Search results for: resistivity section
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1648

Search results for: resistivity section

1198 Hawaii, Colorado, and Netherlands: A Comparative Analysis of the Respective Space Sectors

Authors: Mclee Kerolle

Abstract:

For more than 50 years, the state of Hawaii has had the beginnings of a burgeoning commercial aerospace presence statewide. While Hawaii provides the aerospace industry with unique assets concerning geographic location, lack of range safety issues and other factors critical to aerospace development, Hawaii’s strategy and commitment for aerospace have been unclear. For this reason, this paper presents a comparative analysis of Hawaii’s space sector with two of the world’s leading space sectors, Colorado and the Netherlands, in order to provide a strategic plan that establishes a firm position going forward to support Hawaii’s aerospace development statewide. This plan will include financial and other economic incentives legislatively supported by the State to help grow and diversify Hawaii’s aerospace sector. The first part of this paper will examine the business model adopted by the Colorado Space Coalition (CSC), a group of industry stakeholders working to make Colorado a center of excellence for aerospace, as blueprint for growth in Hawaii’s space sector. The second section of this paper will examine the business model adopted by the Netherlands Space Business Incubation Centre (NSBIC), a European Space Agency (ESA) affiliated program that offers business support for entrepreneurs to turn space-connected business ideas into commercial companies. This will serve as blueprint to incentivize space businesses to launch and develop in Hawaii. The third section of this paper will analyze the current policies both CSC, and NSBIC implores to promote industry expansion and legislative advocacy. The final section takes the findings from both space sectors and applies their most adaptable features to a Hawaii specific space business model that takes into consideration the unique advantage and disadvantages found in developing Hawaii’s space sector. The findings of this analysis will show that the development of a strategic plan based on a comparative analysis that creates high technology jobs and new pathways for a trained workforce in the space sector, as well as elicit state support and direction, will achieve the goal of establishing Hawaii as a center of space excellence. This analysis will also serve as a signal to the federal, private sector and international community that Hawaii is indeed serious about developing its’ aerospace industry. Ultimately this analysis and subsequent aerospace development plan will serve as a blueprint for the benefit of all space-faring nations seeking to develop their space sectors.

Keywords: Colorado, Hawaii, Netherlands, space policy

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1197 Technological Ensuring of the Space Reflector Antennas Manufacturing Process from Carbon Fiber Reinforced Plastics

Authors: Pyi Phyo Maung

Abstract:

In the study, the calculations of the permeability coefficient, values of the volume and porosity of a unit cell of a woven fabric before and after deformation based on the geometrical parameters are presented. Two types of carbon woven fabric structures were investigated: standard type, which integrated the filament, has a cross sectional shape of a cylinder and spread tow type, which has a rectangular cross sectional shape. The space antennas reflector, which distinctive feature is the presence of the surface of double curvature, is considered as the object of the research. Modeling of the kinetics of the process of impregnation of the reflector for the two types of carbon fabric’s unit cell structures was performed using software RAM-RTM. This work also investigated the influence of the grid angle between warp and welt of the unit cell on the duration of impregnation process. The results showed that decreasing the angle between warp and welt of the unit cell, the decreasing of the permeability values were occurred. Based on the results of calculation samples of the reflectors, their quality was determined. The comparisons of the theoretical and experimental results have been carried out. Comparison of the two textile structures (standard and spread tow) showed that the standard textiles with circular cross section were impregnated faster than spread tows, which have a rectangular cross section.

Keywords: vacuum assistant resin infusion, impregnation time, shear angle, reflector and modeling

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1196 Geotechnical Distress Evaluation of a Damaged Structure

Authors: Zulfiqar Ali, Umar Saleem, Muhammad Junaid, Rizwan Tahir

Abstract:

Gulzar Mahal is a heritage site located in the city of Bahawalpur, Pakistan. The site is under a process of degradation, as cracks are appearing on the walls, roofs, and floor around the building due to differential settlement. To preserve the integrity of the structure, a geotechnical distress evaluation was carried out to evaluate the causal factors and recommend remediation measures. The research involved the characterization of the problematic soil and analysis of the observed distress with respect to the geotechnical properties. Both conventional lab and field tests were used in conjunction with the unconventional techniques like; Electrical Resistivity Tomography (ERT) and FEA. The temporal, geophysical and geotechnical evaluations have concluded that the foundation soil over the past was subjected to variations in the land use, poor drainage patterns, overloading and fluctuations in groundwater table all contributing to the differential settlements manifesting in the form of the visible shear crack across the length and breadth of the building.

Keywords: differential settlement, distress evaluation, finite element analysis, Gulzar Mahal

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1195 Effect of Reynolds Number and Concentration of Biopolymer (Gum Arabic) on Drag Reduction of Turbulent Flow in Circular Pipe

Authors: Kamaljit Singh Sokhal, Gangacharyulu Dasoraju, Vijaya Kumar Bulasara

Abstract:

Biopolymers are popular in many areas, like petrochemicals, food industry and agriculture due to their favorable properties like environment-friendly, availability, and cost. In this study, a biopolymer gum Arabic was used to find its effect on the pressure drop at various concentrations (100 ppm – 300 ppm) with various Reynolds numbers (10000 – 45000). A rheological study was also done by using the same concentrations to find the effect of the shear rate on the shear viscosity. Experiments were performed to find the effect of injection of gum Arabic directly near the boundary layer and to investigate its effect on the maximum possible drag reduction. Experiments were performed on a test section having i.d of 19.50 mm and length of 3045 mm. The polymer solution was injected from the top of the test section by using a peristaltic pump. The concentration of the polymer solution and the Reynolds number were used as parameters to get maximum possible drag reduction. Water was circulated through a centrifugal pump having a maximum 3000 rpm and the flow rate was measured by using rotameter. Results were validated by using Virk's maximum drag reduction asymptote. A maximum drag reduction of 62.15% was observed with the maximum concentration of gum Arabic, 300 ppm. The solution was circulated in the closed loop to find the effect of degradation of polymers with a number of cycles on the drag reduction percentage. It was observed that the injection of the polymer solution in the boundary layer was showing better results than premixed solutions.

Keywords: drag reduction, shear viscosity, gum arabic, injection point

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1194 Lacustrine Sediments of the Poljanska Locality in the Miocene Climatic Optimum North Croatian Basin, Croatia

Authors: Marijan KovačIć, Davor Pavelić, Darko Tibljaš, Ivo Galić, Frane Marković, Ivica PavičIć

Abstract:

The North Croatian Basin (NCB) occupies the southwestern part of the Pannonian Basin System and belongs to the Central Paratethys realm. In a quarry near the village of Poljanska, on the southern slopes of Mt. Papuk in eastern Croatia, a 40-meter-thick section is exposed, consisting of well-bedded, mixed, carbonate-siliciclastic deposits with occurrences of pyroclastics. Sedimentological investigation indicates that a salina lake developed in the central NCB during the late early Miocene. Field studies and mineralogical and petrological analyses indicate that alternations of laminated crypto- characterize the lower part of the section to microcrystalline dolomite and analcimolite (sedimentary rocks composed essentially of authigenic analcime) associated with tuffites and marls. The pyroclastic material is a product of volcanic activity at the end of the early Miocene, while the formation of analcime, the zeolite group mineral, is a result of an alteration of pyroclastic material in an alkaline lacustrine environment. These sediments were deposited in a shallow, hydrologically closed lake that was controlled by an arid climate during the first phase of its development. The middle part of the section consists of dolomites interbedded with analcimolites and sandstones. The sandstone beds are a result of the increased supply of clastic material derived from the locally uplifted metamorphic and granitoid basement. The emplacement of sandstones and dolomites reflects a distinct alternation of hydrologically open and closed lacustrine environments controlled by the frequent alternation of humid and arid climates, representing the second phase of lake development. The siliciclastics of the third phase of lake development were deposited during the Middle Miocene in a hydrologically mostly open lake. All lacustrine deposition coincides with the Miocene Climatic Optimum, which was characterized by a hot and warm climate. The sedimentological data confirm the mostly wet conditions previously identified by paleobotanical studies in the region. The exception is the relatively long interval of arid climate in the late early Miocene that controlled the first phase of lake evolution, i.e., the salina-type lake.

Keywords: early Miocene, Pannonian basin System, pyroclastics, salina-type lake

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1193 A Conceptual Analysis of Right of Taxpayers to Claim Refund in Nigeria

Authors: Hafsat Iyabo Sa'adu

Abstract:

A salient feature of the Nigerian Tax Law is the right of the taxpayer to demand for a refund where excess tax is paid. Section 23 of the Federal Inland Revenue Service (Establishment) Act, 2007 vests Federal Inland Revenue Services with the power to make tax refund as well as set guidelines and requirements for refund process from time to time. In addition, Section 61 of the Federal Inland Revenue Service (Establishment) Act, 2007, empowers the Federal Inland Revenue Services to issue information circular to acquaint stakeholders with the policy on the refund process. A Circular was issued to that effect to correct the position that until after the annual audit of the Service before such excess can be paid to the claimant/taxpayer. But it is amazing that such circular issuance does not feature under the states’ laws. Hence, there is an inconsistencies in the tax paying system in Nigeria. This study, therefore, sets an objective, to examine the trending concept of tax refund in Nigeria. In order to achieve this set objective, a doctrinal study went under way, wherein both federal and states laws were consulted including journals and textbooks. At the end of the research, it was revealed that the law should be specific as to the time frame within which to make the refund. It further revealed that it is essential to put up a legal framework for the tax system to recognize excess payment as debt due from the state. This would provide a foundational framework for the relationship between taxpayers and Federal Inland Revenue Service as well as promote effective tax administration in all the states of the federation. Several Recommendations were made especially relating to legislative passage of ‘’Refund Circular Bill at the states levels’ pursuant to the Federal Inland Revenue Service (Establishment) Act, 2007.

Keywords: claim, Nigeria, refund, right

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1192 The Role of Uterine Artery Embolization in the Management of Postpartum Hemorrhage

Authors: Chee Wai Ku, Pui See Chin

Abstract:

As an emerging alternative to hysterectomy, uterine artery embolization (UAE) has been widely used in the management of fibroids and in controlling postpartum hemorrhage (PPH) unresponsive to other therapies. Research has shown UAE to be a safe, minimally invasive procedure with few complications and minimal effects on future fertility. We present two cases highlighting the use of UAE in preventing PPH in a patient with a large fibroid at the time of cesarean section and in the treatment of secondary PPH refractory to other therapies in another patient. We present a 36-year primiparous woman who booked at 18+6 weeks gestation with a 13.7 cm subserosal fibroid at the lower anterior wall of the uterus near the cervix and a 10.8 cm subserosal fibroid in the left wall. Prophylactic internal iliac artery occlusion balloons were placed prior to the planned classical midline cesarean section. The balloons were inflated once the baby was delivered. Bilateral uterine arteries were embolized subsequently. The estimated blood loss (EBL) was 400 mls and hemoglobin (Hb) remained stable at 10 g/DL. Ultrasound scan 2 years postnatally showed stable uterine fibroids 10.4 and 7.1 cm, which was significantly smaller than before. We present the second case of a 40-year-old G2P1 with a previous cesarean section for failure to progress. There were no antenatal problems, and the placenta was not previa. She presented with term labour and underwent an emergency cesarean section for failed vaginal birth after cesarean. Intraoperatively extensive adhesions were noted with bladder drawn high, and EBL was 300 mls. Postpartum recovery was uneventful. She presented with secondary PPH 3 weeks later complicated by hypovolemic shock. She underwent an emergency examination under anesthesia and evacuation of the uterus, with EBL 2500mls. Histology showed decidua with chronic inflammation. She was discharged well with no further PPH. She subsequently returned one week later for secondary PPH. Bedside ultrasound showed that the endometrium was thin with no evidence of retained products of conception. Uterotonics were administered, and examination under anesthesia was performed, with uterine Bakri balloon and vaginal pack insertion after. EBL was 1000 mls. There was no definite cause of PPH with no uterine atony or products of conception. To evaluate a potential cause, pelvic angiogram and super selective left uterine arteriogram was performed which showed profuse contrast extravasation and acute bleeding from the left uterine artery. Superselective embolization of the left uterine artery was performed. No gross contrast extravasation from the right uterine artery was seen. These two cases demonstrated the superior efficacy of UAE. Firstly, the prophylactic use of intra-arterial balloon catheters in pregnant patients with large fibroids, and secondly, in the diagnosis and management of secondary PPH refractory to uterotonics and uterine tamponade. In both cases, the need for laparotomy hysterectomy was avoided, resulting in the preservation of future fertility. UAE should be a consideration for hemodynamically stable patients in centres with access to interventional radiology.

Keywords: fertility preservation, secondary postpartum hemorrhage, uterine embolization, uterine fibroids

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1191 Performance of Segmented Thermoelectric Materials Using 'Open-Short Circuit' Technique under Different Polarity

Authors: N. H. S. Mustafa, N. M. Yatim

Abstract:

Thermoelectric materials arrange in segmented design could increase the conversion of heat to electricity performance. This is due to the properties of materials that perform peak at narrow temperature range. Performance of the materials determines by dimensionless figure-of-merit, ZT which consist of thermoelectric properties namely Seebeck coefficient, electrical resistivity, and thermal conductivity. Since different materials were arrange in segmented, determination of ZT cannot be measured using the conventional approach. Therefore, this research used 'open-short circuit' technique to measure the segmented performance. Segmented thermoelectric materials consist of bismuth telluride, and lead telluride was segmented together under cold press technique. The results show thermoelectric properties measured is comparable with calculated based on commercially available of individual material. Performances of segmented sample under different polarity also indicate dependability of material with position and temperature. Segmented materials successfully measured under real condition and optimization of the segmented can be designed from the study of polarity change.

Keywords: thermoelectric, segmented, ZT, polarity, performance

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1190 The Impact of Cooperative Learning on Numerical Methods Course

Authors: Sara Bilal, Abdi Omar Shuriye, Raihan Othman

Abstract:

Numerical Methods is a course that can be conducted using workshops and group discussion. This study has been implemented on undergraduate students of level two at the Faculty of Engineering, International Islamic University Malaysia. The Numerical Method course has been delivered to two Sections 1 and 2 with 44 and 22 students in each section, respectively. Systematic steps have been followed to apply the student centered learning approach in teaching Numerical Method course. Initially, the instructor has chosen the topic which was Euler’s Method to solve Ordinary Differential Equations (ODE) to be learned. The students were then divided into groups with five members in each group. Initial instructions have been given to the group members to prepare their subtopics before meeting members from other groups to discuss the subtopics in an expert group inside the classroom. For the time assigned for the classroom discussion, the setting of the classroom was rearranged to accommodate the student centered learning approach. Teacher strength was by monitoring the process of learning inside and outside the class. The students have been assessed during the migrating to the expert groups, recording of a video explanation outside the classroom and during the final examination. Euler’s Method to solve the ODE was set as part of Question 3(b) in the final exam. It is observed that none of the students from both sections obtained a zero grade in Q3(b), compared to Q3(a) and Q3(c). Also, for Section 1(44 students), 29 students obtained the full mark of 7/7, while only 10 obtained 7/7 for Q3(a) and no students obtained 6/6 for Q3(c). Finally, we can recommend that the Numerical Method course be moved toward more student-centered Learning classrooms where the students will be engaged in group discussion rather than having a teacher one man show.

Keywords: teacher centered learning, student centered learning, mathematic, numerical methods

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1189 High Efficiency Achievement by a New Heterojunction N-Zno:Al/P-Si Solar Cell

Authors: A. Bouloufa, F. Khaled, K. Djessas

Abstract:

This paper presents a new structure of solar cell based on p-type microcrystalline silicon as an absorber and n-type aluminum doped zinc oxide (ZnO:Al) transparent conductive oxide as an optical window. The ZnO:Al layer deposited by rf-magnetron sputtering at room temperature yields a low resistivity about 7,64.10-2Ω.cm and more than 85% mean optical transmittance in the VIS–NIR range, with an optical band gap of 3.3 eV. These excellent optical properties of this layer in combination with an optimal contact at the front surface result in a superior light trapping yielding to efficiencies about 20%. In order to improve efficiency, we have used a p+-µc-Si thin layer highly doped as a back surface field which minimizes significantly the impact of rear surface recombination velocity on voltage and current leading to a high efficiency of 24%. Optoelectronic parameters were determined using the current density-voltage (J-V) curve by means of a numerical simulation with Analysis of Microelectronic and Photonic Structures (AMPS-1D) device simulator.

Keywords: optical window, thin film, solar cell, efficiency

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1188 Finite Element Study of Coke Shape Deep Beam to Column Moment Connection Subjected to Cyclic Loading

Authors: Robel Wondimu Alemayehu, Sihwa Jung, Manwoo Park, Young K. Ju

Abstract:

Following the aftermath of the 1994 Northridge earthquake, intensive research on beam to column connections is conducted, leading to the current design basis. The current design codes require the use of either a prequalified connection or a connection that passes the requirements of large-scale cyclic qualification test prior to use in intermediate or special moment frames. The second alternative is expensive both in terms of money and time. On the other hand, the maximum beam depth in most of the prequalified connections is limited to 900mm due to the reduced rotation capacity of deeper beams. However, for long span beams the need to use deeper beams may arise. In this study, a beam to column connection detail suitable for deep beams is presented. The connection detail comprises of thicker-tapered beam flange adjacent to the beam to column connection. Within the thicker-tapered flange region, two reduced beam sections are provided with the objective of forming two plastic hinges within the tapered-thicker flange region. In addition, the length, width, and thickness of the tapered-thicker flange region are proportioned in such a way that a third plastic hinge forms at the end of the tapered-thicker flange region. As a result, the total rotation demand is distributed over three plastic zones. Making it suitable for deeper beams that have lower rotation capacity at one plastic hinge. The effectiveness of this connection detail is studied through finite element analysis. For the study, a beam that has a depth of 1200mm is used. Additionally, comparison with welded unreinforced flange-welded web (WUF-W) moment connection and reduced beam section moment connection is made. The results show that the rotation capacity of a WUF-W moment connection is increased from 2.0% to 2.2% by applying the proposed moment connection detail. Furthermore, the maximum moment capacity, energy dissipation capacity and stiffness of the WUF-W moment connection is increased up to 58%, 49%, and 32% respectively. In contrast, applying the reduced beam section detail to the same WUF-W moment connection reduced the rotation capacity from 2.0% to 1.50% plus the maximum moment capacity and stiffness of the connection is reduced by 22% and 6% respectively. The proposed connection develops three plastic hinge regions as intended and it shows improved performance compared to both WUF-W moment connection and reduced beam section moment connection. Moreover, the achieved rotation capacity satisfies the minimum required for use in intermediate moment frames.

Keywords: connections, finite element analysis, seismic design, steel intermediate moment frame

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1187 Influences of Separation of the Boundary Layer in the Reservoir Pressure in the Shock Tube

Authors: Bruno Coelho Lima, Joao F.A. Martos, Paulo G. P. Toro, Israel S. Rego

Abstract:

The shock tube is a ground-facility widely used in aerospace and aeronautics science and technology for studies on gas dynamic and chemical-physical processes in gases at high-temperature, explosions and dynamic calibration of pressure sensors. A shock tube in its simplest form is comprised of two separate tubes of equal cross-section by a diaphragm. The diaphragm function is to separate the two reservoirs at different pressures. The reservoir containing high pressure is called the Driver, the low pressure reservoir is called Driven. When the diaphragm is broken by pressure difference, a normal shock wave and non-stationary (named Incident Shock Wave) will be formed in the same place of diaphragm and will get around toward the closed end of Driven. When this shock wave reaches the closer end of the Driven section will be completely reflected. Now, the shock wave will interact with the boundary layer that was created by the induced flow by incident shock wave passage. The interaction between boundary layer and shock wave force the separation of the boundary layer. The aim of this paper is to make an analysis of influences of separation of the boundary layer in the reservoir pressure in the shock tube. A comparison among CDF (Computational Fluids Dynamics), experiments test and analytical analysis were performed. For the analytical analysis, some routines in Python was created, in the numerical simulations (Computational Fluids Dynamics) was used the Ansys Fluent, and the experimental tests were used T1 shock tube located in IEAv (Institute of Advanced Studies).

Keywords: boundary layer separation, moving shock wave, shock tube, transient simulation

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1186 Rethinking the Constitutionality of Statutes: Rights-Compliant Interpretation in India and the UK

Authors: Chintan Chandrachud

Abstract:

When primary legislation is challenged for breaching fundamental rights, many courts around the world adopt interpretive techniques to avoid finding such legislation incompatible or invalid. In the UK, these techniques find sanction in section 3 of the Human Rights Act 1998, which directs courts to interpret legislation in a manner which is compatible with European Convention rights, ‘so far as it is possible to do so’. In India, courts begin with the interpretive presumption that Parliament intended to comply with fundamental rights under the Constitution of 1949. In comparing rights-compliant interpretation of primary legislation under the Human Rights Act and the Indian Constitution, this paper makes two arguments. First, that in the absence of a section 3-type mandate, Indian courts have a smaller range of interpretive tools at their disposal in interpreting primary legislation in a way which complies with fundamental rights. For example, whereas British courts frequently read words into statutes, Indian courts consider this an inapposite interpretive technique. The second argument flows naturally from the first. Given that Indian courts have a smaller interpretive toolbox, one would imagine that ceteris paribus, Indian courts’ power to strike down legislation would be triggered earlier than the declaration of incompatibility is in the UK. However, this is not borne out in practice. Faced with primary legislation which appears to violate fundamental rights, Indian courts often reluctantly uphold the constitutionality of statutes (rather than striking them down), as opposed to British courts, which make declarations of incompatibility. The explanation for this seeming asymmetry hinges on the difference between the ‘strike down’ power and the declaration of incompatibility. Whereas the former results in the disapplication of a statute, the latter throws the ball back into Parliament’s court, if only formally.

Keywords: constitutional law, judicial review, constitution of India, UK Human Rights Act

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1185 The Use of Surveys to Combat Fake News in Media Literacy Education

Authors: Jaejun Jong

Abstract:

Fake news has recently become a serious international problem. Therefore, researchers and policymakers worldwide have sought to understand fake news and develop strategies to combat it. This study consists of two primary parts: (1) a literature review of how surveys were used to understand fake news and identify problems caused by fake news, and (2) a discussion of how surveys were used to fight back against fake news in educational settings. This second section specifically analyzes surveys used to evaluate a South Korean elementary school program designed to improve students’ metacognition and critical thinking. This section seeks to identify potential problems that may occur in the elementary school setting. The literature review shows that surveys can help people to understand fake news based on its traits rather than its definition due to the lack of agreement on the definition of fake news. The literature review also shows that people are not good at identifying fake news or evaluating their own ability to identify fake news; indeed, they are more likely to share information that aligns with their previous beliefs. In addition, the elementary school survey data shows that there may be substantial errors in the program evaluation process, likely caused by processing errors or the survey procedure, though the exact cause is not specified. Such a significant error in evaluating the effects of the educational program prevents teachers from making proper decisions and accurately evaluating the program. Therefore, identifying the source of such errors would improve the overall quality of education, which would benefit both teachers and students.

Keywords: critical thinking, elementary education, program evaluation, survey

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1184 Elastoplastic Collapse Analysis of Pipe Bends Using Finite Element Analysis

Authors: Tawanda Mushiri, Charles Mbohwa

Abstract:

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

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

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1183 General Formula for Water Surface Profile over Side Weir in the Combined, Trapezoidal and Exponential, Channels

Authors: Abdulrahman Abdulrahman

Abstract:

A side weir is a hydraulic structure set into the side of a channel. This structure is used for water level control in channels, to divert flow from a main channel into a side channel when the water level in the main channel exceeds a specific limit and as storm overflows from urban sewerage system. Computation of water surface over the side weirs is essential to determine the flow rate of the side weir. Analytical solutions for water surface profile along rectangular side weir are available only for the special cases of rectangular and trapezoidal channels considering constant specific energy. In this paper, a rectangular side weir located in a combined (trapezoidal with exponential) channel was considered. Expanding binominal series of integer and fraction powers and the using of reduction formula of cosine function integrals, a general analytical formula was obtained for water surface profile along a side weir in a combined (trapezoidal with exponential) channel. Since triangular, rectangular, trapezoidal and parabolic cross-sections are special cases of the combined cross section, the derived formula, is applicable to triangular, rectangular, trapezoidal cross-sections as analytical solution and semi-analytical solution to parabolic cross-section with maximum relative error smaller than 0.76%. The proposed solution should be a useful engineering tool for the evaluation and design of side weirs in open channel.

Keywords: analytical solution, combined channel, exponential channel, side weirs, trapezoidal channel, water surface profile

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1182 Structural, Optical and Electrical Properties of Gd Doped ZnO Thin Films Prepared by a Sol-Gel Method

Authors: S. M. AL-Shomar, N. B. Ibrahim, Sahrim Hj. Ahmad

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ZnO thin films with various Gd doping concentration (0, 0.01, 0.03 and 0.05 mol/L) have been synthesized by sol–gel method on quartz substrates at annealing temperature of 600 ºC. X-ray analysis reveals that ZnO(Gd) films have hexagonal wurtzite structure. No peaks that correspond to Gd metal clusters or gadolinium acetylacetonate are detected in the patterns. The position of the main peak (101) shifts to higher angles after doping. The surface morphologies studied using a field emission scanning electron microscope (FESEM) showed that the grain size and the films thickness reduced gradually with the increment of Gd concentration. The roughness of ZnO film investigated by an atomic force microscopy (AFM) showed that the films are smooth and high dense grain. The roughness of doped films decreased from 6.05 to 4.84 rms with the increment of dopant concentration.The optical measurements using a UV-Vis-NIR spectroscopy showed that the Gd doped ZnO thin films have high transmittance (above 80%) in the visible range and the optical band gap increase with doping concentration from 3.13 to 3.39 eV. The doped films show low electrical resistivity 2.6 × 10-3Ω.cm.at high doping concentration.

Keywords: Gd doped ZnO, electric, optics, microstructure

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1181 Intellectual Property Rights (IPR) in the Relations among Nations: Towards a Renewed Hegemony or Not

Authors: Raju K. Thadikkaran

Abstract:

Introduction: The IPR have come to the centre stage of development discourse today for a variety of reasons: It ranges from the arbitrariness in the enforcement, overlapping and mismatch with various international agreements and conventions, divergence in the definition, nature and content and the duration as well as severe adverse consequences to technologically weak developing countries. In turn, the IPR have acquired prominence in the foreign policy making as well as in the relations among nations. Quite naturally, there is ample scope for an examination of the correlation between Technology, IPR and International Relations in the contemporary world. Nature and Scope: A cursory examination of the realm of IPR and its protection shall reveals the acute divergence that exists in the perspectives, on all matters related to the very definition, nature, content, scope and duration. The proponents of stronger protection, mostly technologically advanced countries, insist on a stringent IP Regime whereas technologically weak developing countries seem to advocate for flexibilities. From the perspective of developing countries like India, one of the most crucial concerns is related to the patenting of life forms and the protection of TK and BD. There have been several instances of Bio-piracy and Bio-prospecting of the resources related to BD and TK from the Bio-rich Global South. It is widely argued that many provisions in the TRIPS are capable of offsetting the welcome provisions in the CBD such as the Access and Benefit Sharing and Prior Informed Consent. The point that is being argued out is as to how the mismatch between the provisions in the TRIPS Agreement and the CBD could be addressed in a healthy manner so that the essential minimum legitimate interests of all stakeholders could be secured thereby introducing a new direction to the international relations. The findings of this study reveal that the challenges roused by the TRIPS Regime over-weigh the opportunities. The mismatch in the provisions in this regard has generated various crucial issues such as Bio-piracy and Bio-prospecting. However, there is ample scope for managing and protecting IP through institutional innovation, legislative, executive and administrative initiative at the global, national and regional levels. The Indian experience is quite reflective of the same and efforts are being made through the new national IPR policy. This paper, employing Historical Analytical Method, has Three Sections. The First Section shall trace the correlation between the Technology, IPR and international relations. The Second Section shall review the issues and potential concerns in the protection and management of IP related to the BD and TK in the developing countries in the wake of the TRIPS and the CBD. The Final Section shall analyze the Indian Experience in this regard and the experience of the bio-rich Kerala in particular.

Keywords: IPR, technology and international relations, bio-diversity, traditional knowledge

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1180 Determines the Continuity of Void in Underground Mine Tunnel Using Ground Penetrating Radar

Authors: Farid Adisaputra Gumilang

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Kucing Liar Underground Mine is a future mine of PT Freeport Indonesia PTFI that is currently being developed. In the development process, problems were found when blasting the tunnels; there were overbreak, and void occur caused by geological contact or poor rock conditions. Geotechnical engineers must evaluate not only the remnant capacity of ground support systems but also investigate the depth of rock mass yield within pillars. To prevent the potential hazard caused by void zones, geotechnical engineers must ensure the planned drift is mined in the best location where people can work safely. GPR, or Ground penetrating radar, is a geophysical method that can image the subsurface. This non-destructive method uses electromagnetic radiation and detects the reflected signals from subsurface structures. The GPR survey measurements are conducted 48 meters along the drift that has a poor ground condition with 150MHz antenna with several angles (roof, wall, and floor). Concern grounds are determined by the continuity of reflector/low reflector in the radargram section. Concern grounds are determined by the continuity of reflector/low reflector in the radargram section. In this paper, processing data using instantaneous amplitude to identify the void zone. In order to have a good interpretation and result, it combines with the geological information and borehole camera data, so the calibrated GPR data allows the geotechnical engineer to determine the safe location to change the drift location.

Keywords: underground mine, ground penetrating radar, reflectivity, borehole camera

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1179 A Battle of Identity(ies): Deconstructing Spaces of Belonging in Saleem Haddad’s Guapa and Hasan Namir’s God in Pink

Authors: Nour Aladdin

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This paper explores the interconnectedness of belonging, space, and identity in Anglo Arab literature, particularly Saleem Haddad’s Guapa and Hasan Namir’sGod in Pink. This paper suggest that Rasa and Ramy, the queer Arab characters respectively, do not belong in either the Middle East or the West. Using Amin Maalouf’s analysis of the Arab identity, specifically his argument that an individual identifies strongly with the aspect of their identity that is under attack, this paper argues that all of Rasa and Ramy’s spaces are politically charged - a term that denotes that all values and beliefs instilled in Arabs and their spaces are heavily influenced by Arab politics, culture, and, often times religion. Therefore, the politically charged environments Rasa and Ramy inhabit will always be against one part of their identity, which is why they cannot identify as queer and Arab simultaneously. For Rasa, the unnamed Middle Eastern country, his home environment, as well as the so-called safe space nightclub, condemn his queerness, leading him to connect more to his sexual orientation. However, Rasa associates himself with his Arab roots when he migrates to America, a different form of politically charged space that minoritizes his ethnicity. Similarly, Ramy’s spaces are naturally religiopolitical after Islam heightened in Iraq during the Iraq War; as a result, Ramy’s home environment, Sheikh Ammar’s house, the mosque, and the nightclub are influenced by the religiopolitics and bombard his ability to identify as not only a queer Arab but a queer Arab Muslim. Ultimately, because Rasa and Ramy are constantly in movement, their identity attributes are also in movement. This paper is divided into three sections. The first section focuses on Guapa and the Arab Spring’s politics, mainly its influence on queer Arabs in and around the Middle East. Drawing from a number of queer and Arab gender theories, I analyze all of Rasa’s spaces as politically charged that prevent him from the means to be queer and Arab. The second section examines God in Pink in close connection to the 2003 invasion of Iraq. Ramy’s spaces are religiopolitically charged, that prevent him to embrace all of his identity attributes – nationality, ethnicity, sexual orientation, and religious affiliation – concomitantly. The last section considers the rapid use of technology and social media in the Middle East as a means to provide deviant heterotopic spaces for queer Arabs. With the rise of subtle and covert queer heterotopias, there is a slow and steady shift of queer tolerance in the Arab world.

Keywords: belonging, identity, spaces, queer, arabness, middle east, orientalism

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1178 Preparation and Properties of PP/EPDM Reinforced with Graphene

Authors: M. Haghnegahdar, G. Naderi, M. H. R. Ghoreishy

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Polypropylene(PP)/Ethylene Propylene Diene Monomer (EPDM) samples (80/20) containing 0, 0.5, 1, 1.5, 2, 2.5, and 3 (expressed in mass fraction) graphene were prepared using melt compounding method to investigate microstructure, mechanical properties, and thermal stability as well as electrical resistance of samples. X-Ray diffraction data confirmed that graphene platelets are well dispersed in PP/EPDM. Mechanical properties such as tensile strength, impact strength and hardness demonstrated increasing trend by graphene loading which exemplifies substantial reinforcing nature of this kind of nano filler and it's good interaction with polymer chains. At the same time it is found that thermo-oxidative degradation of PP/EPDM nanocomposites is noticeably retarded with the increasing of graphene content. Electrical surface resistivity of the nanocomposite was dramatically changed by forming electrical percolation threshold and leads to change electrical behavior from insulator to semiconductor. Furthermore, these results were confirmed by scanning electron microscopy(SEM), dynamic mechanical thermal analysis (DMTA), and transmission electron microscopy (TEM).

Keywords: nanocomposite, graphene, microstructure, mechanical properties

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1177 Litigating Innocence in the Era of Forensic Law: The Problem of Wrongful Convictions in the Absence of Effective Post-Conviction Remedies in South Africa

Authors: Tapiwa Shumba

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The right to fairness and access to appeals and reviews enshrined under the South African Constitution seeks to ensure that justice is served. In essence, the constitution and the law have put in place mechanisms to ensure that a miscarriage of justice through wrongful convictions does not occur. However, once convicted and sentenced on appeal the procedural safeguards seem to resign as if to say, the accused has met his fate. The challenge with this construction is that even within an ideally perfect legal system wrongful convictions would still occur. Therefore, it is not so much of the failings of a legal system that demand attention but mechanisms to redress the results of such failings where evidence becomes available that a wrongful conviction occurred. In this context, this paper looks at the South African criminal procedural mechanisms for litigating innocence post-conviction. The discussion focuses on the role of section 327 of the South African Criminal Procedure Act and its apparent shortcomings in providing an avenue for victims of miscarriages to litigate their innocence by adducing new evidence at any stage during their wrongful incarceration. By looking at developments in other jurisdiction such as the United Kingdom, where South African criminal procedure draws much of its history, and the North Carolina example which in itself was inspired by the UK Criminal Cases Review Commission, this paper is able to make comparisons and draw invaluable lessons for the South African criminal justice system. Lessons from these foreign jurisdictions show that South African post-conviction criminal procedures need reform in line with constitutional values of human dignity, equality before the law, openness and transparency. The paper proposes an independent review of the current processes to assess the current post-conviction procedures under section 327. The review must look into the effectiveness of the current system and how it can be improved in line with new substantive legal provisions creating access to DNA evidence for post-conviction exonerations. Although the UK CCRC body should not be slavishly followed, its operations and the process leading to its establishment certainly provide a good point of reference and invaluable lessons for the South African criminal justice system seeing that South African law on this aspect has generally followed the English approach except that current provisions under section 327 are a mirror of the discredited system of the UK’s previous dispensation. A new independent mechanism that treats innocent victims of the criminal justice system with dignity away from the current political process is proposed to enable the South African criminal justice to benefit fully from recent and upcoming advances in science and technology.

Keywords: innocence, forensic law, post-conviction remedies, South African criminal justice system, wrongful conviction

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1176 Anatomical Adaptations of Three Astragalus Species under Salt Stress

Authors: Faycal Boughalleb, Raoudha Abdellaoui

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The effect of NaCl stress on root and leaf anatomy was investigated in three Astragalus species grown in 0-300 mM NaCl for 30 days under greenhouse conditions. Root cross section and cortex thickness was reduced under salt stress in both species while A. tenuifolius showed thinner cortex and the root cross section was unchanged. The epidermis stele thickness was unaffected by salinity in A. armatus and A. tenuifolius and was reduced in A. mareoticus with smaller xylem vessel size. In addition, vessel density and wall thickness of xylem was increased under salt conditions in the studies species. The entire lamina and mesophyll of the three species were thinner in salt-stressed plants. A. armatus and A. tenuifolius showed the higher thickness with increased size of the lower epidermis. NaCl (300 mM) reduced leaf water content by 41.5 % in A. mareoticus while it was unchanged in the other species. The size of the vascular bundle increased under salinity in A. tenuifolius leaves and it was unchanged in the other ones. A longer distance between leaf vascular bundle was occurred in A. mareoticus. The effects of NaCl on root and leaf ultrastructure are discussed in relation to the degree of salt resistance of these species. The unchanged biomass production under salt stress confirmed the higher tolerance oft A. tenuifolius to salinity. A. armatus was moderately salt tolerant with decrease of biomass production by 14.2 % while A. mareoticus was considered as salt sensitive plant when the decrease in biomass production reached 56.8%.

Keywords: Astragalus species, leaf ultrastructure, root anatomy, salt stress

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1175 Educational Tours as a Learning Tool to the Third Years Tourism Students of De La Salle University, Dasmarinas

Authors: Jackqueline Uy, Hannah Miriam Verano, Crysler Luis Verbo, Irene Gueco

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Educational tours are part of the curriculum of the College of Tourism and Hospitality Management, De La Salle University-Dasmarinas. They are highly significant to the students, especially Tourism students. The purpose of this study was to determine how effective educational tours were as a learning tool using the Experiential Learning Theory by David Kolb. This study determined the demographic profile of the third year tourism students in terms of gender, section, educational tours joined, and monthly family income and lastly, this study determined if there is a significant difference between the demographic profile of the respondents and their assessment of educational tours as a learning tool. The researchers used a historical research design with the third-year students of the bachelor of science in tourism management as the population size and used a random sampling method. The researchers made a survey questionnaire and utilized statistical tools such as weighted mean, frequency distribution, percentage, standard deviation, T-test, and ANOVA. The result of the study answered the profile of the respondents such as the gender, section, educational tour/s joined, and family monthly income. The findings of the study showed that the 3rd year tourism management students strongly agree that educational tours are a highly effective learning tool in terms of active experimentation, concrete experience, reflective observation, and abstract conceptualisation based on the data gathered from the respondents.

Keywords: CTHM, educational tours, experiential learning theory, De La Salle University Dasmarinas, tourism

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1174 Investigation of Elastic Properties of 3D Full Five Directional (f5d) Braided Composite Materials

Authors: Apeng Dong, Shu Li, Wenguo Zhu, Ming Qi, Qiuyi Xu

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The primary objective of this paper is to focus on the elasticity properties of three-dimensional full five directional (3Df5d) braided composite. A large body of research has been focused on the 3D four directional (4d) and 3D five directional (5d) structure but not much research on the 3Df5d material. Generally, the influence of the yarn shape on mechanical properties of braided materials tends to be ignored, which makes results too ideal. Besides, with the improvement of the computational ability, people are accustomed to using computers to predict the material parameters, which fails to give an explicit and concise result facilitating production and application. Based on the traditional mechanics, this paper firstly deduced the functional relation between elasticity properties and braiding parameters. In addition, considering the actual shape of yarns after consolidation, the longitudinal modulus is modified and defined practically. Firstly, the analytic model is established based on the certain assumptions for the sake of clarity, this paper assumes that: A: the cross section of axial yarns is square; B: The cross section of braiding yarns is hexagonal; C: the characters of braiding yarns and axial yarns are the same; D: The angle between the structure boundary and the projection of braiding yarns in transverse plane is 45°; E: The filling factor ε of composite yarns is π/4; F: The deformation of unit cell is under constant strain condition. Then, the functional relation between material constants and braiding parameters is systematically deduced aimed at the yarn deformation mode. Finally, considering the actual shape of axial yarns after consolidation, the concept of technology factor is proposed and the longitudinal modulus of the material is modified based on the energy theory. In this paper, the analytic solution of material parameters is given for the first time, which provides a good reference for further research and application for 3Df5d materials. Although the analysis model is established based on certain assumptions, the analysis method is also applicable for other braided structures. Meanwhile, it is crucial that the cross section shape and straightness of axial yarns play dominant roles in the longitudinal elastic property. So in the braiding and solidifying process, the stability of the axial yarns should be guaranteed to increase the technology factor to reduce the dispersion of material parameters. Overall, the elastic properties of this materials are closely related to the braiding parameters and can be strongly designable, and although the longitudinal modulus of the material is greatly influenced by the technology factors, it can be defined to certain extent.

Keywords: analytic solution, braided composites, elasticity properties, technology factor

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1173 Radar Cross Section Modelling of Lossy Dielectrics

Authors: Ciara Pienaar, J. W. Odendaal, J. Joubert, J. C. Smit

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Radar cross section (RCS) of dielectric objects play an important role in many applications, such as low observability technology development, drone detection, and monitoring as well as coastal surveillance. Various materials are used to construct the targets of interest such as metal, wood, composite materials, radar absorbent materials, and other dielectrics. Since simulated datasets are increasingly being used to supplement infield measurements, as it is more cost effective and a larger variety of targets can be simulated, it is important to have a high level of confidence in the predicted results. Confidence can be attained through validation. Various computational electromagnetic (CEM) methods are capable of predicting the RCS of dielectric targets. This study will extend previous studies by validating full-wave and asymptotic RCS simulations of dielectric targets with measured data. The paper will provide measured RCS data of a number of canonical dielectric targets exhibiting different material properties. As stated previously, these measurements are used to validate numerous CEM methods. The dielectric properties are accurately characterized to reduce the uncertainties in the simulations. Finally, an analysis of the sensitivity of oblique and normal incidence scattering predictions to material characteristics is also presented. In this paper, the ability of several CEM methods, including method of moments (MoM), and physical optics (PO), to calculate the RCS of dielectrics were validated with measured data. A few dielectrics, exhibiting different material properties, were selected and several canonical targets, such as flat plates and cylinders, were manufactured. The RCS of these dielectric targets were measured in a compact range at the University of Pretoria, South Africa, over a frequency range of 2 to 18 GHz and a 360° azimuth angle sweep. This study also investigated the effect of slight variations in the material properties on the calculated RCS results, by varying the material properties within a realistic tolerance range and comparing the calculated RCS results. Interesting measured and simulated results have been obtained. Large discrepancies were observed between the different methods as well as the measured data. It was also observed that the accuracy of the RCS data of the dielectrics can be frequency and angle dependent. The simulated RCS for some of these materials also exhibit high sensitivity to variations in the material properties. Comparison graphs between the measured and simulation RCS datasets will be presented and the validation thereof will be discussed. Finally, the effect that small tolerances in the material properties have on the calculated RCS results will be shown. Thus the importance of accurate dielectric material properties for validation purposes will be discussed.

Keywords: asymptotic, CEM, dielectric scattering, full-wave, measurements, radar cross section, validation

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1172 Vibration Analysis of Stepped Nanoarches with Defects

Authors: Jaan Lellep, Shahid Mubasshar

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A numerical solution is developed for simply supported nanoarches based on the non-local theory of elasticity. The nanoarch under consideration has a step-wise variable cross-section and is weakened by crack-like defects. It is assumed that the cracks are stationary and the mechanical behaviour of the nanoarch can be modeled by Eringen’s non-local theory of elasticity. The physical and thermal properties are sensitive with respect to changes of dimensions in the nano level. The classical theory of elasticity is unable to describe such changes in material properties. This is because, during the development of the classical theory of elasticity, the speculation of molecular objects was avoided. Therefore, the non-local theory of elasticity is applied to study the vibration of nanostructures and it has been accepted by many researchers. In the non-local theory of elasticity, it is assumed that the stress state of the body at a given point depends on the stress state of each point of the structure. However, within the classical theory of elasticity, the stress state of the body depends only on the given point. The system of main equations consists of equilibrium equations, geometrical relations and constitutive equations with boundary and intermediate conditions. The system of equations is solved by using the method of separation of variables. Consequently, the governing differential equations are converted into a system of algebraic equations whose solution exists if the determinant of the coefficients of the matrix vanishes. The influence of cracks and steps on the natural vibration of the nanoarches is prescribed with the aid of additional local compliance at the weakened cross-section. An algorithm to determine the eigenfrequencies of the nanoarches is developed with the help of computer software. The effects of various physical and geometrical parameters are recorded and drawn graphically.

Keywords: crack, nanoarches, natural frequency, step

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1171 Lateral Torsional Buckling Investigation on Welded Q460GJ Structural Steel Unrestrained Beams under a Point Load

Authors: Yue Zhang, Bo Yang, Gang Xiong, Mohamed Elchalakanic, Shidong Nie

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This study aims to investigate the lateral torsional buckling of I-shaped cross-section beams fabricated from Q460GJ structural steel plates. Both experimental and numerical simulation results are presented in this paper. A total of eight specimens were tested under a three-point bending, and the corresponding numerical models were established to conduct parametric studies. The effects of some key parameters such as the non-dimensional member slenderness and the height-to-width ratio, were investigated based on the verified numerical models. Also, the results obtained from the parametric studies were compared with the predictions calculated by different design codes including the Chinese design code (GB50017-2003, 2003), the new draft version of Chinese design code (GB50017-201X, 2012), Eurocode 3 (EC3, 2005) and the North America design code (ANSI/AISC360-10, 2010). These comparisons indicated that the sectional height-to-width ratio does not play an important role to influence the overall stability load-carrying capacity of Q460GJ structural steel beams with welded I-shaped cross-sections. It was also found that the design methods in GB50017-2003 and ANSI/AISC360-10 overestimate the overall stability and load-carrying capacity of Q460GJ welded I-shaped cross-section beams.

Keywords: experimental study, finite element analysis, global stability, lateral torsional buckling, Q460GJ structural steel

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1170 Chance One’s Arm: Critical Evaluation on Laws of Sports Gambling in India

Authors: Archen Sara Vincent

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Gambling is the practice or act of betting or wagering on uncertain events with the hope of winning money or any other valuable assets. Nowadays, the practice of gambling can be seen in almost all grounds of events, especially in sports. In sports, this is commonly known among people as sports betting. The history of gambling can be traced about 2,000 years back. It originated from Greeks, from Greeks to the Romans, then to England, where betting on horse races was much popular among the elites. The evolution of gambling in sports has made a greater impact in the modern era. In India, the legality of gambling in sports is regulated by The Public Gambling Act 1867, which prohibits gambling activities in public places. The major draw of this statute is that it does not have specific laws regarding online sports gambling. Section 30 of The Indian Contract Act 1872 considers wagering agreements void. However, there are certain exceptions for this section, that is, (1) state-owned lotteries and (2) wagering on horse races with a sum of Rupees 500 or upward. As per the Indian Constitution, the rules regarding sports gambling are within the powers of the state legislatures. Some of the states have enacted their own laws which explicitly permit or prohibit gambling within their jurisdiction. Recently in Tamilnadu, The Tamilnadu Gaming Act was amended in 2021 to completely ban online gambling and betting. Moreover, the Central Government has introduced the Online Gaming and Prevention of Fraud Bill, 2018, to legalize and regulate sports betting in India. However, this bill has not yet been passed as law. Now as the Indian legal system does not have a specific rule regarding online sports gambling, sports betting companies use this major drawback and attract people to use the gambling and betting apps by advertising with well-known sports players and other celebrities. This paper aims to critically evaluate gambling in sports and the laws relating to it in India.

Keywords: history of gambling, The Public Gambling Act 1862, state legislations, gambling in India

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1169 Kou Jump Diffusion Model: An Application to the SP 500; Nasdaq 100 and Russell 2000 Index Options

Authors: Wajih Abbassi, Zouhaier Ben Khelifa

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The present research points towards the empirical validation of three options valuation models, the ad-hoc Black-Scholes model as proposed by Berkowitz (2001), the constant elasticity of variance model of Cox and Ross (1976) and the Kou jump-diffusion model (2002). Our empirical analysis has been conducted on a sample of 26,974 options written on three indexes, the S&P 500, Nasdaq 100 and the Russell 2000 that were negotiated during the year 2007 just before the sub-prime crisis. We start by presenting the theoretical foundations of the models of interest. Then we use the technique of trust-region-reflective algorithm to estimate the structural parameters of these models from cross-section of option prices. The empirical analysis shows the superiority of the Kou jump-diffusion model. This superiority arises from the ability of this model to portray the behavior of market participants and to be closest to the true distribution that characterizes the evolution of these indices. Indeed the double-exponential distribution covers three interesting properties that are: the leptokurtic feature, the memory less property and the psychological aspect of market participants. Numerous empirical studies have shown that markets tend to have both overreaction and under reaction over good and bad news respectively. Despite of these advantages there are not many empirical studies based on this model partly because probability distribution and option valuation formula are rather complicated. This paper is the first to have used the technique of nonlinear curve-fitting through the trust-region-reflective algorithm and cross-section options to estimate the structural parameters of the Kou jump-diffusion model.

Keywords: jump-diffusion process, Kou model, Leptokurtic feature, trust-region-reflective algorithm, US index options

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