Search results for: temporary railway bridge
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1336

Search results for: temporary railway bridge

736 A Case Study on Tension Drop of Cable-band Bolts in Suspension Bridge

Authors: Sihyun Park, Hyunwoo Kim, Wooyoung Jung, Dongwoo You

Abstract:

Regular maintenance works are very important on the axial forces of the cable-band bolts in suspension bridges. The band bolts show stress reduction for several reasons, including cable wire creep, the bolt relaxation, load fluctuation and cable rearrangements, etc., with time. In this study, with respect to the stress reduction that occurs over time, we carried out the theoretical review of the main cause based on the field measurements. As a result, the main cause of reduction in the cable-band bolt axial force was confirmed by the plastic deformation of the zinc plating layer used in the main cable wire, and thus, the theoretical process was established for the practical use in the field.

Keywords: cable-band Bolts, field test, maintenance, stress reduction

Procedia PDF Downloads 322
735 Assessing the Adaptive Re-Use Potential of Buildings as Part of the Disaster Management Process

Authors: A. Esra İdemen, Sinan M. Şener, Emrah Acar

Abstract:

The technological paradigm of the disaster management field, especially in the case of governmental intervention strategies, is generally based on rapid and flexible accommodation solutions. From various technical solution patterns used to address the immediate housing needs of disaster victims, the adaptive re-use of existing buildings can be considered to be both low-cost and practical. However, there is a scarcity of analytical methods to screen, select and adapt buildings to help decision makers in cases of emergency. Following an extensive literature review, this paper aims to highlight key points and problem areas associated with the adaptive re-use of buildings within the disaster management context. In other disciplines such as real estate management, the adaptive re-use potential (ARP) of existing buildings is typically based on the prioritization of a set of technical and non-technical criteria which are then weighted to arrive at an economically viable investment decision. After a disaster, however, the assessment of the ARP of buildings requires consideration of different/additional layers of analysis which stem from general disaster management principles and the peculiarities of different types of disasters, as well as of their victims. In this paper, a discussion of the development of an adaptive re-use potential (ARP) assessment model is presented. It is thought that governmental and non-governmental decision makers who are required to take quick decisions to accommodate displaced masses following disasters are likely to benefit from the implementation of such a model.

Keywords: adaptive re-use of buildings, disaster management, temporary housing, assessment model

Procedia PDF Downloads 320
734 Growth of New Media Advertising

Authors: Palwinder Bhatia

Abstract:

As all know new media is a broad term in media studies that emerged in the latter part of the 20th century which refers to on-demand access to content any time, anywhere, on any digital device, as well as interactive user feedback, creative participation and community formation around the media content. The role of new media in advertisement is impeccable these days. It becomes the cheap and best way of advertising. Another important promise of new media is the democratization of the creation, publishing, distribution and consumption of media content. New media brings a revolution in about every field. It makes bridge between customer and companies. World make a global village with the only help of new media. Advertising helps in shaping the consumer behavior and effect on consumer psychology, sociology, social anthropology and economics. People do comments and like the particular brands on the networking sites which create mesmerism impact on the behavior of customer. Recent study did by Times of India shows that 64% of Facebook users have liked a brand on Facebook.

Keywords: film, visual, culture, media, advertisement

Procedia PDF Downloads 270
733 Development of Temple Architecture during the Reign of Kalachuri’s of Tripuri

Authors: Shivam Dubey, Shivakant Bajpai

Abstract:

The Kalachuri dynasty of Tripuri was a significant ruling dynasty in central India that held power over a vast region for a longer period compared to renowned dynasties like the Chandellas. Their capital, Tripuri (modern-day Tewar, a small village near Jabalpur), and its surrounding area witnessed significant developments that were later disrupted by the Royal Indian Railways' construction of railway lines. However, remnants of their achievements can still be found scattered in and around Tewar. The Kalachuris made remarkable contributions in the fields of art, architecture, and iconography. The evolution of temple architecture, particularly in Baghelkhand and the Mahakoshal range after the decline of the Gupta Empire, can be attributed to the Kalachuris. There is a notable progression from early temple styles to mature architecture, with numerous examples displaying continuity between the two. One particularly unique temple style features a ground plan resembling a complete Chaitya Hall, while the elevation showcases a circular Grabhagriha with a Mandapa and a conical Shikhara adorned with a series of Gavakshas. This distinctive temple style is among the most exceptional in central India. While several studies have been conducted on the Kalachuris' architecture, there is still a need for further research, as recent discoveries have provided valuable insights into understanding their architectural achievements. This paper aims to explore the development of architecture in this region, incorporating these recent findings.

Keywords: architecture, Kalachuri, art, iconography

Procedia PDF Downloads 62
732 Approach for Demonstrating Reliability Targets for Rail Transport during Low Mileage Accumulation in the Field: Methodology and Case Study

Authors: Nipun Manirajan, Heeralal Gargama, Sushil Guhe, Manoj Prabhakaran

Abstract:

In railway industry, train sets are designed based on contractual requirements (mission profile), where reliability targets are measured in terms of mean distance between failures (MDBF). However, during the beginning of revenue services, trains do not achieve the designed mission profile distance (mileage) within the timeframe due to infrastructure constraints, scarcity of commuters or other operational challenges thereby not respecting the original design inputs. Since trains do not run sufficiently and do not achieve the designed mileage within the specified time, car builder has a risk of not achieving the contractual MDBF target. This paper proposes a constant failure rate based model to deal with the situations where mileage accumulation is not a part of the design mission profile. The model provides appropriate MDBF target to be demonstrated based on actual accumulated mileage. A case study of rolling stock running in the field is undertaken to analyze the failure data and MDBF target demonstration during low mileage accumulation. The results of case study prove that with the proposed method, reliability targets are achieved under low mileage accumulation.

Keywords: mean distance between failures, mileage-based reliability, reliability target appropriations, rolling stock reliability

Procedia PDF Downloads 255
731 Effect of Humic Substance on Ex-Vitro Propagation of Saffron (Crocus Sativus L.)

Authors: Abdelghani Tahiri, Youssef Karra, Naima Ait Aabd, Abdelaziz Mimouni

Abstract:

Saffron (Crocus sativus L.), the most expensive spice in the world derived from the stigmas, is an autumn-flowering and sterile triploid (2n=3x=24) geophyte species that belong to the Iridaceae family. This plant species is mainly propagated vegetatively through the formation of daughter corms from the mother one. Low multiplication rates of daughter corms under natural conditions, along with fungal contamination, significantly reduce the productivity and quality of saffron corms. The development of efficient and sustainable strategies for rapid and large-scale production of selected cultivars of saffron will be desired. For this, the main objective of this work is to improve the vegetative propagation of saffron under ex-vitro conditions. Preliminary results of the influence of increasing doses of humic substances (HS) on the growth and multiplication of corms under greenhouse conditions are evaluated. The obtained data shows that the effect of HS depends on the concentration used and the mode of application. Indeed, the application through irrigation has increased the number of shoots and corms, but it has reduced other parameters. On the other hand, the temporary treatment has improved all observed parameters except for the number of shoots and corms. Results obtained in this work suggest that it is possible to improve the propagation of saffron corms under greenhouse conditions.

Keywords: saffron, Crocus sativus L., corm, humic substances

Procedia PDF Downloads 203
730 The Role of the Stud’s Configuration in the Structural Response of Composite Bridges

Authors: Mohammad Mahdi Mohammadi Dehnavi, Alessandra De Angelis, Maria Rosaria Pecce

Abstract:

This paper deals with the role of studs in the structural response of steel-concrete composite beams. A tri-linear slip-shear strength law is assumed according to literature and codes provisions for developing a finite element (FE) model of a case study of a composite deck. The variation of the strength and ductility of the connection is implemented in the numerical model carrying out nonlinear analyses. The results confirm the utility of the model to evaluate the importance of the studs capacity, ductility and strength on the global response (ductility and strength) of the structures but also to analyze the trend of slip and shear at interface along the beams.

Keywords: stud connectors, finite element method, slip, shear load, steel-concrete composite bridge

Procedia PDF Downloads 135
729 Vibration of a Beam on an Elastic Foundation Using the Variational Iteration Method

Authors: Desmond Adair, Kairat Ismailov, Martin Jaeger

Abstract:

Modelling of Timoshenko beams on elastic foundations has been widely used in the analysis of buildings, geotechnical problems, and, railway and aerospace structures. For the elastic foundation, the most widely used models are one-parameter mechanical models or two-parameter models to include continuity and cohesion of typical foundations, with the two-parameter usually considered the better of the two. Knowledge of free vibration characteristics of beams on an elastic foundation is considered necessary for optimal design solutions in many engineering applications, and in this work, the efficient and accurate variational iteration method is developed and used to calculate natural frequencies of a Timoshenko beam on a two-parameter foundation. The variational iteration method is a technique capable of dealing with some linear and non-linear problems in an easy and efficient way. The calculations are compared with those using a finite-element method and other analytical solutions, and it is shown that the results are accurate and are obtained efficiently. It is found that the effect of the presence of the two-parameter foundation is to increase the beam’s natural frequencies and this is thought to be because of the shear-layer stiffness, which has an effect on the elastic stiffness. By setting the two-parameter model’s stiffness parameter to zero, it is possible to obtain a one-parameter foundation model, and so, comparison between the two foundation models is also made.

Keywords: Timoshenko beam, variational iteration method, two-parameter elastic foundation model

Procedia PDF Downloads 183
728 Numerical Modelling and Soil-structure Interaction Analysis of Rigid Ballast-less and Flexible Ballast-based High-speed Rail Track-embankments Using Software

Authors: Tokirhusen Iqbalbhai Shaikh, M. V. Shah

Abstract:

With an increase in travel demand and a reduction in travel time, high-speed rail (HSR) has been introduced in India. Simplified 3-D finite element modelling is necessary to predict the stability and deformation characteristics of railway embankments and soil structure interaction behaviour under high-speed design requirements for Indian soil conditions. The objective of this study is to analyse the rigid ballast-less and flexible ballast-based high speed rail track embankments for various critical conditions subjected to them, viz. static condition, moving train condition, sudden brake application, and derailment case, using software. The input parameters for the analysis are soil type, thickness of the relevant strata, unit weight, Young’s modulus, Poisson’s ratio, undrained cohesion, friction angle, dilatancy angle, modulus of subgrade reaction, design speed, and other anticipated, relevant data. Eurocode 1, IRS-004(D), IS 1343, IRS specifications, California high-speed rail technical specifications, and the NHSRCL feasibility report will be followed in this study.

Keywords: soil structure interaction, high speed rail, numerical modelling, PLAXIS3D

Procedia PDF Downloads 100
727 The Synopsis of the AI-Powered Therapy Web Platform ‘Free AI Therapist'

Authors: Arwa Alnowaiser, Hala Shoukri

Abstract:

The ‘FreeAITherapist’ is an artificial intelligence application that uses the power of AI to offer advice and mental health counseling to its users through its chatbot services. The AI therapist is designed to understand users' issues, concerns, and problems and respond appropriately; it provides empathy and guidance and uses evidence-based therapeutic techniques. With its user-friendly platform, it ensures accessibility for individuals in need, regardless of their geographical location. This website was created in direct response to the growing demand for mental health support, aiming to provide a cost-effective and confidential solution. Through promising confidentiality, it considers user privacy and data security. The ‘FreeAITherapist’ strives to bridge the gap in mental health services, offering a reliable resource for individuals seeking guidance and counseling to improve their overall well-being.

Keywords: artificial intelligence, mental health, AI therapist, website, counseling

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726 Arteriosclerosis and Periodontitis: Correlation Expressed in the Amount of Fibrinogen in Blood

Authors: Nevila Alliu, Saimir Heta, Ilma Robo, Vera Ostreni

Abstract:

Periodontitis as an oral pathology caused by specific bacterial flora functions as a focal infection for the onset and aggravation of arteriosclerosis. These two distant pathologies, since they affect organs at a distance from each other, communicate with each other with correlation at the level of markers of inflammation in the blood. Fluctuations in the level of fibrinogen in the blood, depending on the active or passive phase of the existing periodontitis, affect the promotion of arteriosclerosis. The study is of the review type to analyze the effect of non-surgical periodontal treatment on fluctuations in the level of fibrinogen in the blood. The reduction of fibrinogen levels in the blood after non-surgical periodontal treatment of periodontitis in the patient's cavity is visible data and supported by literature sources. Also, the influence of a high amount of fibrinogen in the blood on the occurrence of arteriosclerosis is also another important data that again relies on many sources of literature. Conclusions: Thromboembolism and arteriosclerosis, as risk factors expressed in clinical data, have temporary bacteremia in the blood, which can occur significantly and often between phases of non-surgical periodontal treatment of periodontitis, treatments performed with treatment phases and protocols of predetermined treatment. Arterial thromboembolism has a significant factor, such as high levels of fibrinogen in the blood, which are significantly reduced during the period of non-surgical periodontal treatment.

Keywords: fibrinogen, refractory periodontitis, atherosclerosis, non-surgical, periodontal treatment

Procedia PDF Downloads 92
725 Efficient Control of Brushless DC Motors with Pulse Width Modulation

Authors: S. Shahzadi, J. Rizk

Abstract:

This paper describes the pulse width modulated control of a three phase, 4 polar DC brushless motor. To implement this practically the Atmel’s AVR ATmega 328 microcontroller embedded on an Arduino Eleven board is utilized. The microcontroller programming is done in an open source Arduino IDE development environment. The programming logic effectively manipulated a six MOSFET bridge which was used to energize the stator windings as per control requirements. The results obtained showed accurate, precise and efficient pulse width modulated operation. Another advantage offered by this pulse width modulated control was the efficient speed control of the motor. By varying the time intervals between successive commutations, faster energizing of the stator windings was possible thereby leading to quicker rotor alignment with these energized phases and faster revolutions.

Keywords: brushless DC motors, commutation, MOSFET, PWM

Procedia PDF Downloads 499
724 Role-Specific Target-Systems in Professional Bureaucracies: A Qualitative Analysis in the OR

Authors: Kirsten Hoeper, Maike Kriependorf

Abstract:

This paper firstly discusses the initial situation and problems. Afterward, it defines professional bureaucracies and shows their impact for the OR-work. The OR-center and its actors are shown. Finally, the paper provides the empiric design for detecting the target systems of the different work groups within the OR, the quality criteria in qualitative research and empirical results. It is shown that different groups have different targets in their daily work and that helps for a better understanding. More precisely, by detecting the target systems of these experts, we can ‘bridge’ the different points of view to create a common basis for the work in the OR. One of the aims was to find bridges to overcome separating factors. This paper describes the situation in Germany focusing the Hannover Medical School. It can be assumed that the results can be transferred to other countries using the DRG-System (Diagnosis Related Groups).

Keywords: hospital, OR, professional bureaucracies, target systems

Procedia PDF Downloads 286
723 Testicular Dose and Associated Risk from Common Pelvis Radiation Therapy in Iran

Authors: Ahmad Shanei, Milad Baradaran-Ghahfarokhi

Abstract:

This study aimed to investigate testicular dose (TD) and the associated risk of heritable disease from common pelvis radiotherapy of male patients in Iran. In this work, the relation between TD and changes in beam energy, pelvis size, source to skin distance (SSD) and beam directions (anterior or posterior) were also evaluated. The values of TDs were measured on 67 randomly selected male patients during common pelvis radiotherapy using 1.17 and 1.33 MeV, Theratron Cobalt-60 unit at SSD of 80 cm and 9 MV, Neptun 10 PC and 18 MV, GE Saturne 20 at SSD of 100 cm at Seyed-Al Shohada Hospital, Isfahan, Iran. Results showed that the maximum TD was up to 12% of the tumor dose. Considering the risk factor for radiation-induced heritable disorders of 0.1% per Sv, an excess risk of hereditary disorders of 72 per 10000 births was conservatively calculated. There was a significant difference in the measured TD using different treatment machines and energies (P < 0.001). The TD at 100 cm SSD were much less than that for 80 cm SSD (P <0.001). The Pearson Correlation test showed that, as expected, there was a strong correlation between TD and patient’s pelvis size (r = 0.275, P <0.001). Using the student’s t-tests, it was found that, there was not a significant difference between TD and beam direction (P = 0.231). Iranian male patients undergoing pelvic radiotherapy have the potential of receiving a TD of more than 1 Gy which might result in temporary azoospermia. The risk for induction of hereditary disorders in future generations should be considered as low but not negligible in comparison with the correspondent nominal risk.

Keywords: pelvis radiotherapy, testicular dose, infertility, hereditary effects

Procedia PDF Downloads 535
722 Using Machine Learning to Enhance Win Ratio for College Ice Hockey Teams

Authors: Sadixa Sanjel, Ahmed Sadek, Naseef Mansoor, Zelalem Denekew

Abstract:

Collegiate ice hockey (NCAA) sports analytics is different from the national level hockey (NHL). We apply and compare multiple machine learning models such as Linear Regression, Random Forest, and Neural Networks to predict the win ratio for a team based on their statistics. Data exploration helps determine which statistics are most useful in increasing the win ratio, which would be beneficial to coaches and team managers. We ran experiments to select the best model and chose Random Forest as the best performing. We conclude with how to bridge the gap between the college and national levels of sports analytics and the use of machine learning to enhance team performance despite not having a lot of metrics or budget for automatic tracking.

Keywords: NCAA, NHL, sports analytics, random forest, regression, neural networks, game predictions

Procedia PDF Downloads 104
721 Enhancement of Pool Boiling Regimes by Sand Deposition

Authors: G. Mazor, I. Ladizhensky, A. Shapiro, D. Nemirovsky

Abstract:

A lot of researches was dedicated to the evaluation of the efficiency of the uniform constant and temporary coatings enhancing a heat transfer rate. Our goal is an investigation of the sand coatings distributed by both uniform and non-uniform forms. The sand of different sizes (0.2-0.4-0.6 mm) was attached to a copper ball (30 mm diameter) surface by means of PVA adhesive as a uniform layer. At the next stage, sand spots were distributed over the ball surface with an areal density that ranges between one spot per 1.18 cm² (for low-density spots) and one spot per 0.51 cm² (for high-density spots). The spot's diameter value varied from 3 to 6.5 mm and height from 0.5 to 1.5 mm. All coatings serve as a heat transfer enhancer during the quenching in liquid nitrogen. Highest heat flux densities, achieved during quenching, lie in the range 10.8-20.2 W/cm², depending on the sand layer structure. Application of the enhancing coating increases an amount of heat, evacuated by highly effective nucleate and transition boiling, by a factor of 4.5 as compared to the bare sample. The non-uniform sand coatings were increasing the heat transfer rate value under all pool boiling conditions: nucleate boiling, transfer boiling and the most severe film boiling. A combination of uniform sand coating together with high-density sand spots increased the average heat transfer rate by a factor of 3.

Keywords: heat transfer enhancement, nucleate boiling, film boiling, transfer boiling

Procedia PDF Downloads 119
720 Building Information Models Utilization for Design Improvement of Infrastructure

Authors: Keisuke Fujioka, Yuta Itoh, Masaru Minagawa, Shunji Kusayanagi

Abstract:

In this study, building information models of the underground temporary structures and adjacent embedded pipes were constructed to show the importance of the information on underground pipes adjacent to the structures to enhance the productivity of execution of construction. Next, the bar chart used in actual construction process were employed to make the Gantt chart, and the critical pass analysis was carried out to show that accurate information on the arrangement of underground existing pipes can be used for the enhancement of the productivity of the construction of underground structures. In the analyzed project, significant construction delay was not caused by unforeseeable existence of underground pipes by the management ability of the construction manager. However, in many cases of construction executions in the developing countries, the existence of unforeseeable embedded pipes often causes substantial delay of construction. Design change based on uncertainty on the position information of embedded pipe can be also important risk for contractors in domestic construction. So CPM analyses were performed by a project-management-software to the situation that influence of the tasks causing construction delay was assumed more significant. Through the analyses, the efficiency of information management on underground pipes and BIM analysis in the design stage for workability improvement was indirectly confirmed.

Keywords: building-information modelling, construction information modelling, design improvement, infrastructure

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719 A Conceptual Framework of Digital Twin for Homecare

Authors: Raja Omman Zafar, Yves Rybarczyk, Johan Borg

Abstract:

This article proposes a conceptual framework for the application of digital twin technology in home care. The main goal is to bridge the gap between advanced digital twin concepts and their practical implementation in home care. This study uses a literature review and thematic analysis approach to synthesize existing knowledge and proposes a structured framework suitable for homecare applications. The proposed framework integrates key components such as IoT sensors, data-driven models, cloud computing, and user interface design, highlighting the importance of personalized and predictive homecare solutions. This framework can significantly improve the efficiency, accuracy, and reliability of homecare services. It paves the way for the implementation of digital twins in home care, promoting real-time monitoring, early intervention, and better outcomes.

Keywords: digital twin, homecare, older adults, healthcare, IoT, artificial intelligence

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718 Experimental Model for Instruction of Pre-Service Teachers in ICT Tools and E-Learning Environments

Authors: Rachel Baruch

Abstract:

This article describes the implementation of an experimental model for teaching ICT tools and digital environments in teachers training college. In most educational systems in the Western world, new programs were developed in order to bridge the digital gap between teachers and students. In spite of their achievements, these programs are limited due to several factors: The teachers in the schools implement new methods incorporating technological tools into the curriculum, but meanwhile the technology changes and advances. The interface of tools changes frequently, some tools disappear and new ones are invented. These conditions require an experimental model of training the pre-service teachers. The appropriate method for instruction within the domain of ICT tools should be based on exposing the learners to innovations, helping them to gain experience, teaching them how to deal with challenges and difficulties on their own, and training them. This study suggests some principles for this approach and describes step by step the implementation of this model.

Keywords: ICT tools, e-learning, pre-service teachers, new model

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717 Flexural Strength of Alkali Resistant Glass Textile Reinforced Concrete Beam with Prestressing

Authors: Jongho Park, Taekyun Kim, Jungbhin You, Sungnam Hong, Sun-Kyu Park

Abstract:

Due to the aging of bridges, increasing of maintenance costs and decreasing of structural safety is occurred. The steel corrosion of reinforced concrete bridge is the most common problem and this phenomenon is accelerating due to abnormal weather and increasing CO2 concentration due to climate change. To solve these problems, composite members using textile have been studied. A textile reinforced concrete can reduce carbon emissions by reduced concrete and without steel bars, so a lot of structural behavior studies are needed. Therefore, in this study, textile reinforced concrete beam was made and flexural test was performed. Also, the change of flexural strength according to the prestressing was conducted. As a result, flexural strength of TRC with prestressing was increased compared and flexural behavior was shown as reinforced concrete.

Keywords: AR-glass, flexural strength, prestressing, textile reinforced concrete

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716 An Analytical Study of the Concept of Emptiness Doctrine and Its Connection with Dependent Origination

Authors: Sanjoy Barua Chowdhury

Abstract:

The aim of this paper is an attempt to analyze the concept of emptiness from the early Buddhist teachings to subsequent Buddhist developmental schools, namely, Madhyamaka and Yogācāra Schools, along with attempting to examine an insightful bridge between the Buddha’s major teaching on dependent origination and the notion of emptiness. The initial part of this qualitative research focuses on the etymological term of emptiness (śūnyatā) and the Buddha’s teaching of emptiness from the Early Buddhist standpoint. Next, this research will seek to explain the concept of emptiness in the Madhyamaka School and Yogācāra School. This study further demonstrates the eradication of suffering is meant of understanding the concept emptiness from an ultimate standpoint with special concerning to focus the connection to the Buddha’s central teaching Dependent Origination.

Keywords: emptiness, Madhyamaka, dependent origination, early Buddhism, Yogacara

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715 The Impact of Major Accounting Events on Managerial Ability and the Accuracy of Environmental Capital Expenditure Projections of the Environmentally Sensitive Industries

Authors: Jason Chen, Jennifer Chen, Shiyu Li

Abstract:

We examine whether managerial ability (MA), the passing of Sarbanes-Oxley in 2002 (SOX), and corporate operational complexity affect the accuracy of environmental capital expenditure projections of the environmentally sensitive industries (ESI). Prior studies found that firms in the ESI manipulated their projected environmental capital expenditures as a tool to achieve corporate legitimation and suggested that human factors must be examined to determine whether they are part of the determinants. We use MA to proxy for the latent human factors to examine whether MA affects the accuracy of financial disclosures in the ESI. To expand Chen and Chen (2020), we further investigate whether (1) SOX and (2) firms with complex operations and financial reporting in conjunction with MA affect firms’ projection accuracy. We find, overall, that MA is positively correlated with firm’s projection accuracy in the annual 10-Ks. Furthermore, results suggest that SOX has a positive, yet temporary, effect on MA, and that leads to better accuracy. Finally, MA matters for firms with more complex operations and financial reporting to make less projection errors than their less-complex counterparts. These results suggest that MA is a determinant that affects the accuracy of environmental capital expenditure projections for the firms in the ESI.

Keywords: managerial ability, environmentally sensitive industries, sox, corporate operational complexity

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714 Assessment of Land Use and Land Cover Change in Lake Ol Bolossat Catchment, Nyandarua County, Kenya

Authors: John Wangui, Charles Gachene, Stephen Mureithi, Boniface Kiteme

Abstract:

Land use changes caused by demographic, natural variability, economic, technological and policy factors affect the goods and services derived from an ecosystem. In the past few decades, Lake Ol Bolossat catchment in Nyandarua County Kenya has been facing challenges of land cover changes threatening its capacity to perform ecosystems functions and adversely affecting communities and ecosystems downstream. This study assessed land cover changes in the catchment for a period of twenty eight years (from 1986 to 2014). Analysis of three Landsat images i.e. L5 TM 1986, L5 TM 1995 and L8 OLI/TIRS 2014 was done using ERDAS 9.2 software. The results show that dense forest, cropland and area under water increased by 27%, 29% and 3% respectively. On the other hand, open forest, dense grassland, open grassland, bushland and shrubland decreased by 3%, 3%, 11%, 26% and 1% respectively during the period under assessment. The lake was noted to have increased due to siltation caused by soil erosion causing a reduction in Lake’s depth and consequently causing temporary flooding of the wetland. The study concludes that the catchment is under high demographic pressure which would lead to resource use conflicts and therefore formulation of mitigation measures is highly recommended.

Keywords: land cover, land use change, land degradation, Nyandarua, Remote sensing

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713 Augmenting Navigational Aids: The Development of an Assistive Maritime Navigation Application

Authors: A. Mihoc, K. Cater

Abstract:

On the bridge of a ship the officers are looking for visual aids to guide navigation in order to reconcile the outside world with the position communicated by the digital navigation system. Aids to navigation include: Lighthouses, lightships, sector lights, beacons, buoys, and others. They are designed to help navigators calculate their position, establish their course or avoid dangers. In poor visibility and dense traffic areas, it can be very difficult to identify these critical aids to guide navigation. The paper presents the usage of Augmented Reality (AR) as a means to present digital information about these aids to support navigation. To date, nautical navigation related mobile AR applications have been limited to the leisure industry. If proved viable, this prototype can facilitate the creation of other similar applications that could help commercial officers with navigation. While adopting a user centered design approach, the team has developed the prototype based on insights from initial research carried on board of several ships. The prototype, built on Nexus 9 tablet and Wikitude, features a head-up display of the navigational aids (lights) in the area, presented in AR and a bird’s eye view mode presented on a simplified map. The application employs the aids to navigation data managed by Hydrographic Offices and the tablet’s sensors: GPS, gyroscope, accelerometer, compass and camera. Sea trials on board of a Navy and a commercial ship revealed the end-users’ interest in using the application and further possibility of other data to be presented in AR. The application calculates the GPS position of the ship, the bearing and distance to the navigational aids; all within a high level of accuracy. However, during testing several issues were highlighted which need to be resolved as the prototype is developed further. The prototype stretched the capabilities of Wikitude, loading over 500 objects during tests in a major port. This overloaded the display and required over 45 seconds to load the data. Therefore, extra filters for the navigational aids are being considered in order to declutter the screen. At night, the camera is not powerful enough to distinguish all the lights in the area. Also, magnetic interference with the bridge of the ship generated a continuous compass error of the AR display that varied between 5 and 12 degrees. The deviation of the compass was consistent over the whole testing durations so the team is now looking at the possibility of allowing users to manually calibrate the compass. It is expected that for the usage of AR in professional maritime contexts, further development of existing AR tools and hardware is needed. Designers will also need to implement a user-centered design approach in order to create better interfaces and display technologies for enhanced solutions to aid navigation.

Keywords: compass error, GPS, maritime navigation, mobile augmented reality

Procedia PDF Downloads 319
712 MPC of Single Phase Inverter for PV System

Authors: Irtaza M. Syed, Kaamran Raahemifar

Abstract:

This paper presents a model predictive control (MPC) of a utility interactive (UI) single phase inverter (SPI) for a photovoltaic (PV) system at residential/distribution level. The proposed model uses single-phase phase locked loop (PLL) to synchronize SPI with the grid and performs MPC control in a dq reference frame. SPI model consists of boost converter (BC), maximum power point tracking (MPPT) control, and a full bridge (FB) voltage source inverter (VSI). No PI regulators to tune and carrier and modulating waves are required to produce switching sequence. Instead, the operational model of VSI is used to synthesize sinusoidal current and track the reference. Model is validated using a three kW PV system at the input of UI-SPI in Matlab/Simulink. Implementation and results demonstrate simplicity and accuracy, as well as reliability of the model.

Keywords: phase locked loop, voltage source inverter, single phase inverter, model predictive control, Matlab/Simulink

Procedia PDF Downloads 519
711 Calibration of Hybrid Model and Arbitrage-Free Implied Volatility Surface

Authors: Kun Huang

Abstract:

This paper investigates whether the combination of local and stochastic volatility models can be calibrated exactly to any arbitrage-free implied volatility surface of European option. The risk neutral Brownian Bridge density is applied for calibration of the leverage function of our Hybrid model. Furthermore, the tails of marginal risk neutral density are generated by Generalized Extreme Value distribution in order to capture the properties of asset returns. The local volatility is generated from the arbitrage-free implied volatility surface using stochastic volatility inspired parameterization.

Keywords: arbitrage free implied volatility, calibration, extreme value distribution, hybrid model, local volatility, risk-neutral density, stochastic volatility

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710 Unicellular to Multicellular: Some Empirically Parsimoniously Plausible Hypotheses

Authors: Catherine K. Derow

Abstract:

Possibly a slime mold somehow mutated or already was mutated at progeniture and so stayed as a metazoan when it developed into the fruiting stage and so the slime mold(s) we are evolved and similar to are genetically differ from the slime molds in existence now. This may be why there are genetic links between humans and other metazoa now alive and slime molds now alive but we are now divergent branches of the evolutionary tree compared to the original slime mold, or perhaps slime mold-like organisms, that gave rise to metazoan animalia and perhaps algae and plantae as slime molds were undifferentiated enough in many ways that could allow their descendants to evolve into these three separate phylogenetic categories. Or it may be a slime mold was born or somehow progenated as multicellular, as the particular organism was mutated enough to have say divided in a a 'pseudo-embryonic' stage, and this could have happened for algae, plantae as well as animalia or all the branches may be from the same line but the missing link might be covered in 'phylogenetic sequence comparison noise'.

Keywords: metazoan evolution, unicellular bridge to metazoans, evolution, slime mold

Procedia PDF Downloads 216
709 A Milky-White Stream Water Suitability for Drinking Purpose

Authors: Kassahun Tadesse, Megersa O. Dinka

Abstract:

Drinking water suitability study was conducted for a milky-white stream in remote areas of Ethiopia in order to understand its effect on human health. Water samples were taken from the water source and physicochemical properties were analyzed based on standard methods. The mean values of pH, total dissolved solids, sodium, magnesium, potassium, manganese, chloride, boron, and fluoride were within maximum permissible limits set for health. Whereas turbidity, calcium, irons, hardness, alkalinity, nitrate, and sulfate contents were above the limits. The water is very hard water due to high calcium content. High sulfate content can cause noticeable taste and a laxative (gastrointestinal) effect. The nitrate content was very high and can cause methemoglobinemia (blue baby syndrome) which is a temporary blood disorder in the bottle fed infants. Hence, parents should be advised not to give this water to infants. In conclusion, all physicochemical parameters except for nitrate are safe for health but may affect the appearance and taste, and wear water infrastructures. A high value of turbidity due to suspended minerals is the cause for milky-white colour. However, a mineralogical analysis of suspended sediments is required to identify the exact cause for white colour, and a study on sediment source was recommended.

Keywords: hard water, laxative effect, methemoglobinemia, nitrate, physicochemical, water quality

Procedia PDF Downloads 184
708 Methodology: A Review in Modelling and Predictability of Embankment in Soft Ground

Authors: Bhim Kumar Dahal

Abstract:

Transportation network development in the developing country is in rapid pace. The majority of the network belongs to railway and expressway which passes through diverse topography, landform and geological conditions despite the avoidance principle during route selection. Construction of such networks demand many low to high embankment which required improvement in the foundation soil. This paper is mainly focused on the various advanced ground improvement techniques used to improve the soft soil, modelling approach and its predictability for embankments construction. The ground improvement techniques can be broadly classified in to three groups i.e. densification group, drainage and consolidation group and reinforcement group which are discussed with some case studies.  Various methods were used in modelling of the embankments from simple 1-dimensional to complex 3-dimensional model using variety of constitutive models. However, the reliability of the predictions is not found systematically improved with the level of sophistication.  And sometimes the predictions are deviated more than 60% to the monitored value besides using same level of erudition. This deviation is found mainly due to the selection of constitutive model, assumptions made during different stages, deviation in the selection of model parameters and simplification during physical modelling of the ground condition. This deviation can be reduced by using optimization process, optimization tools and sensitivity analysis of the model parameters which will guide to select the appropriate model parameters.

Keywords: cement, improvement, physical properties, strength

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707 Role of Sequestration of CO2 Due to the Carbonation in Total CO2 Emission Balance in Concrete Life

Authors: P. P. Woyciechowski

Abstract:

Calculation of the carbon footprint of cement concrete is a complex process including consideration of the phase of primary life (components and concrete production processes, transportation, construction works, maintenance of concrete structures) and secondary life, including demolition and recycling. Taking into consideration the effect of concrete carbonation can lead to a reduction in the calculated carbon footprint of concrete. In this paper, an example of CO2 balance for small bridge elements made of Portland cement reinforced concrete was done. The results include the effect of carbonation of concrete in a structure and of concrete rubble after demolition. It was shown that important impact of carbonation on the balance is possible only when rubble carbonation is possible. It was related to the fact that only the sequestration potential in the secondary phase of concrete life has significant value.

Keywords: carbon footprint, balance of carbon dioxide in nature, concrete carbonation, the sequestration potential of concrete

Procedia PDF Downloads 217