma, James C. Sturm

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Soft robots have drawn great interest recently due to a rich range of possible shapes and motions they can take on to address new applications, compared to traditional rigid robots. Large-area electronics (LAE) provides a unique platform for creating soft robots by leveraging thin-film technology to enable the integration of a large number of actuators, sensors, and control circuits on flexible sheets. However, the rich shapes and motions possible, especially when interacting with complex environments, pose significant challenges to forming well-generalized and robust models necessary for robot design and control. In this work, we describe an analytical model for predicting the shape and locomotion of a flexible (steel-foil-based) piezoelectric-actuated 2D robot based on Euler-Bernoulli beam theory. It is nominally (unpowered) lying flat on the ground, and when powered, its shape is controlled by an array of piezoelectric thin-film actuators. Key features of the models are its ability to incorporate the significant effects of gravity on the shape and to precisely predict the spatial distribution of friction against the contacting surfaces, necessary for determining inchworm-type motion. We verified the model by developing a distributed discrete element representation of a continuous piezoelectric actuator and by comparing its analytical predictions to discrete-element robot simulations using PyBullet. Without gravity, predicting the shape of a sheet with a linear array of piezoelectric actuators at arbitrary voltages is straightforward. However, gravity significantly distorts the shape of the sheet, causing some segments to flatten against the ground. Our work includes the following contributions: (i) A self-consistent approach was developed to exactly determine which parts of the soft robot are lifted off the ground, and the exact shape of these sections, for an arbitrary array of piezoelectric voltages and configurations. (ii) Inchworm-type motion relies on controlling the relative friction with the ground surface in different sections of the robot. By adding torque-balance to our model and analyzing shear forces, the model can then determine the exact spatial distribution of the vertical force that the ground is exerting on the soft robot. Through this, the spatial distribution of friction forces between ground and robot can be determined. (iii) By combining this spatial friction distribution with the shape of the soft robot, in the function of time as piezoelectric actuator voltages are changed, the inchworm-type locomotion of the robot can be determined. As a practical example, we calculated the performance of a 5-actuator system on a 50-µm thick steel foil. Piezoelectric properties of commercially available thin-film piezoelectric actuators were assumed. The model predicted inchworm motion of up to 200 µm per step. For independent verification, we also modelled the system using PyBullet, a discrete-element robot simulator. To model a continuous thin-film piezoelectric actuator, we broke each actuator into multiple segments, each of which consisted of two rigid arms with appropriate mass connected with a 'motor' whose torque was set by the applied actuator voltage. Excellent agreement between our analytical model and the discrete-element simulator was shown for both for the full deformation shape and motion of the robot.

Keywords: analytical modeling, piezoelectric actuators, soft robot locomotion, thin-film technology

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533 Lifetime Assessment of Highly Efficient Metal-Based Air-Diffuser through Accelerated Degradation Test

Authors: Jinyoung Choi, Tae-Ho Yoon, Sunmook Lee

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Degradation of standard oxygen transfer efficiency (SOTE) with time was observed for the assessment of lifetime of metal-based air-diffuser, which displaced a polymer composite-based air-diffuser in order to attain a longer lifetime in the actual field. The degradation of air-diffuser occurred due to the failure of the formation of small and uniform air bubbles since the patterns formed on the disc of air-diffuser deteriorated and/or changed from their initial shapes while they were continuously exposed to the air blowing condition during the operation in the field. Therefore, the lifetime assessment of metal-based air-diffuser was carried out through an accelerated degradation test by accelerating the air-blowing conditions in 200 L/min, 300 L/min, and 400 L/min and the lifetime of normal operating condition at 120 L/min was predicted. It was found that Weibull distribution was the most proper one for describing the lifetime distribution of metal-based air-diffuser in the present study. The shape and scale parameters indicated that the accelerated blowing conditions were all within the acceleration domain. The lifetime was predicted by adopting inverse power model for a stress-life relationship and estimated to be B10=94,004 hrs with CL=95%. Acknowledgement: This work was financially supported by the Ministry of Trade, Industry and Energy (Grant number: N0001475).

Keywords: accelerated degradation test, air-diffuser, lifetime assessment, SOTE

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532 Confinement and Storage of Cyanate in the Nano Scale via Nanolayered Structures

Authors: Osama Saber

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Cyanate is one such anion which is produced during protein poisoning in the body and has been studied extensively in the field of biochemistry because of its toxicity. The present work aims at confinement and storage of cyanate in the nano scale. It was achieved through the intercalation of cyanate anions into nanolayerd structures of Ni-Al LDH. In addition, the effect of aging time on the intercalation of cyanate was clarified using X-ray diffraction and scanning electron microscopy. Furthermore, the effect of cations on the affinity towards the intercalation of cyanate anions inside LDH structure was studied by replacement of tetra-valent cations Ti4+ instead of the tri-vallent cations Al3+ during the preparation of LDH structure. X-ray diffraction patterns of the Ni-Ti LDH showed that the interlayer spacing was 0.73 nm. This spacing was smaller than that of Ni-Al LDH suggesting that the interlayered anions into Ni-Ti LDH are different from those into Ni-Al LDH. Thermal analyses (TG, DTG, and DTA) and Infra-red spectra revealed the presence of only cyanate anions into Ni-Ti LDH while, in the case of Ni-Al LDH, both cyanate and carbonate anions were observed. SEM images showed plate-like morphology for both Ni-Ti and Ni-Al LDHs although the shapes of their plates are not similar. Our results suggested that the LDH structures containing titanium cations have higher affinity for cyanate anions than those containing aluminum cations. Therefore, this choice for cyanate in the interlayered spacing widens the applicability to study the effect of the confinement on the toxicity of cyanate by bio researchers.

Keywords: nanolayered structures, Ni-Al LDH, Ni-Ti LDH, intercalation of cyanate anions, urea hydrolysis

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531 Fiber-Optic Sensors for Hydrogen Peroxide Vapor Measurement

Authors: H. Akbari Khorami, P. Wild, N. Djilali

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This paper reports on the response of a fiber-optic sensing probe to small concentrations of hydrogen peroxide (H2O2) vapor at room temperature. H2O2 has extensive applications in industrial and medical environments. Conversely, H2O2 can be a health hazard by itself. For example, H2O2 induces cellular damage in human cells and its presence can be used to diagnose illnesses such as asthma and human breast cancer. Hence, development of reliable H2O2 sensor is of vital importance to detect and measure this species. Ferric ferrocyanide, referred to as Prussian blue (PB), was deposited on the tip of a multimode optical fiber through the single source precursor technique and served as an indicator of H2O2 in a spectroscopic manner. Sensing tests were performed in H2O2-H2O vapor mixtures with different concentrations of H2O2. The results of sensing tests show the sensor is able to detect H2O2 concentrations in the range of 50.6 ppm to 229.5 ppm. Furthermore, the sensor response to H2O2 concentrations is linear in a log-log scale with the adjacent R-square of 0.93. This sensing behavior allows us to detect and quantify the concentration of H2O2 in the vapor phase.

Keywords: chemical deposition, fiber-optic sensor, hydrogen peroxide vapor, prussian blue

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530 A Novel Dual Band-pass filter Based On Coupling of Composite Right/Left Hand CPW and (CSRRs) Uses Ferrite Components

Authors: Mohammed Berka, Khaled Merit

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Recent works on microwave filters show that the constituent materials such filters are very important in the design and realization. Several solutions have been proposed to improve the qualities of filtering. In this paper, we propose a new dual band-pass filter based on the coupling of a composite (CRLH) coplanar waveguide with complementary split ring resonators (CSRRs). The (CRLH) CPW is composed of two resonators, each one has an interdigital capacitor (CID) and two short-circuited stubs parallel to top ground plane. On the lower ground plane, we use defected ground structure technology (DGS) to engrave two (CSRRs) offered with different shapes and dimensions. Between the top ground plane and the substrate, we place a ferrite layer to control the electromagnetic coupling between (CRLH) CPW and (CSRRs). The global filter that has coplanar access will have a dual band-pass behavior around the magnetic resonances of (CSRRs). Since there’s no scientific or experimental result in the literature for this kind of complicated structure, it was necessary to perform simulation using HFSS Ansoft designer.

Keywords: complementary split ring resonators, coplanar waveguide, ferrite, filter, stub.

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529 Gendered Violence Against Female Students Who Drink Alcohol: Perspectives Of South African Male University Students

Authors: Shakila Singh

Abstract:

Research on gender, sexual risk, and gender violence at universities has found alcohol to be a significant contributor. Studies from universities around the world suggest that drinking at universities is characterised by excess. However, not much attention has been given to the connections that students make between alcohol and violence. In this qualitative study, alcohol-fuelled violence against female students from the perspectives of male students themselves is analysed. In-depth individual interviews were conducted with ten volunteer undergraduate male students who reside in university residences. The findings reveal that alcohol continues to be seen as a masculine privilege. Male students explain that they use alcohol to give them the courage to perform hegemonic heterosexual masculinities. They use alcohol to enhance their capacity to control women. At the same time, they hold alcohol responsible for their loss of control when drunk. Male students also exploit alcohol as currency to coerce women into submission of sexual favours. By blaming alcohol for any deviant behaviour, they relinquish themselves from the responsibility of violating female students. The paper argues that violence prevention efforts in educational contexts must address the ways in which alcohol shapes the experience of gender, sexuality, and violence.

Keywords: alcohol-related violence, gender, and alcohol, hegemonic masculinities, university students

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528 Aerodynamic Analysis of Dimple Effect on Aircraft Wing

Authors: E. Livya, G. Anitha, P. Valli

Abstract:

The main objective of aircraft aerodynamics is to enhance the aerodynamic characteristics and maneuverability of the aircraft. This enhancement includes the reduction in drag and stall phenomenon. The airfoil which contains dimples will have comparatively less drag than the plain airfoil. Introducing dimples on the aircraft wing will create turbulence by creating vortices which delays the boundary layer separation resulting in decrease of pressure drag and also increase in the angle of stall. In addition, wake reduction leads to reduction in acoustic emission. The overall objective of this paper is to improve the aircraft maneuverability by delaying the flow separation point at stall and thereby reducing the drag by applying the dimple effect over the aircraft wing. This project includes both computational and experimental analysis of dimple effect on aircraft wing, using NACA 0018 airfoil. Dimple shapes of Semi-sphere, hexagon, cylinder, square are selected for the analysis; airfoil is tested under the inlet velocity of 30m/s at different angle of attack (5˚, 10˚, 15˚, 20˚, and 25˚). This analysis favours the dimple effect by increasing L/D ratio and thereby providing the maximum aerodynamic efficiency, which provides the enhanced performance for the aircraft.

Keywords: airfoil, dimple effect, turbulence, boundary layer separation

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527 Mapping Iron Content in the Brain with Magnetic Resonance Imaging and Machine Learning

Authors: Gabrielle Robertson, Matthew Downs, Joseph Dagher

Abstract:

Iron deposition in the brain has been linked with a host of neurological disorders such as Alzheimer’s, Parkinson’s, and Multiple Sclerosis. While some treatment options exist, there are no objective measurement tools that allow for the monitoring of iron levels in the brain in vivo. An emerging Magnetic Resonance Imaging (MRI) method has been recently proposed to deduce iron concentration through quantitative measurement of magnetic susceptibility. This is a multi-step process that involves repeated modeling of physical processes via approximate numerical solutions. For example, the last two steps of this Quantitative Susceptibility Mapping (QSM) method involve I) mapping magnetic field into magnetic susceptibility and II) mapping magnetic susceptibility into iron concentration. Process I involves solving an ill-posed inverse problem by using regularization via injection of prior belief. The end result from Process II highly depends on the model used to describe the molecular content of each voxel (type of iron, water fraction, etc.) Due to these factors, the accuracy and repeatability of QSM have been an active area of research in the MRI and medical imaging community. This work aims to estimate iron concentration in the brain via a single step. A synthetic numerical model of the human head was created by automatically and manually segmenting the human head on a high-resolution grid (640x640x640, 0.4mm³) yielding detailed structures such as microvasculature and subcortical regions as well as bone, soft tissue, Cerebral Spinal Fluid, sinuses, arteries, and eyes. Each segmented region was then assigned tissue properties such as relaxation rates, proton density, electromagnetic tissue properties and iron concentration. These tissue property values were randomly selected from a Probability Distribution Function derived from a thorough literature review. In addition to having unique tissue property values, different synthetic head realizations also possess unique structural geometry created by morphing the boundary regions of different areas within normal physical constraints. This model of the human brain is then used to create synthetic MRI measurements. This is repeated thousands of times, for different head shapes, volume, tissue properties and noise realizations. Collectively, this constitutes a training-set that is similar to in vivo data, but larger than datasets available from clinical measurements. This 3D convolutional U-Net neural network architecture was used to train data-driven Deep Learning models to solve for iron concentrations from raw MRI measurements. The performance was then tested on both synthetic data not used in training as well as real in vivo data. Results showed that the model trained on synthetic MRI measurements is able to directly learn iron concentrations in areas of interest more effectively than other existing QSM reconstruction methods. For comparison, models trained on random geometric shapes (as proposed in the Deep QSM method) are less effective than models trained on realistic synthetic head models. Such an accurate method for the quantitative measurement of iron deposits in the brain would be of important value in clinical studies aiming to understand the role of iron in neurological disease.

Keywords: magnetic resonance imaging, MRI, iron deposition, machine learning, quantitative susceptibility mapping

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526 Optimal Design of Propellant Grain Shape Based on Structural Strength Analysis

Authors: Chen Xiong, Tong Xin, Li Hao, Xu Jin-Sheng

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Experiment and simulation researches on the structural integrity of propellant grain in solid rocket motor (SRM) with high volumetric fraction were conducted. First, by using SRM parametric modeling functions with secondary development tool Python of ABAQUS, the three dimensional parameterized modeling programs of star shaped grain, wheel shaped grain and wing cylindrical grain were accomplished. Then, the mechanical properties under different loads for star shaped grain were obtained with the application of automatically established finite element model in ABAQUS. Next, several optimization algorithms are introduced to optimize the star shaped grain, wheel shaped grain and wing cylindrical grain. After meeting the demands of burning surface changes and volumetric fraction, the optimum three dimensional shapes of grain were obtained. Finally, by means of parametric modeling functions, pressure data of SRM’s cold pressurization test was directly applied to simulation of grain in terms of mechanical performance. The results verify the reliability and practical of parameterized modeling program of SRM.

Keywords: cold pressurization test, ğarametric modeling, structural integrity, propellant grain, SRM

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525 Application of Rapid Prototyping to Create Additive Prototype Using Computer System

Authors: Meftah O. Bashir, Fatma A. Karkory

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Rapid prototyping is a new group of manufacturing processes, which allows fabrication of physical of any complexity using a layer by layer deposition technique directly from a computer system. The rapid prototyping process greatly reduces the time and cost necessary to bring a new product to market. The prototypes made by these systems are used in a range of industrial application including design evaluation, verification, testing, and as patterns for casting processes. These processes employ a variety of materials and mechanisms to build up the layers to build the part. The present work was to build a FDM prototyping machine that could control the X-Y motion and material deposition, to generate two-dimensional and three-dimensional complex shapes. This study focused on the deposition of wax material. This work was to find out the properties of the wax materials used in this work in order to enable better control of the FDM process. This study will look at the integration of a computer controlled electro-mechanical system with the traditional FDM additive prototyping process. The characteristics of the wax were also analysed in order to optimize the model production process. These included wax phase change temperature, wax viscosity and wax droplet shape during processing.

Keywords: rapid prototyping, wax, manufacturing processes, shape

Procedia PDF Downloads 464
524 Cytotoxic Metabolites from Tagetes minuta L. Growing in Saudi Arabia

Authors: Ali A. A. Alqarni, Gamal A. Mohamed, Hossam M. Abdallah, Sabrin R. M. Ibrahim

Abstract:

Phytochemical investigation of the methanolic extract of aerial parts of Tagetes minuta L. (Family: Asteraceae) using different chromatographic techniques led to the isolation of five compounds; ecliptal (1), scopoletin (2), P-hydroxy benzoic acid (3), patuletin (4), and patuletin-7-O-β-D-glucopyranoside (5) (Figure 1). Their structures were established based on physical, chemical, and spectral data [Ultraviolet (UV), Proton ¹H, Carbon thirteen ¹³C, and Heteronuclear Multiple Bond Correlation (HMBC) NMR], as well as Electrospray Ionization Mass Spectroscopy (ESIMS) and comparison with literature data. Their cytotoxic activity was assessed towards human liver hepatocellular carcinoma (HepG2), human breast cancer (MCF-7), and human colon cancer (HCT116) cancer cell lines using sulphorhodamine B (SRB) assay. It is noteworthy that compound 1 demonstrated a significant cytotoxic potential towards HepG2, MCF7, and HCT116 cells with IC₅₀s ranging from 2.74 to 7.01 μM, compared to doxorubicin (IC₅₀ 0.18, 0.60, and 0.20 μM, respectively), whereas compounds 2, 4, and 5 showed moderate cytotoxic potential with IC50s ranging from 11.71 to 35.64 μM. However, 3 was inactive up to a concentration of 100 μM towards the three tested cancer cell lines.

Keywords: Asteraceae, cytotoxicity, metabolites, Tagetes minuta

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523 Effectiveness of Column Geometry in High-Rise Buildings

Authors: Man Singh Meena

Abstract:

Structural engineers are facing different kind of challenges due to innovative & bold ideas of architects who are trying to design every structure with uniqueness. In RCC frame structures different geometry of columns can be used in design and rectangular columns can be placed with different type orientation. The analysis is design of structures can also be carried out by different type of software available i.e., STAAD Pro, ETABS and TEKLA. In recent times high-rise building modeling & analysis is done by ETABS due to its certain features which are superior to other software. The case study in this paper mainly emphasizes on structural behavior of high rise building for different column shape configurations like Circular, Square, Rectangular and Rectangular with 90-degree Rotation and rectangular shape plan. In all these column shapes the areas of columns are kept same to study the effect on design of concrete area is same. Modelling of 20-storeys R.C.C. framed building is done on the ETABS software for analysis. Post analysis of the structure, maximum bending moments, shear forces and maximum longitudinal reinforcement are computed and compared for three different story structures to identify the effectiveness of geometry of column.

Keywords: high-rise building, column geometry, building modelling, ETABS analysis, building design, structural analysis, structural optimization

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522 Automated Ultrasound Carotid Artery Image Segmentation Using Curvelet Threshold Decomposition

Authors: Latha Subbiah, Dhanalakshmi Samiappan

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In this paper, we propose denoising Common Carotid Artery (CCA) B mode ultrasound images by a decomposition approach to curvelet thresholding and automatic segmentation of the intima media thickness and adventitia boundary. By decomposition, the local geometry of the image, its direction of gradients are well preserved. The components are combined into a single vector valued function, thus removes noise patches. Double threshold is applied to inherently remove speckle noise in the image. The denoised image is segmented by active contour without specifying seed points. Combined with level set theory, they provide sub regions with continuous boundaries. The deformable contours match to the shapes and motion of objects in the images. A curve or a surface under constraints is developed from the image with the goal that it is pulled into the necessary features of the image. Region based and boundary based information are integrated to achieve the contour. The method treats the multiplicative speckle noise in objective and subjective quality measurements and thus leads to better-segmented results. The proposed denoising method gives better performance metrics compared with other state of art denoising algorithms.

Keywords: curvelet, decomposition, levelset, ultrasound

Procedia PDF Downloads 340