Search results for: fracture property

Authors: Halimah Al Hifzi, Waseem Al-Talalwah, Shorok Al Dorazi, Hassan Al Mousa, Zainab Al-Hashim, Roger Soames

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The obturator artery is one branches of anterior division of the internal iliac artery. It passes on the lateral wall of pelvis to escape into thigh region via obturator foremen. Based on previous research studies, it found to be extremely variable in origin and course. It may arise from internal or external iliac artery. The current study includes 82 dissected specimens to investigate the origin of the obturator artery and explain the clinical importance. The obturator artery arises from the internal iliac artery in 75% either from its anterior or posterior division in 46.9% or 25% respectively. Further, it arises neither from the anterior nor posterior division of the internal iliac artery but it arises between them in 3.1%. In 25%, the obturator artery arises from the external iliac artery. In case of aneurysmectomy of posterior division, carries a high risk of insufficient of vascular supply for demand structures such as proximal adductors attachment and hip joint. Therefore, vascular surgeons have to pay attention to the posterior division being an origin of the obturator artery beside its usual three classical branches: superior gluteal, iliolumbar and lateral sacral arteries. Further, the obturator artery arising from the external iliac system is in great dangerous of laceration in case of anterior pelvic fracture. Therefore, it may lead to haemorrhagic shock threatening life.

Keywords: obturator artery, external iliac, internal iliac artery, anterior division, posterior division, superior gluteal, iliolumbar and lateral sacral, pubic fracture, aneurysm, shock

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Authors: B. V. Murlimanju

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Background: Scaphoid bone is commonly fractured among all the bones of the wrist. The fracture can damage the arteries and would cause avascular necrosis of the scaphoid. In this present study, the goal was to study the topography and number of nutrient foramina in the scaphoid bones of South Indian population. Methods: We studied 46 human scaphoid bones, among them 20 were left sided and 26 belonged to the right side. The scaphoid bones were available at the department of anatomy of our institution. The scaphoid bones were macroscopically observed for the topography and number of nutrient foramina. The data was collected, tabulated and analyzed. Results: The nutrient foramina were observed in all the scaphoid bones (100%). The locations of the foramina were over the non-articular surfaces in all these scaphoids. They were distributed over the palmar and dorsal surfaces. The foramina were found proximal as well as distal to the mid waist of the scaphoid bone. Their number ranged between 9 and 54 in each scaphoid bone. The number ranged between 2-24 over the palmar surface and 7-36 over the dorsal surface. They ranged between 2-24 proximal to the waist and 3-39 distal to the waist. Conclusion: The knowledge of arterial supply, topography of nutrient foramen and their number is essential to understand the concepts of avascular necrosis of scaphoid bone. It will be enlightening to understand the non-union of the fracture of waist of the scaphoid. The morphological data is required to the operating hand surgeon. We do believe that the present study has provided additional information about the topography and number of nutrient foramina of the human scaphoid bones.

Keywords: avascular necrosis, nutrient foramen, scaphoid, vascular

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Authors: Muhammad Fakhrul Arrazi

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Ibn Taymiyyah is a great figure in Islam. His works have become the reference for many Muslims in implementing the fiqh of Ibadah and Muamalat. This article reviews the concepts that Ibn Taymiyyah has initiated in Halal and Haram, long before the books on Halal and Haram are written by contemporary scholars. There are at least four concepts of Halal and Haram ever spawned by Ibn Taymiyyah. First, the belief of a jurist (Faqih) in a matter that is Haram does not necessarily make the matter Haram. Haram arises from the Quran, Sunnah, Ijma’ and Qiyas as the tarjih. Due to the different opinions among the ulama, we should revisit this concept. Second, if a Muslim involves in a transaction (Muamalat), believes it permissible and gets money from such transaction, then it is legal for other Muslims to transact with the property of this Muslim brother, even if he does not believe that the transactions made by his Muslims brother are permissible. Third, Haram is divided into two; first is Haram because of the nature of an object, such as carrion, blood, and pork. If it is mixed with water or food and alters their taste, color, and smell, the food and water become Haram. Second is Haram because of the way it is obtained such as a stolen item and a broken aqad. If it is mixed with the halal property, the property does not automatically become Haram. Fourth, a treasure whose owners cannot be traced back then it is used for the benefit of the ummah. This study used the secondary data from the classics books by Ibn Taymiyyah, particularly those entailing his views on Halal and Haram. The data were then analyzed by using thematic and comparative approach. It is found that most of the concepts proposed by Ibn Taymiyyah in Halal and Haram correspond the majority’s views in the schools. However, some of his concepts are also in contrary to other scholars. His concepts will benefit the ummah, should it be applied to the contemporary issues.

Keywords: fiqh Muamalat, halal, haram, Ibn Taymiyyah

Procedia PDF Downloads 163

Authors: Asma’a Mahfoud, Abu Bakar Md. Sultan, Abdul Azim Abd, Norhayati Mohd Ali, Novia Admodisastro

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Obfuscation is a practice to make something difficult and complicated. Programming code is ordinarily obfuscated to protect the intellectual property (IP) and prevent the attacker from reverse engineering (RE) a copyrighted software program. Obfuscation may involve encrypting some or all the code, transforming out potentially revealing data, renaming useful classes and variables (identifiers) names to meaningless labels, or adding unused or meaningless code to an application binary. Obfuscation techniques were not performing effectively recently as the reversing tools are able to break the obfuscated code. We propose in this paper a hybrid obfuscation technique that contains three approaches of renaming. Experimentation was conducted to test the effectiveness of the proposed technique. The experimentation has presented a promising result, where the reversing tools were not able to read the code.

Keywords: intellectual property, obfuscation, software security, reverse engineering

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Authors: CarlyWill Sloan

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Racial disparities in criminal justice outcomes are well-documented. However, there is little evidence on the extent to which racial bias by prosecutors is responsible for these disparities. This paper tests for racial bias in conviction by prosecutors. To identify effects, this paper leverages as good as random variation in prosecutor race using detailed administrative data on the case assignment process and case outcomes in New York County, New York. This paper shows that the assignment of an opposite-race prosecutor leads to a 5 percentage point (~ 8 percent) increase in the likelihood of conviction for property crimes. There is no evidence of effects for other types of crimes. Additional results indicate decreased dismissals by opposite-race prosecutors likely drive my property crime estimates.

Keywords: criminal justice, discrimination, prosecutors, racial disparities

Procedia PDF Downloads 172

Authors: B. V. Murlimanju, P. J. Jiji, Latha V. Prabhu, Mangala M. Pai

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Background: The scaphoid is the most commonly fractured bone of the wrist. The fracture may disrupt the vessels and end up as the avascular necrosis of the bone. The objective of the present study was to investigate the morphology and number of the nutrient foramina in the cadaveric dried scaphoid bones of the Indian population. Methods: The present study included 46 scaphoid bones (26 right sided and 20 left sided) which were obtained from the gross anatomy laboratory of our institution. The bones were macroscopically observed for the nutrient foramina and the data was collected with respect to their number. The tabulation of the data and analysis were done. Results: All of our specimens (100%) exhibited the nutrient foramina over the non-articular surfaces. The foramina were observed only over the palmar and dorsal surfaces of the scaphoid bones. The foramina were observed both proximal and distal to the mid waist of the scaphoid bone. The foramen ranged between 9 and 54 in each scaphoid bone. The foramina over the palmar surface ranged between, 2-24 in number. The foramina over the dorsal surface ranged between, 7-36 in number. The foramina proximal to the waist ranged between 2 and 24 in number and distal to the waist ranged between 3 and 39. Conclusion: We believe that the present study has provided additional data about the nutrient foramina of the scaphoid bones. The data is enlightening to the orthopedic surgeon and would help in the hand surgeries. The morphological knowledge of the vasculature, their foramina of entry and their number is required to understand the concepts in the avascular necrosis of the proximal scaphoid and non-union of the fracture at the waist of the scaphoid.

Keywords: avascular necrosis, nutrient, scaphoid, vascular

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Authors: Shubham Damke, Md Imtiaz, Sanchita Dei

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To stimulate the well and to enhance the production from the shaly formations, fracturing is essential. Presently the chiefly employed technology is Hydraulic Fracturing. However Hydraulic Fracturing accompanies itself with problems like disposing large volumes of fracturing wastewater, removal of water from the pores, formation damage due to injection of large amount of chemicals into underground formations and many more. Therefore embarking on the path of innovation new techniques have been developed which uses different gases such as Nitrogen, Carbon dioxide, Frac Oil, LPG, etc. are used as a base fluid for fracturing formation. However LPG proves to be the most favorable of them which eliminates the use of water and chemicals. When using it as a fracturing fluid, within the surface equipment, it is stored, gelled, and proppant blended at a constant pressure. It is then pressurized with high pressure pumps to the required surface injection pressure With lowering the total cost and increasing the productivity, LPG is also very noteworthy for fracturing shale, where if the hydraulic fracturing is done the water ‘swells’ the formation and creates surface tension, both of which inhibit the flow of oil and gas. Also fracturing with LPG increases the effective fracture length and since propane, butane and pentane is used which are already present in the natural gas therefore there is no problem of back flow because these gases get mixed with the natural gas. LPG Fracturing technology can be a promising substitute of the Hydraulic Fracturing, which could substantially reduce the capital cost of fracturing shale and will also restrict the problems with the disposal of water and on the same hand increasing the fracture length and the productivity from the shale.

Keywords: Fracking, Shale, Surface Tension, Viscosity

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Authors: Azeez Shaik, Amit Salvi, B. P. Gautham

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Fiber reinforced polymer resin composite materials are finding wide variety of applications in automotive and aerospace industry because of their high specific stiffness and specific strengths when compared to metals. New class of 2D and 3D textile and woven fabric composites offer excellent fracture toughens as they bridge the cracks formed during fracture. Due to complexity of their fiber architectures and its resulting composite microstructures, optimized design and analysis of these structures is very complicated. A traditional homogenization approach is typically used to analyze structures made up of these materials. This approach usually fails to predict damage initiation as well as damage propagation and ultimate failure of structure made up of woven and textile composites. This study demonstrates a methodology to analyze woven and textile composites by using the multi-level multi-scale modelling approach. In this approach, a geometric repetitive unit cell (RUC) is developed with all its constituents to develop a representative volume element (RVE) with all its constituents and their interaction modeled correctly. The structure is modeled based on the RUC/RVE and analyzed at different length scales with desired levels of fidelity incorporating the damage and failure. The results are passed across (up and down) the scales qualitatively as well as quantitatively from the perspective of material, configuration and architecture.

Keywords: cohesive zone, multi-scale modeling, rate dependency, RUC, woven textiles

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Authors: Shuaibu Umar Abdul

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The essence of any state as well as government is to ensure and advance the security of lives and property of its citizens. As a result, providing security in all spheres ranging from safeguarding the territorial integrity, security of lives and property of the citizens as well as economic emancipation have constitute the core objectives cum national interest of virtually all country’s foreign policy in the world. In view of this imperative above, Nigeria has enshrined in the early part of her 1999 constitution as amended, as its duty and responsibility as a state, to ensure security of lives and property of its citizens. Yet, it does not make any significant shift as it relates to the country’s fundamental security needs as exemplified by the current enormous security challenges that reduced the country’s fortune to the background in all ramifications. The study chooses realist paradigm as theoretical underpinning which emphasizes that exigency of the moment should always take priority in the pursuit of foreign policy. The study is historical, descriptive and narrative in method and character. Data for the study was sourced from secondary sources and analysed via content analysis. The study found out that it is lack of political will on the side of the government to guarantee a just and egalitarian society that will be of benefit to all citizens. This could be more appreciated when looking at the gaps between the theory in Nigerian foreign policy and the practice as exemplified by the action or inaction of the government to ensure security in the state. On this account, the study recommends that until the leaderships in Nigerian foreign policy recognized the need for political will and respect for constitutionalism to ensure security of its citizens and territory, otherwise achieving great Nigeria will remain an illusion.

Keywords: foreign policy, nation, national security, Nigeria, security

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Authors: Meha Alouini, Wissem Mnif, Yasmine Souissi

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This work will be conducted within the framework of the environmental sustainable development. It involves waste recovering into biodiesel fuel. Low cost feedstocks such as waste of frying oil and animal fats have been utilized to replace refined vegetable oil for biodiesel production. Biodiesel which refers to fatty acid methyl esters (FAME) was carried out by both chemical and enzymatic reaction of transesterification. In order to compare the two studied reactions the obtained biodiesel was characterized by determining its esters content and its fuel properties according to the European standard EN 14214. It was noted that the chemical method gave the product with the best physical property. But the biological one was found more effective for obtaining important ester content. Thus it would be interesting to optimize the enzymatic pathway of production of biodiesel to obtain a better property of biodiesel.

Keywords: biodiesel, fatty acid methyl esters, transesterification, waste frying oil, waste beef fat

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Authors: Sanjaya N. Munasinghe, R. Gnanasekeram, Dimuthu Tennakoon

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During the last few years there has been a dramatic increase in the number of motorcyclists in Sri Lankan roads and thus an increase of motorcycle accidents (MCAs) with a heavy death and casualty toll. Extremity injuries due to MCAs cause a heavy burden on government hospitals. However, data on MCA injuries are limited. This study tries to determine the relationship between extremity injuries with protective gears and clothing motorcycle riders were wearing at the time of the accident. Data were collected from 410 motorcycle riders and passengers involved with MCAs and admitted to orthopedic and emergency observation wards in Teaching Hospital Kurunegala with extremity injuries between 1st February 2015 and 31st July 2015 using an interviewer administered questioner. Data were analyzed using SPSS version 17.0. Distal radial fracture is the most common upper extremity injury (12%), and Tibial fracture is the most common and severe lower extremity injury (23%). Very few participants were wearing safety gloves (2%) and jackets (10%). Most of the participants were wearing slippers (66%), short sleeved upper clothing (96%) and light cloth trousers (49%). According to Chi-square test associations were found between footwear and foot injuries (p-value - 0.001, Cramer's v-value - 0.203) and safety jacket and upper extremity injuries (p-value - 0.002, Cramer's v-value - 0.177). The results indicate that using safety gear can minimize the number of injuries in MCA victims. Thus it is necessary to ensure that motorcycle riders and pillion riders use proper safety gear.

Keywords: extremity injuries, fractures, motorcycle accidents, safety gear

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Authors: Tsegay Giday Woldu, Haibin Zhang, Xin Zhang, Yemane Hailu Fissuh

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It is well known that nonlinear conjugate gradient method is one of the widely used first order methods to solve large scale unconstrained smooth optimization problems. Because of the low memory requirement, attractive theoretical features, practical computational efficiency and nice convergence properties, nonlinear conjugate gradient methods have a special role for solving large scale unconstrained optimization problems. Large scale optimization problems are with important applications in practical and scientific world. However, nonlinear conjugate gradient methods have restricted information about the curvature of the objective function and they are likely less efficient and robust compared to some second order algorithms. To overcome these drawbacks, the new modified nonlinear conjugate gradient method is presented. The noticeable features of our work are that the new search direction possesses the sufficient descent property independent of any line search and it belongs to a trust region. Under mild assumptions and standard Wolfe line search technique, the global convergence property of the proposed algorithm is established. Furthermore, to test the practical computational performance of our new algorithm, numerical experiments are provided and implemented on the set of some large dimensional unconstrained problems. The numerical results show that the proposed algorithm is an efficient and robust compared with other similar algorithms.

Keywords: conjugate gradient method, global convergence, large scale optimization, sufficient descent property

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Authors: Jonas Pedro Fabris, Alberth Almeida Amorim Souza, Maria Emilia Camargo, Suzana Leitão Russo

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With the law Nº. 9279, of May 14, 1996, the Brazilian government regulates rights and obligations relating to industrial property considering the economic development of the country as granting patents, trademark registration, registration of industrial designs and other forms of protection copyright. In this study, we show the application of the methodology of Box and Jenkins in the series of deposits of industrial design at the National Institute of Industrial Property for the period from May 1996 to April 2013. First, a graphical analysis of the data was done by observing the behavior of the data and the autocorrelation function. The best model found, based on the analysis of charts and statistical tests suggested by Box and Jenkins methodology, it was possible to determine the model number for the deposit of industrial design, SARIMA (2,1,0)(2,0,0), with an equal to 9.88% MAPE.

Keywords: ARIMA models, autocorrelation, Box and Jenkins Models, industrial design, MAPE, time series

Procedia PDF Downloads 518

Authors: Y.J. Wang, C. Q. Ru

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A key issue of cohesive zone models is how to determine the cohesive zone model parameters based on real material test data. In this paper, uniaxial nominal stress-strain curve (SS curve) is used to determine two key parameters of a cohesive zone model (CZM): The maximum traction and the area under the curve of traction-separation law (TSL). To this end, the true SS curve is obtained based on the nominal SS curve, and the relationship between the nominal SS curve and TSL is derived based on an assumption that the stress for cracking should be the same in both CZM and the real material. In particular, the true SS curve after necking is derived from the nominal SS curve by taking the average of the power law extrapolation and the linear extrapolation, and a damage factor is introduced to offset the true stress reduction caused by the voids generated at the necking zone. The maximum traction of the TSL is equal to the maximum true stress calculated based on the damage factor at the end of hardening. In addition, a simple specimen is modeled by Abaqus/Standard to calculate the critical J-integral, and the fracture energy calculated by the critical J-integral represents the stored strain energy in the necking zone calculated by the true SS curve. Finally, the CZM parameters obtained by the present method are compared to those used in a previous related work for a simulation of the drop-weight tear test.

Keywords: dynamic fracture, cohesive zone model, traction-separation law, stress-strain curve, J-integral

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Authors: Yang Chen

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The property-led regeneration has played an important role in the process of rapid urbanization during the past twenty years in China, but it is also been criticized unsustainable as it always focuses on the economic aspect and overlooks the social issues, especially it has exacerbated the residential segregation in the inner city. Based on author’s studying the area around Nanjing railway station, this paper demonstrates that residential segregation indeed exists in the inner city through synthetic analysis on patterns of residents’ living, consumption and welfare, and to some extent, the segregation distribution characteristics represent in a concentric ring model. According to author’s further investigation on the property right and age of the dwelling buildings, the housing-commercialization-led regeneration is defined as the mainspring of the segregation. To solve these problems, the system of sustainable community should be established in both policy and practice, above all, well-designed public facilities including green infrastructure will be appropriate to promote the residential integration and sustainable development in contemporary China.

Keywords: China, dynamic mechanism, residential segregation, sustainable regeneration

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Authors: Bijit Kalita, K. V. N. Surendra

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Rotating disk is one of the most indispensable parts of a rotating machine. Rotating disk has found many applications in the diverging field of science and technology. In this paper, we have taken into consideration the problem of a heavy spinning disk mounted on a rotor system acted upon by boundary traction. Finite element modelling is used at various loading condition to determine the mixed mode stress intensity factors. The effect of combined shear and normal traction on the boundary is incorporated in the analysis under the action of gravity. The variation near the crack tip is characterized in terms of the stress intensity factor (SIF) with an aim to find the SIF for a wide range of parameters. The results of the finite element analyses carried out on the compressed disk of a belt pulley arrangement using fracture mechanics concepts are shown. A total of hundred cases of the problem are solved for each of the variations in loading arc parameter and crack orientation using finite element models of the disc under compression. All models were prepared and analyzed for the uncracked disk, disk with a single crack at different orientation emanating from shaft hole as well as for a disc with pair of cracks emerging from the same center hole. Curves are plotted for various loading conditions. Finally, crack propagation paths are determined using kink angle concepts.

Keywords: crack-tip deformations, static loading, stress concentration, stress intensity factor

Procedia PDF Downloads 119

Authors: Y. J. Wang, C. Q. Ru

Abstract:

A key issue of cohesive zone models is how to determine the cohesive zone model (CZM) parameters based on real material test data. In this paper, uniaxial nominal stress-strain curve (SS curve) is used to determine two key parameters of a cohesive zone model: the maximum traction and the area under the curve of traction-separation law (TSL). To this end, the true SS curve is obtained based on the nominal SS curve, and the relationship between the nominal SS curve and TSL is derived based on an assumption that the stress for cracking should be the same in both CZM and the real material. In particular, the true SS curve after necking is derived from the nominal SS curve by taking the average of the power law extrapolation and the linear extrapolation, and a damage factor is introduced to offset the true stress reduction caused by the voids generated at the necking zone. The maximum traction of the TSL is equal to the maximum true stress calculated based on the damage factor at the end of hardening. In addition, a simple specimen is simulated by Abaqus/Standard to calculate the critical J-integral, and the fracture energy calculated by the critical J-integral represents the stored strain energy in the necking zone calculated by the true SS curve. Finally, the CZM parameters obtained by the present method are compared to those used in a previous related work for a simulation of the drop-weight tear test.

Keywords: dynamic fracture, cohesive zone model, traction-separation law, stress-strain curve, J-integral

Procedia PDF Downloads 484

Authors: Dorsa Rahi, Arghavan Tonkanbonbi, Soheila Manifar, Behzad Jafvarnejad

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Background and Aim: Intraoral manipulation is performed during endotracheal intubation for general anesthesia, which can traumatize the soft and hard tissue in the oral cavity and cause postoperative pain and discomfort. Dental trauma is the most common complication of intubation. This study aimed to assess the prevalence of dental complications due to intubation in patients hospitalized in Imam Khomeini Hospital during 2018-2019. Materials and Methods: A total of 805 patients presenting to the Cancer Institute of Imam Khomeini Hospital for preoperative anesthesia consultation were randomly enrolled. A dentist interviewed the patients and performed a comprehensive clinical oral examination preoperatively. The patients underwent clinical oral examination by another dentist postoperatively. Results: No significant correlation was found between dental trauma (tooth fracture, tooth mobility, or soft tissue injury) after intubation with the age or gender of patients. According to the Wilcoxon test and McNemar-Bowker Test, the rate of mobility before the intubation was significantly different from that after the intubation (P=0.000). Maxillary central incisors, maxillary left canine and mandibular right and left central incisors had the highest rate of fracture. Conclusion: Mobile teeth before the intubation are at higher risk of avulsion and aspiration during the procedure. Patients with primary temporomandibular joint disorders are more susceptible to post-intubation trismus.

Keywords: oral trauma, dental trauma, intubation, anesthesia

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Authors: M. Ramachandra, G. Dilip Maruthi, R. Rashmi

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This paper aims to study the corrosion property of aluminum matrix nanocomposite of an aluminum alloy (Al-6061) reinforced with zirconium dioxide (ZrO₂) particles. The zirconium dioxide particles are synthesized by solution combustion method. The nanocomposite materials are prepared by mechanical stir casting method, varying the percentage of n-ZrO₂ (2.5%, 5% and 7.5% by weight). The corrosion behavior of base metal (Al-6061) and Al/ZrO₂ nanocomposite in seawater (3.5% NaCl solution) is measured using the potential control method. The corrosion rate is evaluated by Tafel extrapolation technique. The corrosion potential increases with the increase in wt.% of n-ZrO₂ in the nanocomposite which means the decrease in corrosion rate. It is found that on addition of n-ZrO2 particles to the aluminum matrix, the corrosion rate has decreased compared to the base metal.

Keywords: Al6061 alloy, corrosion, solution, stir casting, combustion, potentiostat, zirconium dioxide

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Authors: Oluwagbenga B. Fatile, Felix U. Idu, Olajide T. Sanya

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This paper reports the viability of developing Zn-27Al alloy matrix hybrid composites reinforced with alumina, graphite and fly ash (a solid waste byproduct of coal in thermal power plants). This research work was aimed at developing low cost-high performance Zn-27Al matrix composite with low density. Alumina particulates (Al2O3), graphite added with 0, 2, 3, 4, and 5 wt% fly ash were utilized to prepare 10wt% reinforcing phase with Zn-27Al alloy as matrix using two-step stir casting method. Density measurement estimated percentage porosity, tensile testing, micro hardness measurement, and optical microscopy were used to assess the performance of the composites produced. The results show that the hardness, ultimate tensile strength, and percent elongation of the hybrid composites decrease with increase in fly ash content. The maximum decrease in hardness and ultimate tensile strength of 13.72% and 15.25% respectively were observed for composite grade containing 5wt% fly ash. The percentage elongation of composite sample without fly ash is 8.9% which is comparable with that of the sample containing 2wt% fly ash with percentage elongation of 8.8%. The fracture toughness of the fly ash containing composites was, however, superior to those of composites without fly ash with 5wt% fly ash containing composite exhibiting the highest fracture toughness. The results show that fly ash can be utilized as complementary reinforcement in ZA-27 alloy matrix composite to reduce cost.

Keywords: fly ash, hybrid composite, mechanical behaviour, stir-cast

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Authors: Lalnuntluanga Hmar, Hardik Vyas

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Hydraulic fracturing has become an essential procedure to break apart the rock and release the oil or gas which are trapped tightly in the rock by pumping fracturing fluids at high pressure down into the well. To open the fracture and to transport propping agent along the fracture, proper selection of fracturing fluids is the most crucial components in fracturing operations. Rheology properties of the fluids are usually considered the most important. Among various fracturing fluids, Borate crosslinked fluids have proved to be highly effective. Borate in the form of Boric Acid, borate ion is the most commonly use to crosslink the hydrated polymers and to produce very viscous gels that can stable at high temperature. Guar and HPG (Hydroxypropyl Guar) polymers are the most often used in these fluids. Borate gel rheology is known to be a function of polymer concentration, borate ion concentration, pH, and temperature. The crosslinking using Borate is a function of pH which means it can be formed or reversed simply by altering the pH of the fluid system. The fluid system was prepared by mixing base polymer with water at pH ranging between 8 to 11 and the optimum borate crosslinker efficiency was found to be pH of about 10. The rheology of laboratory prepared Borate crosslinked fracturing fluid was determined using Anton Paar Rheometer and Fann Viscometer. The viscosity was measured at high temperature ranging from 200ᵒF to 250ᵒF and pressures in order to partially stimulate the downhole condition. Rheological measurements reported that the crosslinking increases the viscosity, elasticity and thus fluid capability to transport propping agent.

Keywords: borate, crosslinker, Guar, Hydroxypropyl Guar (HPG), rheology

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Authors: Sai AKhila Budaraju

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Heritage sites are an integral part of cities and carry a sense of identity to the cities/ towns, but the process of urbanization is a carrying potential threat for the loss of these heritage sites/monuments. Both Central and State Governments listed the historic Golconda fort as National Important Monument and the Heritage precinct with eight heritage-listed buildings and two historical sites respectively, for conservation and preservation, due to the presence of IT Corridor 6kms away accommodating more people in the precinct is under constant pressure. The heritage precinct possesses high property values, being a prime location connecting the IT corridor and CBD (central business district )areas. The primary objective of the study was to assess and identify the factors that are affecting the heritage precinct through Mapping and documentation, Identifying and assessing the factors through empirical analysis, Ordinal regression analysis and Hedonic Pricing Model. Ordinal regression analysis was used to identify the factors that contribute to the changes in the precinct due to urbanization. Hedonic Pricing Model was used to understand and establish a relation whether the presence of historical monuments is also a contributing factor to the property value and to what extent this influence can contribute. The above methods and field visit indicates the Physical, socio-economic factors and the neighborhood characteristics of the precinct contributing to the property values. The outturns and the potential elements derived from the analysis of the Development Control Rules were derived as recommendations to Integrate both Old and newly built environments.

Keywords: heritage planning, heritage conservation, hedonic pricing model, ordinal regression analysis

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Authors: H. M. Nanjundaswamy, S. K. Nath, S. Ray

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TiO₂ particles have been added in molten aluminium to result in aluminium based cast Al/Al₃Ti-Al₂O₃ composite, which has been added then to molten magnesium to synthesize magnesium based cast Mg-Al/Al₃Ti-Al₂O₃ composite. The nominal compositions in terms of Mg, Al, and TiO₂ contents in the magnesium based composites are Mg-9Al-0.6TiO₂, Mg-9Al-0.8TiO₂, Mg-9Al-1.0TiO₂ and Mg-9Al-1.2TiO₂ designated respectively as MA6T, MA8T, MA10T and MA12T. The microstructure of the cast magnesium based composite shows grayish rods of intermetallics Al₃Ti, inherited from aluminium based composite but these rods, on hot forging, breaks into smaller lengths decreasing the average aspect ratio (length to diameter) from 7.5 to 3.0. There are also cavities in between the broken segments of rods. β-phase in cast microstructure, Mg₁₇Al₁₂, dissolves during heating prior to forging and re-precipitates as relatively finer particles on cooling. The amount of β-phase also decreases on forging as segregation is removed. In both the cast and forged composite, the Brinell hardness increases rapidly with increasing addition of TiO₂ but the hardness is higher in forged composites by about 80 BHN. With addition of higher level of TiO₂ in magnesium based cast composite, yield strength decreases progressively but there is marginal increase in yield strength over that of the cast Mg-9 wt. pct. Al, designated as MA alloy. But the ultimate tensile strength (UTS) in the cast composites decreases with the increasing particle content indicating possibly an early initiation of crack in the brittle inter-dendritic region and their easy propagation through the interfaces of the particles. In forged composites, there is a significant improvement in both yield strength and UTS with increasing TiO₂ addition and also, over those observed in their cast counterpart, but at higher addition it decreases. It may also be noted that as in forged MA alloy, incomplete recovery of forging strain increases the strength of the matrix in the composites and the ductility decreases both in the forged alloy and the composites. Initiation fracture toughness, J_IC, decreases drastically in cast composites compared to that in MA alloy due to the presence of intermetallic Al₃Ti and Al₂O₃ particles in the composite. There is drastic reduction of J_IC on forging both in the alloy and the composites, possibly due to incomplete recovery of forging strain in both as well as breaking of Al₃Ti rods and the voids between the broken segments of Al₃Ti rods in composites. The ratio of tearing modulus to elastic modulus in cast composites show higher ratio, which increases with the increasing TiO₂ addition. The ratio decreases comparatively more on forging of cast MA alloy than those in forged composites.

Keywords: composite, fracture toughness, forging, tensile properties

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Authors: Carmen Georgeta Dumitrache

Abstract:

Measurements of terrestrial science aims to study the totality of operations and computing, which are carried out for the purposes of representation on the plan or map of the land surface in a specific cartographic projection and topographic scale. With the development of society, the metrics have evolved, and they land, being dependent on the achievement of a goal-bound utility of economic activity and of a scientific purpose related to determining the form and dimensions of the Earth. For measurements in the field, data processing and proper representation on drawings and maps of planimetry and landform of the land, using topographic and geodesic instruments, calculation and graphical reporting, which requires a knowledge of theoretical and practical concepts from different areas of science and technology. In order to use properly in practice, topographical and geodetic instruments designed to measure precise angles and distances are required knowledge of geometric optics, precision mechanics, the strength of materials, and more. For processing, the results from field measurements are necessary for calculation methods, based on notions of geometry, trigonometry, algebra, mathematical analysis and computer science. To be able to illustrate topographic measurements was established for the lifting of property located near the locality of Gircov, Romania. We determine this total surface of the plan (T30), parcel/plot, but also in the field trace the coordinates of a parcel. The purpose of the removal of the planimetric consisted of: the exact determination of the bounding surface; analytical calculation of the surface; comparing the surface determined with the one registered in the documents produced; drawing up a plan of location and delineation with closeness and distance contour, as well as highlighting the parcels comprising this property; drawing up a plan of location and delineation with closeness and distance contour for a parcel from Dave; in the field trace outline of plot points from the previous point. The ultimate goal of this work was to determine and represent the surface, but also to tear off a plot of the surface total, while respecting the first surface condition imposed by the Act of the beneficiary's property.

Keywords: topography, surface, coordinate, modeling

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Authors: Khaled Elbehiery, Hussam Elbehiery

Abstract:

Smart cities are a framework of technologies along with sustainable infrastructure to provide their citizens an improved quality of life, safer environment, affordability, and more, which in turn helps with the society's economic growth. The proposed research will focus on the primary building block of the smart city; the infrastructure of the house itself. The traditional method of building houses has been, for a long time, nothing but a costly manufacturing process, and consequently, buying a house becomes not an option for everyone anymore. The smart cities' Modular Houses are not using traditional building construction materials; the design reduces the common lengthy construction times and associated high costs. The Modular Houses are technological homes, low-cost and customizable based on a family's requirements. In addition, the Modular Houses are environmentally friendly and healthy enough to assist with the pandemic situation.

Keywords: smart cities, modular houses, single-unit property, multi-unit property, mobility features, chain-supply, livable environment, carbon footprint

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Authors: Fanqiang Kong, Chending Bian

Abstract:

In this work, we exploit two assumed properties of the abundances of the observed signatures (endmembers) in order to reconstruct the abundances from hyperspectral data. Joint-sparsity is the first property of the abundances, which assumes the adjacent pixels can be expressed as different linear combinations of same materials. The second property is rank-deficiency where the number of endmembers participating in hyperspectral data is very small compared with the dimensionality of spectral library, which means that the abundances matrix of the endmembers is a low-rank matrix. These assumptions lead to an optimization problem for the sparse unmixing model that requires minimizing a combined l_2,p-norm and nuclear norm. We propose a variable splitting and augmented Lagrangian algorithm to solve the optimization problem. Experimental evaluation carried out on synthetic and real hyperspectral data shows that the proposed method outperforms the state-of-the-art algorithms with a better spectral unmixing accuracy.

Keywords: hyperspectral unmixing, joint-sparse, low-rank representation, abundance estimation

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Authors: M. Peña Aguilar Juan, Valencia Luis, Pastrana Alberto, Nava Estefany, A. Martinez, M. Vivanco, A. Castañeda

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This paper seeks to compare the innovation of Mexico from an economic and human perspective, with the seven most innovative countries according to the Global Innovation Index 2013, done by the World Intellectual Property Organization (WIPO). The above analysis suggests nine dimensions: Expenditure on R & D, intellectual property, appropriate environment to conduct business, economic stability, and triple helix for R & D, ICT Infrastructure, education, human resources and quality of life. Each dimension is represented by an indicator which is later used to construct a radial graph that compares the innovative capacity of the countries analysed. As a result, it is proposed a new indicator of innovation called The Area of Innovation. Observations are made from the results, and finally as a conclusion, those items or dimensions in which Mexico suffers lag in innovation are identify.

Keywords: dimension, measure, innovation level, economy, radar chart

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Authors: Aigul Abduldayeva, Gulnar Tuleshova

Abstract:

Osteoporosis (OP) is a major socio-economic problem and is a major cause of disability, reduced quality of life and premature death of elderly people. In Astana, the study involved 93 respondents, of whom 17 were men (18.3%), and 76 were women (81.7%). Age distribution of the respondents is as follows: 40-59 (66.7%), 60-75 (29.0%), 75-90 (4.3%). In the city of Astana general breach of bone mass (CCM) was determined in 83.8% (nationwide figure - RRP - 79.0%) of the patients, and normal levels of ultrasound densitometry were detected in 16.1% (RRP 21.0%) of the patients. OP was diagnosed in 20.4% of people over 40 (RRP for citizens is 19.0%), 25.4% in the group older than 50 (23.4% PIU), 22,6% in the group older than 60 (RRP 32.6%), 25.0% in the group older than 70 (47.6% of RRP). OPN was detected in 63.4% (RRP 59.6%) of the surveyed population. These data indicate that, there is no sharp difference between Astana and other cities in the country regarding the incidence of OP, that is, the situation with the OP is not aggravated by any regional characteristics. In the distribution of respondents by clusters it was found that 80.0% of the respondents with CCM were in the "best urban cluster", 93.8% were in "average urban cluster", and 77.4% were in a "poor urban cluster". There is a high rate construction of new buildings in Astana, presumably, that the new settlers inhabit the outskirts of the city, and very difficult to trace the socio-economic differences there. Based on these data the following conclusions can be made: 1. According to the ultrasound densitometry of the calcaneus the prevalence rate of NCM among the residents of Astana is 83.3%, OP - 20.4%, which generally coincides with data elsewhere in the country. 2. The urban population of Astana is under a high degree of risk for low energetic fracture, 46.2% of the population had medium and high risks of fracture, while the nationwide index is 26.7%. 3. In the development of CCM residents of Akmola region play a significant role gender, age, ethnic factors. According to the ultrasound densitometry women are more prone to Astana OP - 22.4% of respondents than men - 11.8% of respondents.

Keywords: nutrition, osteoporosis, elderly, urban population

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Authors: Julia Cristina Bonaldo, Christophe L. Martin, Severine Romero Baivier, Stephane Mazerat

Abstract:

Alumina refractories are commonly used in steel and foundry industries. These refractories are prepared through a powder metallurgy route. They are a mixture of hard alumina particles and graphite platelets embedded into a soft carbonic matrix (binder). The powder can be cold pressed isostatically or uniaxially, depending on the application. The compact is then fired to obtain the final product. The quality of the product is governed by the microstructure of the composite and by the process parameters. The compaction behavior and the mechanical properties of the fired product depend greatly on the amount of each phase, on their morphology and on the initial microstructure. In order to better understand the link between these parameters and the macroscopic behavior, we use the Discrete Element Method (DEM) to simulate the compaction process and the fracture behavior of the fired composite. These simulations are coupled with well-designed experiments. Four mixes with various amounts of Al₂O₃ and binder were tested both experimentally and numerically. In DEM, each particle is modelled and the interactions between particles are taken into account through appropriate contact or bonding laws. Here, we model a bimodal mixture of large Al₂O₃ and small Al₂O₃ covered with a soft binder. This composite is itself mixed with graphite platelets. X-ray tomography images are used to analyze the morphologies of the different components. Large Al₂O₃ particles and graphite platelets are modelled in DEM as sets of particles bonded together. The binder is modelled as a soft shell that covers both large and small Al₂O₃ particles. When two particles with binder indent each other, they first interact through this soft shell. Once a critical indentation is reached (towards the end of compaction), hard Al₂O₃ - Al₂O₃ contacts appear. In accordance with experimental data, DEM simulations show that the amount of Al₂O₃ and the amount of binder play a major role for the compaction behavior. The graphite platelets bend and break during the compaction, also contributing to the macroscopic stress. Firing step is modeled in DEM by ascribing bonds to particles which contact each other after compaction. The fracture behavior of the compacted mixture is also simulated and compared with experimental data. Both diametrical tests (Brazilian tests) and triaxial tests are carried out. Again, the link between the amount of Al₂O₃ particles and the fracture behavior is investigated. The methodology described here can be generalized to other particulate materials that are used in the ceramic industry.

Keywords: cold compaction, composites, discrete element method, refractory materials, x-ray tomography

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Authors: José Carlos Rodríguez, Mario Gómez

Abstract:

This paper analyses innovation trends in Latin America countries by means of the number of patent applications filed by residents and non-residents during the period 1965 to 2012. Making use of patent data released by the World Intellectual Property Organization (WIPO), we search for the presence of multiple structural changes in patent application series in Argentina, Brazil Chile, and Mexico. These changes may suggest that firms’ innovative activity has been modified as a result of implementing a particular science, technology and innovation (STI) policy. Accordingly, the new regulations implemented in these countries during 1980s and 1990s have influenced their intellectual property regimes. The question conducting this research is thus how STI policies in these countries have affected their innovation activity? The results achieved in this research confirm the existence of multiple structural changes in the series of patent applications resulting from STI policies implemented in these countries.

Keywords: econometric methods, innovation activity, Latin America countries, patents, science, technology and innovation policy

Procedia PDF Downloads 256