Search results for: conditional proportional reversed hazard rate model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 23517

Search results for: conditional proportional reversed hazard rate model

3207 The Impact of Deprivation on the Prevalence of Common Mental Health Disorders in Clinical Commissioning Groups across England: A Retrospective, Cross-Sectional Study

Authors: Mohammed-Hareef Asunramu, Sana Hashemi, Raja Ohri, Luc Worthington, Nadia Zaman, Junkai Zhu

Abstract:

Background: The 2012 Health and Social Care Act committed to a ‘parity of esteem between mental and physical health services. Although this investment, aimed to both increase the quality of services and ensure the retention of mental health staff, questions remained regarding its ability to prevent mental health problems. One possible solution is a focus on the social determinants of health which have been shown to impact mental health. Aim: To examine the relationship between the index of multiple deprivations (IMD) and the prevalence of common mental health disorders (CMD) for CCGs in NHS England between 2019 and 2020. Design and setting: Cross-sectional analysis of 189 CCGs in NHS England. Methods: A multivariate linear regression model was utilized with CMD as outcome variable and IMD, age and ethnicity as explanatory variables. Datasets were obtained from Public Health England and the latest UK Census. Results: CCG IMD was found to have a significantly positive relationship with CMD. For every 1-point increase in IMD, CMD increases by 0.25%. Ethnicity had a significantly positive relationship with CMD. For every 1% increase in the population that identifies as BME, there is a 0.03% increase in CMD. Age had a significantly negative relationship with CMD. For every 1% increase in the population aged 60+, there is a 0.11% decrease in CMD. Conclusion: This study demonstrates that addressing mental health issues may require a multi-pronged approach. Beyond budget increases, it is essential to prioritize health equity, with careful considerations towards ethnic minorities and different age brackets.

Keywords: deprivation, health inequality, mental health, social determinants

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3206 Empirical Analyses of Students’ Self-Concepts and Their Mathematics Achievements

Authors: Adetunji Abiola Olaoye

Abstract:

The study examined the students’ self-concepts and mathematics achievement viz-a-viz the existing three theoretical models: Humanist self-concept (M1), Contemporary self-concept (M2) and Skills development self-concept (M3). As a qualitative research study, it comprised of one research question, which was transformed into hypothesis viz-a-viz the existing theoretical models. Sample to the study comprised of twelve public secondary schools from which twenty-five mathematics teachers, twelve counselling officers and one thousand students of Upper Basic II were selected based on intact class as school administrations and system did not allow for randomization. Two instruments namely 10 items ‘Achievement test in Mathematics’ (r1=0.81) and 10 items Student’s self-concept questionnaire (r2=0.75) were adapted, validated and used for the study. Data were analysed through descriptive, one way ANOVA, t-test and correlation statistics at 5% level of significance. Finding revealed mean and standard deviation of pre-achievement test scores of (51.322, 16.10), (54.461, 17.85) and (56.451, 18.22) for the Humanist Self-Concept, Contemporary Self-Concept and Skill Development Self-Concept respectively. Apart from that study showed that there was significant different in the academic performance of students along the existing models (F-cal>F-value, df = (2,997); P<0.05). Furthermore, study revealed students’ achievement in mathematics and self-concept questionnaire with the mean and standard deviation of (57.4, 11.35) and (81.6, 16.49) respectively. Result confirmed an affirmative relationship with the Contemporary Self-Concept model that expressed an individual subject and specific self-concept as the primary determinants of higher academic achievement in the subject as there is a statistical correlation between students’ self-concept and mathematics achievement viz-a-viz the existing three theoretical models of Contemporary (M2) with -Z_cal<-Z_val, df=998: P<0.05*. The implication of the study was discussed with recommendations and suggestion for further studies proffered.

Keywords: contemporary, humanists, self-concepts, skill development

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3205 Extracting the Coupled Dynamics in Thin-Walled Beams from Numerical Data Bases

Authors: Mohammad A. Bani-Khaled

Abstract:

In this work we use the Discrete Proper Orthogonal Decomposition transform to characterize the properties of coupled dynamics in thin-walled beams by exploiting numerical simulations obtained from finite element simulations. The outcomes of the will improve our understanding of the linear and nonlinear coupled behavior of thin-walled beams structures. Thin-walled beams have widespread usage in modern engineering application in both large scale structures (aeronautical structures), as well as in nano-structures (nano-tubes). Therefore, detailed knowledge in regard to the properties of coupled vibrations and buckling in these structures are of great interest in the research community. Due to the geometric complexity in the overall structure and in particular in the cross-sections it is necessary to involve computational mechanics to numerically simulate the dynamics. In using numerical computational techniques, it is not necessary to over simplify a model in order to solve the equations of motions. Computational dynamics methods produce databases of controlled resolution in time and space. These numerical databases contain information on the properties of the coupled dynamics. In order to extract the system dynamic properties and strength of coupling among the various fields of the motion, processing techniques are required. Time- Proper Orthogonal Decomposition transform is a powerful tool for processing databases for the dynamics. It will be used to study the coupled dynamics of thin-walled basic structures. These structures are ideal to form a basis for a systematic study of coupled dynamics in structures of complex geometry.

Keywords: coupled dynamics, geometric complexity, proper orthogonal decomposition (POD), thin walled beams

Procedia PDF Downloads 407
3204 Spatial Planning Model on Landslide Risk Disaster at West Java Geothermal Field, Indonesia

Authors: Herawanti Kumalasari, Raldi Hendro Koestoer, Hayati Sari Hasibuan

Abstract:

Geographically, Indonesia is located in the arc of volcanoes that cause disaster prone one of them is landslide disaster. One of the causes of the landslide is the conversion of land from forest to agricultural land in upland areas and river border that has a steep slope. The study area is located in the highlands with fertile soil conditions, so most of the land is used as agricultural land and plantations. Land use transfer also occurs around the geothermal field in Pangalengan District, West Java Province which will threaten the sustainability of geothermal energy utilization and the safety of the community. The purpose of this research is to arrange the concept of spatial pattern arrangement in the geothermal area based on disaster mitigation. This research method using superimpose analysis. Superimpose analysis to know the basic physical condition of the planned area through the overlay of disaster risk map with the map of the plan of spatial plan pattern of Bandung Regency Spatial Plan. The results of the analysis will then be analyzed spatially. The results have shown that most of the study areas were at moderate risk level. Planning of spatial pattern of existing study area has not fully considering the spread of disaster risk that there are settlement area and the agricultural area which is in high landslide risk area. The concept of the arrangement of the spatial pattern of the study area will use zoning system which is divided into three zones namely core zone, buffer zone and development zone.

Keywords: spatial planning, geothermal, disaster risk, zoning

Procedia PDF Downloads 258
3203 A Controlled Natural Language Assisted Approach for the Design and Automated Processing of Service Level Agreements

Authors: Christopher Schwarz, Katrin Riegler, Erwin Zinser

Abstract:

The management of outsourcing relationships between IT service providers and their customers proofs to be a critical issue that has to be stipulated by means of Service Level Agreements (SLAs). Since service requirements differ from customer to customer, SLA content and language structures vary largely, standardized SLA templates may not be used and an automated processing of SLA content is not possible. Hence, SLA management is usually a time-consuming and inefficient manual process. For overcoming these challenges, this paper presents an innovative and ITIL V3-conform approach for automated SLA design and management using controlled natural language in enterprise collaboration portals. The proposed novel concept is based on a self-developed controlled natural language that follows a subject-predicate-object approach to specify well-defined SLA content structures that act as templates for customized contracts and support automated SLA processing. The derived results eventually enable IT service providers to automate several SLA request, approval and negotiation processes by means of workflows and business rules within an enterprise collaboration portal. The illustrated prototypical realization gives evidence of the practical relevance in service-oriented scenarios as well as the high flexibility and adaptability of the presented model. Thus, the prototype enables the automated creation of well defined, customized SLA documents, providing a knowledge representation that is both human understandable and machine processable.

Keywords: automated processing, controlled natural language, knowledge representation, information technology outsourcing, service level management

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3202 Film Therapy on Adolescent Body Image: A Pilot Study

Authors: Sonia David, Uma Warrier

Abstract:

Background: Film therapy is the use of commercial or non-commercial films to enhance healing for therapeutic purposes. Objectives: The mixed-method study aims to evaluate the effect of film-based counseling on body image dissatisfaction among adolescents to precisely ascertain the cause of the alteration in body image dissatisfaction due to the said intervention. Method: The one group pre-test post-test research design study using inferential statistics and thematic analysis is based on a pre-test post-test design conducted on 44 school-going adolescents between 13 and 17. The Body Shape Questionnaire (BSQ- 34) was used as a pre-test and post-test measure. The film-based counseling intervention model was used through individual counseling sessions. The analysis involved paired sample t-test used to examine the data quantitatively, and thematic analysis was used to evaluate qualitative data. Findings: The results indicated that there is a significant difference between the pre-test and post-test means. Since t(44)= 9.042 is significant at a 99% confidence level, it is ascertained that film-based counseling intervention reduces body image dissatisfaction. The five distinct themes from the thematic analysis are “acceptance, awareness, empowered to change, empathy, and reflective.” Novelty: The paper originally contributes to the repertoire of research on film therapy as a successful counseling intervention for addressing the challenges of body image dissatisfaction. This study also opens avenues for considering alteration of teaching pedagogy to include video-based learning in various subjects.

Keywords: body image dissatisfaction, adolescents, film-based counselling, film therapy, acceptance and commitment therapy

Procedia PDF Downloads 270
3201 Modeling and Simulation of Ship Structures Using Finite Element Method

Authors: Javid Iqbal, Zhu Shifan

Abstract:

The development in the construction of unconventional ships and the implementation of lightweight materials have shown a large impulse towards finite element (FE) method, making it a general tool for ship design. This paper briefly presents the modeling and analysis techniques of ship structures using FE method for complex boundary conditions which are difficult to analyze by existing Ship Classification Societies rules. During operation, all ships experience complex loading conditions. These loads are general categories into thermal loads, linear static, dynamic and non-linear loads. General strength of the ship structure is analyzed using static FE analysis. FE method is also suitable to consider the local loads generated by ballast tanks and cargo in addition to hydrostatic and hydrodynamic loads. Vibration analysis of a ship structure and its components can be performed using FE method which helps in obtaining the dynamic stability of the ship. FE method has developed better techniques for calculation of natural frequencies and different mode shapes of ship structure to avoid resonance both globally and locally. There is a lot of development towards the ideal design in ship industry over the past few years for solving complex engineering problems by employing the data stored in the FE model. This paper provides an overview of ship modeling methodology for FE analysis and its general application. Historical background, the basic concept of FE, advantages, and disadvantages of FE analysis are also reported along with examples related to hull strength and structural components.

Keywords: dynamic analysis, finite element methods, ship structure, vibration analysis

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3200 Modelling Conceptual Quantities Using Support Vector Machines

Authors: Ka C. Lam, Oluwafunmibi S. Idowu

Abstract:

Uncertainty in cost is a major factor affecting performance of construction projects. To our knowledge, several conceptual cost models have been developed with varying degrees of accuracy. Incorporating conceptual quantities into conceptual cost models could improve the accuracy of early predesign cost estimates. Hence, the development of quantity models for estimating conceptual quantities of framed reinforced concrete structures using supervised machine learning is the aim of the current research. Using measured quantities of structural elements and design variables such as live loads and soil bearing pressures, response and predictor variables were defined and used for constructing conceptual quantities models. Twenty-four models were developed for comparison using a combination of non-parametric support vector regression, linear regression, and bootstrap resampling techniques. R programming language was used for data analysis and model implementation. Gross soil bearing pressure and gross floor loading were discovered to have a major influence on the quantities of concrete and reinforcement used for foundations. Building footprint and gross floor loading had a similar influence on beams and slabs. Future research could explore the modelling of other conceptual quantities for walls, finishes, and services using machine learning techniques. Estimation of conceptual quantities would assist construction planners in early resource planning and enable detailed performance evaluation of early cost predictions.

Keywords: bootstrapping, conceptual quantities, modelling, reinforced concrete, support vector regression

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3199 Formation of an Empire in the 21st Century: Theoretical Approach in International Relations and a Worldview of the New World Order

Authors: Rami Georg Johann

Abstract:

Against the background of the current geopolitical constellations, the author looks at various empire models, which are discussed and compared with each other with regard to their stability and functioning. The focus is on the fifth concept as a possible new world order in the 21st century. These will be discussed and compared to one another according to their stability and functioning. All empires to be designed will be conceptualised based on one, two, three, four, and five worlds. All worlds are made up of a different constellation of states and relating coalitions. All systems will be discussed in detail. The one-world-system, the“Western Empire,” will be presented as a possible solution to a new world order in the 21st century (fifth concept). The term “Western” in “Western Empire” describes the Western concept after World War II. This Western concept was the result of two horrible world wars in the 20th century.” With this in mind, the fifth concept forms a stable empire system, the “Western Empire,” by political measures tied to two issues. Thus, this world order provides a significantly higher long-term stability in contrast to all other empire models (comprising five, four, three, or two worlds). Confrontations and threats of war are reduced to a minimum. The two issues mentioned are “merger” and “competition.” These are the main differences in forming an empire compared to all empires and realms in the history of mankind. The fifth concept of this theory, the “Western Empire,” acts explicitly as a counter model. The Western Empire (fifth concept) is formed by the merger of world powers without war. Thus, a world order without competition is created. This merged entity secures long-term peace, stability, democratic values, freedom, human rights, equality, and justice in the new world order.

Keywords: empire formation, theory of international relations, Western Empire, world order

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3198 Research on Internet Attention of Tourism and Marketing Strategy in Northeast Sichuan Economic Zone in China Based on Baidu Index

Authors: Chuanqiao Zheng, Wei Zeng, Haozhen Lin

Abstract:

As of March 2020, the number of Chinese netizens has reached 904 million. The proportion of Internet users accessing the Internet through mobile phones is as high as 99.3%. Under the background of 'Internet +', tourists have a stronger sense of independence in the choice of tourism destinations and tourism products. Tourists are more inclined to learn about the relevant information on tourism destinations and other tourists' evaluations of tourist products through the Internet. The search engine, as an integrated platform that contains a wealth of information, is highly valuable to the analysis of the characteristics of the Internet attention given to various tourism destinations, through big data mining and analysis. This article uses the Baidu Index as the data source, which is one of the products of Baidu Search. The Baidu Index is based on big data, which collects and shares the search results of a large number of Internet users on the Baidu search engine. The big data used in this article includes search index, demand map, population profile, etc. The main research methods used are: (1) based on the search index, analyzing the Internet attention given to the tourism in five cities in Northeast Sichuan at different times, so as to obtain the overall trend and individual characteristics of tourism development in the region; (2) based on the demand map and the population profile, analyzing the demographic characteristics and market positioning of the tourist groups in these cities to understand the characteristics and needs of the target groups; (3) correlating the Internet attention data with the permanent population of each province in China in the corresponding to construct the Boston matrix of the Internet attention rate of the Northeast Sichuan tourism, obtain the tourism target markets, and then propose development strategies for different markets. The study has found that: a) the Internet attention given to the tourism in the region can be categorized into tourist off-season and peak season; the Internet attention given to tourism in different cities is quite different. b) tourists look for information including tour guide information, ticket information, traffic information, weather information, and information on the competing tourism cities; with regard to the population profile, the main group of potential tourists searching for the keywords of tourism in the five prefecture-level cities in Northeast Sichuan are youth. The male to female ratio is about 6 to 4, with males being predominant. c) through the construction of the Boston matrix, it is concluded that the star market for tourism in the Northeast Sichuan Economic Zone includes Sichuan and Shaanxi; the cash cows market includes Hainan and Ningxia; the question market includes Jiangsu and Shanghai; the dog market includes Hubei and Jiangxi. The study concludes with the following planning strategies and recommendations: i) creating a diversified business format that integrates cultural and tourism; ii) creating a brand image of niche tourism; iii) focusing on the development of tourism products; iv) innovating composite three-dimensional marketing channels.

Keywords: Baidu Index, big data, internet attention, tourism

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3197 Preparing a Library of Abnormal Masses for Designing a Long-Lasting Anatomical Breast Phantom for Ultrasonography Training

Authors: Nasibullina A., Leonov D.

Abstract:

The ultrasonography method is actively used for the early diagnosis of various le-sions in the human body, including the mammary gland. The incidence of breast cancer has increased by more than 20%, and mortality by 14% since 2008. The correctness of the diagnosis often directly depends on the qualifications and expe-rience of a diagnostic medical sonographer. That is why special attention should be paid to the practical training of future specialists. Anatomical phantoms are ex-cellent teaching tools because they accurately imitate the characteristics of real hu-man tissues and organs. The purpose of this work is to create a breast phantom for practicing ultrasound diagnostic skills in grayscale and elastography imaging, as well as ultrasound-guided biopsy sampling. We used silicone-like compounds ranging from 3 to 17 on the Shore scale hardness units to simulate soft tissue and lesions. Impurities with experimentally selected concentrations were added to give the phantom the necessary attenuation and reflection parameters. We used 3D modeling programs and 3D printing with PLA plastic to create the casting mold. We developed a breast phantom with inclusions of varying shape, elasticity and echogenicity. After testing the created phantom in B-mode and elastography mode, we performed a survey asking 19 participants how realistic the sonograms of the phantom were. The results showed that the closest to real was the model of the cyst with 9.5 on the 0-10 similarity scale. Thus, the developed breast phantom can be used for ultrasonography, elastography, and ultrasound-guided biopsy training.

Keywords: breast ultrasound, mammary gland, mammography, training phantom, tissue-mimicking materials

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3196 Contraception in Guatemala, Panajachel and the Surrounding Areas: Barriers Affecting Women’s Contraceptive Usage

Authors: Natasha Bhate

Abstract:

Contraception is important in helping to reduce maternal and infant mortality rates by allowing women to control the number and spacing in-between their children. It also reduces the need for unsafe abortions. Women worldwide use contraception; however, the contraceptive prevalence rate is still relatively low in Central American countries like Guatemala. There is also an unmet need for contraception in Guatemala, which is more significant in rural, indigenous women due to barriers preventing contraceptive use. The study objective was to investigate and analyse the current barriers women face, in Guatemala, Panajachel and the surrounding areas, in using contraception, with a view of identifying ways to overcome these barriers. This included exploring the contraceptive barriers women believe exist and the influence of males in contraceptive decision making. The study took place at a charity in Panajachel, Guatemala, and had a cross-sectional, qualitative design to allow an in-depth understanding of information gathered. This particular study design was also chosen to help inform the charity with qualitative research analysis, in view of their intent to create a local reproductive health programme. A semi-structured interview design, including photo facilitation to improve cross-cultural communication, with interpreter assistance, was utilized. A pilot interview was initially conducted with small improvements required. Participants were recruited through purposive and convenience sampling. The study host at the charity acted as a gatekeeper; participants were identified through attendance of the charity’s women’s-initiative programme workshops. 20 participants were selected and agreed to study participation with two not attending; a total of 18 participants were interviewed in June 2017. Interviews were audio-recorded and data were stored on encrypted memory sticks. Framework analysis was used to analyse the data using NVivo11 software. The University of Leeds granted ethical approval for the research. Religion, language, the community, and fear of sickness were examples of existing contraceptive barrier themes recognized by many participants. The influence of men was also an important barrier identified, with themes of machismo and abuse preventing contraceptive use in some women. Women from more rural areas were believed to still face barriers which some participants did not encounter anymore, such as distance and affordability of contraceptives. Participants believed that informative workshops in various settings were an ideal method of overcoming existing contraceptive barriers and allowing women to be more empowered. The involvement of men in such workshops was also deemed important by participants to help reduce their negative influence in contraceptive usage. Overall, four recommendations following this study were made, including contraceptive educational courses, a gender equality campaign, couple-focused contraceptive workshops, and further qualitative research to gain a better insight into men’s opinions regarding women using contraception.

Keywords: barrier, contraception, machismo, religion

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3195 Molecular Dynamics Simulation for Vibration Analysis at Nanocomposite Plates

Authors: Babak Safaei, A. M. Fattahi

Abstract:

Polymer/carbon nanotube nanocomposites have a wide range of promising applications Due to their enhanced properties. In this work, free vibration analysis of single-walled carbon nanotube-reinforced composite plates is conducted in which carbon nanotubes are embedded in an amorphous polyethylene. The rule of mixture based on various types of plate model namely classical plate theory (CLPT), first-order shear deformation theory (FSDT), and higher-order shear deformation theory (HSDT) was employed to obtain fundamental frequencies of the nanocomposite plates. Generalized differential quadrature (GDQ) method was used to discretize the governing differential equations along with the simply supported and clamped boundary conditions. The material properties of the nanocomposite plates were evaluated using molecular dynamic (MD) simulation corresponding to both short-(10,10) SWCNT and long-(10,10) SWCNT composites. Then the results obtained directly from MD simulations were fitted with those calculated by the rule of mixture to extract appropriate values of carbon nanotube efficiency parameters accounting for the scale-dependent material properties. The selected numerical results are presented to address the influences of nanotube volume fraction and edge supports on the value of fundamental frequency of carbon nanotube-reinforced composite plates corresponding to both long- and short-nanotube composites.

Keywords: nanocomposites, molecular dynamics simulation, free vibration, generalized, differential quadrature (GDQ) method

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3194 Reorientation of Anisotropic Particles in Free Liquid Microjets

Authors: Mathias Schlenk, Susanne Seibt, Sabine Rosenfeldt, Josef Breu, Stephan Foerster

Abstract:

Thin liquid jets on micrometer scale play an important role in processing such as in fiber fabrication, inkjet printing, but also for sample delivery in modern synchrotron X-ray devices. In all these cases the liquid jets contain solvents and dissolved materials such as polymers, nanoparticles, fibers pigments or proteins. As liquid flow in liquid jets differs significantly from flow in capillaries and microchannels, particle localization and orientation will also be different. This is of critical importance for applications, which depend on well-defined homogeneous particle and fiber distribution and orientation in liquid jets. Investigations of particle orientation in liquid microjets of diluted solutions have been rare, despite their importance. With the arise of micro-focused X-ray beams it has become possible to scan across samples with micrometer resolution to locally analyse structure and orientation of the samples. In the present work, we used this method to scan across liquid microjets to determine the local distribution and orientation of anisotropic particles. The compromise wormlike block copolymer micelles as an example of long flexible fibrous structures, hectorite materials as a model of extended nanosheet structures, and gold nanorods as an illustration of short stiff cylinders to comprise all relevant anisotropic geometries. We find that due to the different velocity profile in the liquid jet, which resembles plug flow, the orientation of the particles which was generated in the capillary is lost or changed into non-oriented or bi-axially orientations depending on the geometrical shape of the particle.

Keywords: anisotropic particles, liquid microjets, reorientation, SAXS

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3193 The Impact of Reshuffle in Indonesian Working Cabinet Volume II to Abnormal Return and Abnormal Trading Activity of Companies Listed in the Jakarta Islamic Index

Authors: Fatin Fadhilah Hasib, Dewi Nuraini, Nisful Laila, Muhammad Madyan

Abstract:

A big political event such as Cabinet reshuffle mostly can affect the stock price positively or negatively, depend on the perception of each investor and potential investor. This study aims to analyze the movement of the market and trading activities which respect to an event using event study method. This method is used to measure the movement of the stock exchange in which abnormal return can be obtained by investor related to the event. This study examines the differences of reaction on abnormal return and trading volume activity from the companies listed in the Jakarta Islamic Index (JII), before and after the announcement of the Cabinet Work Volume II on 27 July 2016. The study was conducted in observation of 21 days in total which consists of 10 days before the event and 10 days after the event. The method used in this study is event study with market adjusted model method that observes market reaction to the information of an announcement or publicity events. The Results from the study showed that there is no significant negative nor positive reaction at the abnormal return and abnormal trading before and after the announcement of the cabinet reshuffle. It is indicated by the results of statistical tests whose value not exceeds the level of significance. Stock exchange of the JII just reflects from the previous stock prices without reflecting the information regarding to the Cabinet reshuffle event. It can be concluded that the capital market is efficient with a weak form.

Keywords: abnormal return, abnormal trading volume activity, event study, political event

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3192 Evaluation of the Performance Measures of Two-Lane Roundabout and Turbo Roundabout with Varying Truck Percentages

Authors: Evangelos Kaisar, Anika Tabassum, Taraneh Ardalan, Majed Al-Ghandour

Abstract:

The economy of any country is dependent on its ability to accommodate the movement and delivery of goods. The demand for goods movement and services increases truck traffic on highways and inside the cities. The livability of most cities is directly affected by the congestion and environmental impacts of trucks, which are the backbone of the urban freight system. Better operation of heavy vehicles on highways and arterials could lead to the network’s efficiency and reliability. In many cases, roundabouts can respond better than at-level intersections to enable traffic operations with increased safety for both cars and heavy vehicles. Recently emerged, the concept of turbo-roundabout is a viable alternative to the two-lane roundabout aiming to improve traffic efficiency. The primary objective of this study is to evaluate the operation and performance level of an at-grade intersection, a conventional two-lane roundabout, and a basic turbo roundabout for freight movements. To analyze and evaluate the performances of the signalized intersections and the roundabouts, micro simulation models were developed PTV VISSIM. The networks chosen for this analysis in this study are to experiment and evaluate changes in the performance of the movement of vehicles with different geometric and flow scenarios. There are several scenarios that were examined when attempting to assess the impacts of various geometric designs on vehicle movements. The overall traffic efficiency depends on the geometric layout of the intersections, which consists of traffic congestion rate, hourly volume, frequency of heavy vehicles, type of road, and the ratio of major-street versus side-street traffic. The traffic performance was determined by evaluating the delay time, number of stops, and queue length of each intersection for varying truck percentages. The results indicate that turbo-roundabouts can replace signalized intersections and two-lane roundabouts only when the traffic demand is low, even with high truck volume. More specifically, it is clear that two-lane roundabouts are seen to have shorter queue lengths compared to signalized intersections and turbo-roundabouts. For instance, considering the scenario where the volume is highest, and the truck movement and left turn movement are maximum, the signalized intersection has 3 times, and the turbo-roundabout has 5 times longer queue length than a two-lane roundabout in major roads. Similarly, on minor roads, signalized intersections and turbo-roundabouts have 11 times longer queue lengths than two-lane roundabouts for the same scenario. As explained from all the developed scenarios, while the traffic demand lowers, the queue lengths of turbo-roundabouts shorten. This proves that turbo roundabouts perform well for low and medium traffic demand. The results indicate that turbo-roundabouts can replace signalized intersections and two-lane roundabouts only when the traffic demand is low, even with high truck volume. Finally, this study provides recommendations on the conditions under which different intersections perform better than each other.

Keywords: At-grade intersection, simulation, turbo-roundabout, two-lane roundabout

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3191 Theoretical-Experimental Investigations on Free Vibration of Glass Fiber/Polyester Composite Conical Shells Containing Fluid

Authors: Tran Ich Thinh, Nguyen Manh Cuong

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Free vibrations of partial fluid-filled composite truncated conical shells are investigated using the Dynamic Stiffness Method (DSM) or Continuous Element Method (CEM) based on the First Order Shear Deformation Theory (FSDT) and non-viscous incompressible fluid equations. Numerical examples are given for analyzing natural frequencies and harmonic responses of clamped-free conical shells partially and completely filled with fluid. To compare with the theoretical results, detailed experimental results have been obtained on the free vibration of a clamped-free conical shells partially filled with water by using a multi-vibration measuring machine (DEWEBOOK-DASYLab 5.61.10). Three glass fiber/polyester composite truncated cones with the radius of the larger end 285 mm, thickness 2 mm, and the cone lengths along the generators are 285 mm, 427.5 mm and 570 mm with the semi-vertex angles 27, 14 and 9 degrees respectively were used, and the filling ratio of the contained water was 0, 0.25, 0.50, 0.75 and 1.0. The results calculated by proposed computational model for studied composite conical shells are in good agreement with experiments. Obtained results indicate that the fluid filling can reduce significantly the natural frequencies of composite conical shells. Parametric studies including circumferential wave number, fluid depth and cone angles are carried out.

Keywords: dynamic stiffness method, experimental study, free vibration, fluid-shell interaction, glass fiber/polyester composite conical shell

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3190 Analysis of Lesotho Wool Production and Quality Trends 2008-2018

Authors: Papali Maqalika

Abstract:

Lesotho farmers produce significant quantities of Merino wool of a quality competitive on the global market and make a substantial impact on the economy of Lesotho. However, even with the economic contribution, the production and quality information and trends of this fibre has been recognised nor documented. This is a sombre shortcoming as Lesotho wool is unknown on international markets. The situation is worsened by the fact that Lesotho wool is auction together with South African wool, trading and benchmarking Lesotho wool are difficult not to mention attempts to advance its production and quality. Based on the information above, available data on Lesotho wool for 10 years were collected and analysed for trends to used in benchmarking where applicable. The fibre properties analysed include fibre diameter (fineness), vegetable matter and yield, application and price. These were selected because they are fundamental in determining fibre quality and price. Production of wool in Lesotho has increased slightly over the ten years covered by this study. It also became apparent that production and quality trends of Lesotho wool are greatly influenced by the farming practices, breed of sheep and climatic conditions. Greater adoption of the merino sheep breed, sheds/barns and sheep coats are suggested as ways to reduce mortality rate (due to extremely cold temperatures), to reduce the vegetable matter on the fibre thus improving the quality and increase yield per sheep and production as a whole. Some farming practices such as the lack of barns, supplementary feeding and veterinary care present constraints in wool production. The districts in the Highlands region were found to have the highest production of mostly wool, this being ascribed to better pastures, climatic, social and other conditions conducive to wool production. The production of Lesotho wool and its quality can be improved further, possibly because of the interventions the Ministry of Agriculture introduced through the Small Agricultural and Development Project (SADP) and other appropriate initiatives by the National Wool and Mohair Growers Association (NWMGA). The challenge however, remains the lack of direct involvement of the wool growers (farmers) in decisions making and policy development, this potentially influences and may lead to the reluctance to adopt the strategies. In some cases, the wool growers do not receive the benefits associated with the interventions immediately. Based on these discoveries; it is recommended that the relevant educators and researchers in wool and textile science, as well as the local wool farmers in Lesotho, be represented in policy and other decision making forums relating to these interventions. In this way, educational campaigns and training workshops will be demand driven with a better chance of adoption and success. This is because the direct beneficiaries will have been involved at inception and they will have a sense of ownership as well as intent to see them through successfully.

Keywords: lesotho wool, wool quality, wool production, lesotho economy, global market, apparel wool, database, textile science, exports, animal farming practices, intimate apparel, interventions

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3189 Optimizing the Morphology and Flow Patterns of Scaffold Perfusion Systems for Effective Cell Deposition Using Computational Fluid Dynamics

Authors: Vineeth Siripuram, Abhineet Nigam

Abstract:

A bioreactor is an engineered system that supports a biologically active environment. Along the years, the advancements in bioreactors have been widely accepted all over the world for varied applications ranging from sewage treatment to tissue cloning. Driven by tissue and organ shortage, tissue engineering has emerged as an alternative to transplantation for the reconstruction of lost or damaged organs. In this study, Computational fluid dynamics (CFD) has been used to model porous medium flow in scaffolds (taken from the literature) with different flow patterns. A detailed analysis of different scaffold geometries and their influence on cell deposition in the perfusion system is been carried out using Computational fluid dynamics (CFD). Considering the fact that, the scaffold should mimic the organs or tissues structures in a three-dimensional manner, certain assumptions were made accordingly. The research on scaffolds has been extensively carried out in different bioreactors. However, there has been less focus on the morphology of the scaffolds and the flow patterns in which the perfusion system is laid upon. The objective of this paper is to employ a computational approach using CFD simulation to determine the optimal morphology and the anisotropic measurements of the various samples of scaffolds. Using predictive computational modelling approach, variables which exert dominant effects on the cell deposition within the scaffold were prioritised and corresponding changes in morphology of scaffold and flow patterns in the perfusion systems are made. A Eulerian approach was carried on in multiple CFD simulations, and it is observed that the morphological and topological changes in the scaffold perfusion system are of great importance in the commercial applications of scaffolds.

Keywords: cell seeding, CFD, flow patterns, modelling, perfusion systems, scaffold

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3188 Computational Fluid Dynamics (CFD) Simulation Approach for Developing New Powder Dispensing Device

Authors: Revanth Rallapalli

Abstract:

Manually dispensing solids and powders can be difficult as it requires gradually pour and check the amount on the scale to be dispensed. Current systems are manual and non-continuous in nature and are user-dependent and difficult to control powder dispensation. Recurrent dosing of powdered medicines in precise amounts quickly and accurately has been an all-time challenge. Various new powder dispensing mechanisms are being designed to overcome these challenges. A battery-operated screw conveyor mechanism is being innovated to overcome the above problems faced. These inventions are numerically evaluated at the concept development level by employing Computational Fluid Dynamics (CFD) of gas-solids multiphase flow systems. CFD has been very helpful in development of such devices saving time and money by reducing the number of prototypes and testing. Furthermore, this paper describes a simulation of powder dispensation from the trocar’s end by considering the powder as secondary flow in air, is simulated by using the technique called Dense Discrete Phase Model incorporated with Kinetic Theory of Granular Flow (DDPM-KTGF). By considering the volume fraction of powder as 50%, the transportation of powder from the inlet side to trocar’s end side is done by rotation of the screw conveyor. Thus, the performance is calculated for a 1-sec time frame in an unsteady computation manner. This methodology will help designers in developing design concepts to improve the dispensation and also at the effective area within a quick turnaround time frame.

Keywords: DDPM-KTGF, gas-solids multiphase flow, screw conveyor, Unsteady

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3187 Characterization of Kopff Crater Using Remote Sensing Data

Authors: Shreekumari Patel, Prabhjot Kaur, Paras Solanki

Abstract:

Moon Mineralogy Mapper (M3), Miniature Radio Frequency (Mini-RF), Kaguya Terrain Camera images, Lunar Orbiter Laser Altimeter (LOLA) digital elevation model (DEM) and Lunar Reconnaissance Orbiter Camera (LROC)- Narrow angle camera (NAC) and Wide angle camera (WAC) images were used to study mineralogy, surface physical properties, and age of the 42 km diameter Kopff crater. M3 indicates the low albedo crater floor to be high-Ca pyroxene dominated associated with floor fracture suggesting the igneous activity of the gabbroic material. Signature of anorthositic material is sampled on the eastern edge as target material is excavated from ~3 km diameter impact crater providing access to the crustal composition. Several occurrences of spinel were detected in northwestern rugged terrain. Our observation can be explained by exposure of spinel by this crater that impacted onto the inner rings of Orientale basin. Spinel was part of the pre-impact target, an intrinsic unit of basin ring. Crater floor was dated by crater counts performed on Kaguya TC images. Nature of surface was studied in detail with LROC NAC and Mini-RF. Freshly exposed surface and boulder or debris seen in LROC NAC images have enhanced radar signal in comparison to mature terrain of Kopff crater. This multidisciplinary analysis of remote sensing data helps to assess lunar surface in detail.

Keywords: crater, mineralogy, moon, radar observations

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3186 Prevalence and Determinants of Hypertension among the Santal Indigenous Group in Bangladesh

Authors: Sharmin Sultana, Palash Chandra Banik, Shirin Jahan Mumu, Liaquat Ali

Abstract:

Santals are one of the oldest indigenous groups of South Asia who, according to anthropological evidence, are thought to be the origins of the Bengali race. The aim of the study was to explore, according to our best knowledge for the first time, the prevalence and determinants of hypertension in this relatively isolated and marginalized indigenous group who still live mostly in a traditional style. Under a cross-sectional analytical design, the study was conducted on the adult (age≥18 years) Santals (n=389, M/F 184/205, age in years, 38±15.3) of a village located in a remote rural area of northern Bangladesh. Subjects were selected by purposive sampling, and data were collected by interviewer-administered pretested questionnaire. Blood pressure was measured by following the WHO guideline of JNC-7 has been used to classify the blood pressure. The prevalence of hypertension was 4.9% among the respondents. Females had a much higher prevalence (5.4%) of hypertension compared to males (4.3%). Among the risk indicators of hypertension, more than half (50.9%) of the study population took extra salt in their meals, whereas 10.5% of respondents used extra salt occasionally, which is an important risk factor for high blood pressure. High waist circumference was found in 19% of the study subjects in terms of central obesity. Older age group (p=0.003, OR=1.1, 95%CI-1.02-1.10), respondents who completed more than primary school (p=0.038, OR=7.1, CI-1.11, 44.6), overweight and obesity (p=0.004, OR=17.1, CI-2.5, 118.1), were the major determinant for hypertension as found from the binary logistic model. None of the respondents received any medication, neither they visit any doctor ever for their hypertension control. The prevalence of hypertension was found to be low but not ignorable. Pre-hypertension in the case of systolic blood pressure needs attention among Santal indigenous population.

Keywords: hypertension, indigenous group, Santals, Bangladesh

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3185 Effectiveness of Parent Coaching Intervention for Parents of Children with Developmental Disabilities in the Home and Community

Authors: Elnaz Alimi, Keriakoula Andriopoulos, Sam Boyer, Weronika Zuczek

Abstract:

Occupational therapists can use coaching strategies to guide parents in providing therapy for their children with developmental disabilities. Evidence from various fields has shown increased parental self-efficacy and positive child outcomes as benefits of home and community-based parent coaching models. A literature review was conducted to investigate the effectiveness of parent coaching interventions delivered in home and community settings for children with developmental disabilities ages 0-12, on a variety of parent and child outcomes. CINAHL Plus, PsycINFO, PubMed, OTseeker were used as databases. The inclusion criteria consisted of: children with developmental disabilities ages 0-12 and their parents, parent coaching models conducted in the home and community, and parent and child outcomes. Studies were excluded if they were in a language other than English and published before 2000. Results showed that parent coaching interventions led to more positive therapy outcomes in child behaviors and symptoms related to their diagnosis or disorder. Additionally, coaching strategies had positive effects on parental satisfaction with therapy, parental self-efficacy, and family dynamics. Findings revealed decreased parental stress and improved parent-child relationships. Further research on parent coaching could involve studying the feasibility of coaching within occupational therapy specifically, incorporating cultural elements into coaching, qualitative studies on parental satisfaction with coaching, and measuring the quality of life outcomes for the whole family.

Keywords: coaching model, developmental disabilities, occupational therapy, pediatrics

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3184 Stigma Associated with Invisible Disabilities and Its Effect on Intended Disclosure in the Workplace

Authors: Jessica Lynne Hicksted

Abstract:

Disability discrimination is a long-standing issue that, despite protections, continues to result in unemployment, underemployment, and lack of advancement for disabled persons. Visible stigma is researched substantially; however, less is known about the impact of stigma associated with identities that can be concealed. Although researchers have investigated this issue, currently there is no tool to measure this phenomenon. The purpose of this quantitative study was to create and validate a new tool to measure stigma associated with invisible disabilities. The study is grounded by Roberts’ conceptual model of professional image construction integrating social identity, impression management, and organizational behavior; Meisenbach’s stigma management communication theory addressing the vulnerabilities and resilience to stigma communication by focusing on how individuals encounter and react to perceived stigmas; and Kelley and Michela’s causal attribution theory. Participants included 1,412 adults in the United States 18 years or older currently employed or who have been employed within the last 5 years. Confirmatory factor analysis of the new Workplace Invisible Disabilities Experience scale showed excellent fit of the factor structure to the data, X₂/df = 1.855, CFI = .955, RMSEA = .045, p = .0001. The scale has three subscales, Ableism, Advocacy, and Acceptance, with excellent internal consistency reliability. Total score, Advocacy, and Acceptance were associated with intention to disclose. Implications for positive social change include helping organizations to understand the extent of invisible disability stigma that can help improve workplace performance and satisfaction.

Keywords: invisible disabilities, accommodations, acceptance, social change, workplace inclusion

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3183 Effects of Clozapine and Risperidone Antipsychotic Drugs on the Expression of CACNA1C and Behavioral Changes in Rat ‘Ketamine Model of Schizophrenia

Authors: Mehrnoosh Azimi Sanavi, Hamed Ghazvini, Mehryar Zargari, Hossein Ghalehnoei, Zahra Hosseini-khah

Abstract:

Objectives: Calcium Voltage-Gated Channel Subunit Alpha1 C (CACNA1C) is one of the most important genes associated with schizophrenia. Methods: 45 male Wistar rats were divided into 5 groups: saline, control, ketamine, clozapine, and risperidone. Animals in ketamine, risperidone, and clozapine groups received ketamine (30 mg/ kg-i.p.) for 10 days. After the last injection of ketamine, we started injecting clozapine (7.5 mg/kg-i.p.) risperidone (1 mg/kg-i.p.) for up to 28 days. Twenty-four hours after the last injection, open field, social interaction, and elevated plus-maze tests, and gene expression in the hippocampus were performed. Results: The results of the social interaction test revealed a significant decrease in cumulative time with ketamine compared with the saline group and an increase with clozapine and risperidone compared with the ketamine group. Moreover, results from the elevated plus-maze test demonstrated a critical decrease in open-arm time and an increase in close-arm time with ketamine compared with saline, as well as an increase in open-arm time with risperidone compared with ketamine. Further results revealed a significant increase in rearing and grooming with ketamine compared to saline, as well as a decrease with risperidone and clozapine compared to ketamine. There were no significant differences in CACNA1C gene expression between groups in the rat hippocampus. In brief, the results of this study indicated that clozapine and risperidone could partially improve cognitive impairments in the rat. However, our findings demonstrated that this treatment is not related to CACNA1C gene expression.

Keywords: schizophrenia, ketamine, clozapine, risperidone

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3182 Comparative Stem Cells Therapy for Regeneration of Liver Fibrosis

Authors: H. M. Imam, H. M. Rezk, A. F. Tohamy

Abstract:

Background: Human umbilical cord blood (HUCB) is considered as a unique source for stem cells. HUCB contain different types of progenitor cells which could differentiate into hepatocytes. Aims: To investigate the potential of rat's liver damage repair using human umbilical cord mesenchymal stem cells (hUCMSCs). We investigated the feasibility for hUCMSCs in recovery from liver damage. Moreover, investigating fibrotic liver repair and using the CCl4-induced model for liver damage in the rat. Methods: Rats were injected with 0.5 ml/kg CCl4 to induce liver damage and progressive liver fibrosis. hUCMSCs were injected into the rats through the tail vein; Stem cells were transplanted at a dose of 1×106 cells/rat after 72 hours of CCl4 injection without receiving any immunosuppressant. After (6 and 8 weeks) of transplantation, blood samples were collected to assess liver functions (ALT, AST, GGT and ALB) and level of Procollagen III as a liver fibrosis marker. In addition, hepatic tissue regeneration was assessed histopathologically and immunohistochemically using antihuman monoclonal antibodies against CD34, CK19 and albumin. Results: Biochemical and histopathological analysis showed significantly increased recovery from liver damage in the transplanted group. In addition, HUCB stem cells transdifferentiated into functional hepatocytes in rats with hepatic injury which results in improving liver structure and function. Conclusion: Our findings suggest that transplantation of hUCMSCs may be a novel therapeutic approach for treating liver fibrosis. Therefore, hUCMSCs are a potential option for treatment of liver cirrhosis.

Keywords: carbon tetra chloride, liver fibrosis, mesenchymal stem cells, rat

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3181 A Study on Functional Performance and Physical Self-esteem Levels of Differently-Abled Basket Ballplayers: A Case Series

Authors: Prerna Mohan Saxena, Avni Joshi, Raju K Parasher

Abstract:

Disability is a state of decreased functioning associated with disease, disorder, injury, or other health condition, which in the context of one’s environment is experienced as an impairment, activity limitation, or participation restriction. With the concept of disability evolving over the years, the current ICF model of disability has integrated this concept into a comprehensive whole of multiple dimensions of human functioning, including biological, psychological, social, and environmental aspects. Wheelchair basketball is one of the greatest examples of adapted sports for the disabled. Through this study, we aim to evaluate the functional performance and self-esteem levels in differently-abled pediatric wheelchair basketball players, providing an insight on their abilities and deficits and how they can be worked on at a larger level to improve overall performance. The study was conducted on 9 pediatric wheelchair basketball players at Amar Jyoti school for inclusive education Delhi their physical performance was assessed using a battery of tests, and physical self esteem was assessed using the Physical self-description instrument (PSDQ-S). Results showed that 9 participants age ranged between 10-21 years, mostly males with BMI ranging between 16.7 to 28.9 kg/m2 most of them had the experience of 5 to 6 years of playing the sport. The data showed physical performance in accordance to years of experience of playing, physical self esteem showed a different perspective, with experience players scoring less on it. This study supports a multidimensional construct of physical performance and physical self-esteem, suggesting that both may be applied on the wheelchair basketball players at competitive levels.

Keywords: ase series, physical performance, physical self-esteem, wheelchair basketball

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3180 Emerging Issues for Global Impact of Foreign Institutional Investors (FII) on Indian Economy

Authors: Kamlesh Shashikant Dave

Abstract:

The global financial crisis is rooted in the sub-prime crisis in U.S.A. During the boom years, mortgage brokers attracted by the big commission, encouraged buyers with poor credit to accept housing mortgages with little or no down payment and without credit check. A combination of low interest rates and large inflow of foreign funds during the booming years helped the banks to create easy credit conditions for many years. Banks lent money on the assumptions that housing price would continue to rise. Also the real estate bubble encouraged the demand for houses as financial assets .Banks and financial institutions later repackaged these debts with other high risk debts and sold them to worldwide investors creating financial instruments called collateral debt obligations (CDOs). With the rise in interest rate, mortgage payments rose and defaults among the subprime category of borrowers increased accordingly. Through the securitization of mortgage payments, a recession developed in the housing sector and consequently it was transmitted to the entire US economy and rest of the world. The financial credit crisis has moved the US and the global economy into recession. Indian economy has also affected by the spill over effects of the global financial crisis. Great saving habit among people, strong fundamentals, strong conservative and regulatory regime have saved Indian economy from going out of gear, though significant parts of the economy have slowed down. Industrial activity, particularly in the manufacturing and infrastructure sectors decelerated. The service sector too, slow in construction, transport, trade, communication, hotels and restaurants sub sectors. The financial crisis has some adverse impact on the IT sector. Exports had declined in absolute terms in October. Higher inputs costs and dampened demand have dented corporate margins while the uncertainty surrounding the crisis has affected business confidence. To summarize, reckless subprime lending, loose monetary policy of US, expansion of financial derivatives beyond acceptable norms and greed of Wall Street has led to this exceptional global financial and economic crisis. Thus, the global credit crisis of 2008 highlights the need to redesign both the global and domestic financial regulatory systems not only to properly address systematic risk but also to support its proper functioning (i.e financial stability).Such design requires: 1) Well managed financial institutions with effective corporate governance and risk management system 2) Disclosure requirements sufficient to support market discipline. 3)Proper mechanisms for resolving problem institution and 4) Mechanisms to protect financial services consumers in the event of financial institutions failure.

Keywords: FIIs, BSE, sensex, global impact

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3179 Cache Analysis and Software Optimizations for Faster on-Chip Network Simulations

Authors: Khyamling Parane, B. M. Prabhu Prasad, Basavaraj Talawar

Abstract:

Fast simulations are critical in reducing time to market in CMPs and SoCs. Several simulators have been used to evaluate the performance and power consumed by Network-on-Chips. Researchers and designers rely upon these simulators for design space exploration of NoC architectures. Our experiments show that simulating large NoC topologies take hours to several days for completion. To speed up the simulations, it is necessary to investigate and optimize the hotspots in simulator source code. Among several simulators available, we choose Booksim2.0, as it is being extensively used in the NoC community. In this paper, we analyze the cache and memory system behaviour of Booksim2.0 to accurately monitor input dependent performance bottlenecks. Our measurements show that cache and memory usage patterns vary widely based on the input parameters given to Booksim2.0. Based on these measurements, the cache configuration having least misses has been identified. To further reduce the cache misses, we use software optimization techniques such as removal of unused functions, loop interchanging and replacing post-increment operator with pre-increment operator for non-primitive data types. The cache misses were reduced by 18.52%, 5.34% and 3.91% by employing above technology respectively. We also employ thread parallelization and vectorization to improve the overall performance of Booksim2.0. The OpenMP programming model and SIMD are used for parallelizing and vectorizing the more time-consuming portions of Booksim2.0. Speedups of 2.93x and 3.97x were observed for the Mesh topology with 30 × 30 network size by employing thread parallelization and vectorization respectively.

Keywords: cache behaviour, network-on-chip, performance profiling, vectorization

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3178 Numerical Analysis of the Effect of Geocell Reinforcement above Buried Pipes on Surface Settlement and Vertical Pressure

Authors: Waqed H. Almohammed, Mohammed Y. Fattah, Sajjad E. Rasheed

Abstract:

Dynamic traffic loads cause deformation of underground pipes, resulting in vehicle discomfort. This makes it necessary to reinforce the layers of soil above underground pipes. In this study, the subbase layer was reinforced. Finite element software (PLAXIS 3D) was used to in the simulation, which includes geocell reinforcement, vehicle loading, soil layers and Glass Fiber Reinforced Plastic (GRP) pipe. Geocell reinforcement was modeled using a geogrid element, which was defined as a slender structure element that has the ability to withstand axial stresses but not to resist bending. Geogrids cannot withstand compression but they can withstand tensile forces. Comparisons have been made between the numerical models and experimental works, and a good agreement was obtained. Using the mathematical model, the performance of three different pipes of diameter 600 mm, 800 mm, and 1000 mm, and three different vehicular speeds of 20 km/h, 40 km/h, and 60 km/h, was examined to determine their impact on surface settlement and vertical pressure at the pipe crown for two cases: with and without geocell reinforcement. The results showed that, for a pipe diameter of 600 mm under geocell reinforcement, surface settlement decreases by 94 % when the speed of the vehicle is 20 km/h and by 98% when the speed of the vehicle is 60 km/h. Vertical pressure decreases by 81 % when the diameter of the pipe is 600 mm, while the value decreases to 58 % for a pipe with diameter 1000 mm. The results show that geocell reinforcement causes a significant and positive reduction in surface settlement and vertical stress above the pipe crown, leading to an increase in pipe safety.

Keywords: dynamic loading, finite element, geocell-reinforcement, GRP pipe, PLAXIS 3D, surface settlement

Procedia PDF Downloads 237