Search results for: dynamic database
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5495

Search results for: dynamic database

5165 Descriptive Analysis of the Database of Poliomyelitis Surveillance System in Mauritania from 2012-2019

Authors: B. Baba Ahmed, P. Yanogo, B. Djibryl. N. Medas

Abstract:

Introduction: Polio is a highly contagious viral infection, with children under 5 years of age being the most affected. It is a public health emergency of international concern. Polio surveillance in Mauritania has been ongoing since 1998 and has achieved "polio free" status in 2007. our objective is to analyse a pidemiological surveillance database of poliomyélitis in Mauritania from 2012-2019. Method: A transversal descriptive analysis of poliomyélitis database was carried out in Mauritania from 2012-2019.An exhaustive sampling was done on all suspected polio cases recorded in the database from 2012 -2019. This study used EPI-INFO 7.4 for frequency calculation for qualitative variables, mean and standard deviation for quantitative variables. Results: We found 459 suspected cases of polio over the study period with an average rate of acute non-polio flaccid paralysis of 25.4 cases/100,000 children under 15 years of age. The age group 0-6 years represented 75.2%. Males constituted 50.2%. Females represented 49.78% with a ratio of M/F=1.Among the 422 observations, the average age is 4 years +/- 3.38. The four regions, TIRIS-ZEMMOUR, INCHIRI, TAGANT, NOUACHCHOTT OUEST recorded the lowest percentages of notifications, respectively (3.28%; 3.93%; 4.37%; 4.8%). 99.34% [98.09-99.78] of cases presented acute flaccid paralysis. And 56.77% [52.19-61.23], had limb asymmetry. We showed that 82.93% [79.21-86.10], had fever. we found that 89.5% of suspected polio cases were investigated before 48 hours. And 88.39% of suspected cases had two adequate samples taken 48 hours apart and within 14 days after the onset of symptoms. Only 30.95% of samples arrived at the referral laboratory before 72 hours. Conclusion: This study has shown that Mauritania has achieved the objectives in most of the quantitative performance indicators of polio surveillance. This study has shown a low notification of cases in the northern and central regions of the country. There is a problem with the transport of samples to the laboratory.

Keywords: analysis, data base, Epi-Info, polio

Procedia PDF Downloads 175
5164 Optimization of Tolerance Grades of a Bearing and Shaft Assembly in a Washing Machine with Regard to Fatigue Life

Authors: M. Cangi, T. Dolar, C. Ersoy, Y. E. Aydogdu, A. I. Aydeniz, A. Mugan

Abstract:

The drum is one of the critical parts in a washing machine in which the clothes are washed and spin by the rotational movement. It is activated by the drum shaft which is attached to an electric motor and subjected to dynamic loading. Being one of the critical components, failures of the drum require costly repairs of dynamic components. In this study, tolerance bands between the drum shaft and its two bearings were examined to develop a relationship between the fatigue life of the shaft and the interaction tolerances. Optimization of tolerance bands was completed in consideration of the fatigue life of the shaft as the cost function. The following methodology is followed: multibody dynamic model of a washing machine was constructed and used to calculate dynamic loading on the components. Then, these forces were used in finite element analyses to calculate the stress field in critical components which was used for fatigue life predictions. The factors affecting the fatigue life were examined to find optimum tolerance grade for a given test condition. Numerical results were verified by experimental observations.

Keywords: fatigue life, finite element analysis, tolerance analysis, optimization

Procedia PDF Downloads 157
5163 On the Design of a Secure Two-Party Authentication Scheme for Internet of Things Using Cancelable Biometrics and Physically Unclonable Functions

Authors: Behnam Zahednejad, Saeed Kosari

Abstract:

Widespread deployment of Internet of Things (IoT) has raised security and privacy issues in this environment. Designing a secure two-factor authentication scheme between the user and server is still a challenging task. In this paper, we focus on Cancelable Biometric (CB) as an authentication factor in IoT. We show that previous CB-based scheme fail to provide real two-factor security, Perfect Forward Secrecy (PFS) and suffer database attacks and traceability of the user. Then we propose our improved scheme based on CB and Physically Unclonable Functions (PUF), which can provide real two-factor security, PFS, user’s unlinkability, and resistance to database attack. In addition, Key Compromise Impersonation (KCI) resilience is achieved in our scheme. We also prove the security of our proposed scheme formally using both Real-Or-Random (RoR) model and the ProVerif analysis tool. For the usability of our scheme, we conducted a performance analysis and showed that our scheme has the least communication cost compared to the previous CB-based scheme. The computational cost of our scheme is also acceptable for the IoT environment.

Keywords: IoT, two-factor security, cancelable biometric, key compromise impersonation resilience, perfect forward secrecy, database attack, real-or-random model, ProVerif

Procedia PDF Downloads 102
5162 The Dynamic Cone Penetration Test: A Review of Its Correlations and Applications

Authors: Abdulrahman M. Hamid

Abstract:

Dynamic Cone Penetration Test (DCPT) is widely used for field quality assessment of soils. Its application to predict the engineering properties of soil is globally promoted by the fact that it is difficult to obtain undisturbed soil samples, especially when loose or submerged sandy soil is encountered. Detailed discussion will be presented on the current development of DCPT correlations with resilient modulus, relative density, California Bearing Ratio (CBR), unconfined compressive strength and shear strength that have been developed for different materials in both the laboratory and field, as well as on the usage of DCPT in quality control of compaction of earth fills and performance evaluation of pavement layers. In addition, the relationship of the DCPT with other instruments such as falling weight deflectometer, nuclear gauge, soil stiffens gauge, and plate load test will be reported. Lastely, the application of DCPT in Saudi Arabia in recent years will be addressed in this manuscript.

Keywords: dynamic cone penetration test, falling weight deflectometer, nuclear gauge, soil stiffens gauge, plate load test, automated dynamic cone penetration

Procedia PDF Downloads 433
5161 Dynamic Mechanical Thermal Properties of Arenga pinnata Fibre Reinforced Epoxy Composite: Effects of Alkaline Treatment

Authors: Abdul Hakim Abdullah, Mohamad Syafiq Abdul Khadir

Abstract:

In present investigations, thermal behaviours of Arenga pinnata fibres prior and after alkaline treatment were studied. The alkaline treatments were applied on the Arenga pinnata fibres by immersing in the alkaline solution, 6% sodium hydroxide (NaOH). Using hand lay-out technique, composites were fabricated at 20% and 40% by Arenga pinnata fibres weight contents. The thermal behaviours of both untreated and treated composites were determined by employing Dynamic Mechanical Analysis (DMA). The results show that the TAP owned better results of Storage Modulus (E’), Loss Modulus (E”) and Tan Delta temperatures ranges from 0°C to 60°C.

Keywords: composites, Arenga pinnata fibre, alkaline treatment, dynamic mechanical properties

Procedia PDF Downloads 360
5160 The Effect of AMBs Number of a Dynamics Behavior of a Spur Gear Reducer in Non-Stationary Regime

Authors: Najib Belhadj Messaoud, Slim Souissi

Abstract:

The non-linear dynamic behavior of a single stage spur gear reducer is studied in this paper in transient regime. Driving and driver rotors are, respectively, powered by a motor torque Cm and loaded by a resistive torque Cr. They are supported by two identical Active Magnetic Bearings (AMBs). Gear excitation is induced by the motor torque and load variation in addition to the fluctuation of meshing stiff-ness due to the variation of input rotational speed. Three models of AMBs were used with four, six and eight magnets. They are operated by P.D controller and powered by control and bias currents. The dynamic parameters of the AMBs are modeled by stiffness and damping matrices computed by the derivation of the electromagnetic forces. The equations of motion are solved iteratively using Newmark time integration method. In the first part of the study, the model is powered by an electric motor and by a four strokes four cylinders diesel engine in the second part. The numerical results of the dynamic responses of the system come to confirm the significant effect of the transient regime on the dynamic behavior of a gear set, particularly in the case of engine acyclism condition. Results also confirm the influence of the magnet number by AMBs on the dynamic behavior of the system. Indeed, vibrations were more important in the case of gear reducer supported by AMBs with four magnets.

Keywords: motor, stiffness, gear, acyclism, fluctuation, torque

Procedia PDF Downloads 459
5159 Analysis of Nonlinear and Non-Stationary Signal to Extract the Features Using Hilbert Huang Transform

Authors: A. N. Paithane, D. S. Bormane, S. D. Shirbahadurkar

Abstract:

It has been seen that emotion recognition is an important research topic in the field of Human and computer interface. A novel technique for Feature Extraction (FE) has been presented here, further a new method has been used for human emotion recognition which is based on HHT method. This method is feasible for analyzing the nonlinear and non-stationary signals. Each signal has been decomposed into the IMF using the EMD. These functions are used to extract the features using fission and fusion process. The decomposition technique which we adopt is a new technique for adaptively decomposing signals. In this perspective, we have reported here potential usefulness of EMD based techniques.We evaluated the algorithm on Augsburg University Database; the manually annotated database.

Keywords: intrinsic mode function (IMF), Hilbert-Huang transform (HHT), empirical mode decomposition (EMD), emotion detection, electrocardiogram (ECG)

Procedia PDF Downloads 580
5158 Modeling of Geotechnical Data Using GIS and Matlab for Eastern Ahmedabad City, Gujarat

Authors: Rahul Patel, S. P. Dave, M. V Shah

Abstract:

Ahmedabad is a rapidly growing city in western India that is experiencing significant urbanization and industrialization. With projections indicating that it will become a metropolitan city in the near future, various construction activities are taking place, making soil testing a crucial requirement before construction can commence. To achieve this, construction companies and contractors need to periodically conduct soil testing. This study focuses on the process of creating a spatial database that is digitally formatted and integrated with geotechnical data and a Geographic Information System (GIS). Building a comprehensive geotechnical Geo-database involves three essential steps. Firstly, borehole data is collected from reputable sources. Secondly, the accuracy and redundancy of the data are verified. Finally, the geotechnical information is standardized and organized for integration into the database. Once the Geo-database is complete, it is integrated with GIS. This integration allows users to visualize, analyze, and interpret geotechnical information spatially. Using a Topographic to Raster interpolation process in GIS, estimated values are assigned to all locations based on sampled geotechnical data values. The study area was contoured for SPT N-Values, Soil Classification, Φ-Values, and Bearing Capacity (T/m2). Various interpolation techniques were cross-validated to ensure information accuracy. The GIS map generated by this study enables the calculation of SPT N-Values, Φ-Values, and bearing capacities for different footing widths and various depths. This approach highlights the potential of GIS in providing an efficient solution to complex phenomena that would otherwise be tedious to achieve through other means. Not only does GIS offer greater accuracy, but it also generates valuable information that can be used as input for correlation analysis. Furthermore, this system serves as a decision support tool for geotechnical engineers. The information generated by this study can be utilized by engineers to make informed decisions during construction activities. For instance, they can use the data to optimize foundation designs and improve site selection. In conclusion, the rapid growth experienced by Ahmedabad requires extensive construction activities, necessitating soil testing. This study focused on the process of creating a comprehensive geotechnical database integrated with GIS. The database was developed by collecting borehole data from reputable sources, verifying its accuracy and redundancy, and organizing the information for integration. The GIS map generated by this study is an efficient solution that offers greater accuracy and generates valuable information that can be used as input for correlation analysis. It also serves as a decision support tool for geotechnical engineers, allowing them to make informed decisions during construction activities.

Keywords: arcGIS, borehole data, geographic information system (GIS), geo-database, interpolation, SPT N-value, soil classification, φ-value, bearing capacity

Procedia PDF Downloads 68
5157 Partner Selection in International Strategic Alliances: The Case of the Information Industry

Authors: H. Nakamura

Abstract:

This study analyzes international strategic alliances in the information industry. The purpose of this study is to clarify the strategic intention of an international alliance. Secondly, it investigates the influence of differences in the target markets of partner companies on alliances. Using an international strategy theory approach to analyze the global strategies of global companies, the study compares a database business and an electronic publishing business. In particular, these cases emphasized factors attributable to "people" and "learning", reliability and communication between organizations and the evolution of the IT infrastructure. The theory evolved in this study validates the effectiveness of these strategies.

Keywords: database business, electronic library, international strategic alliances, partner selection

Procedia PDF Downloads 372
5156 The Development of Chinese-English Homophonic Word Pairs Databases for English Teaching and Learning

Authors: Yuh-Jen Wu, Chun-Min Lin

Abstract:

Homophonic words are common in Mandarin Chinese which belongs to the tonal language family. Using homophonic cues to study foreign languages is one of the learning techniques of mnemonics that can aid the retention and retrieval of information in the human memory. When learning difficult foreign words, some learners transpose them with words in a language they are familiar with to build an association and strengthen working memory. These phonological clues are beneficial means for novice language learners. In the classroom, if mnemonic skills are used at the appropriate time in the instructional sequence, it may achieve their maximum effectiveness. For Chinese-speaking students, proper use of Chinese-English homophonic word pairs may help them learn difficult vocabulary. In this study, a database program is developed by employing Visual Basic. The database contains two corpora, one with Chinese lexical items and the other with English ones. The Chinese corpus contains 59,053 Chinese words that were collected by a web crawler. The pronunciations of this group of words are compared with words in an English corpus based on WordNet, a lexical database for the English language. Words in both databases with similar pronunciation chunks and batches are detected. A total of approximately 1,000 Chinese lexical items are located in the preliminary comparison. These homophonic word pairs can serve as a valuable tool to assist Chinese-speaking students in learning and memorizing new English vocabulary.

Keywords: Chinese, corpus, English, homophonic words, vocabulary

Procedia PDF Downloads 182
5155 The Effects of Dynamic Training Shoes Exercises on Isokinetic Strength Performance

Authors: Bergun Meric Bingul, Yezdan Cinel, Murat Son, Cigdem Bulgan, Mensure Aydin

Abstract:

The aim of this study was to determination of the effects of knee and hip isokinetic performance during the training with the special designed roller-shoes. 30 soccer players participated as subjects and these subjects were divided into 3 groups randomly. Training groups were; with the dynamic training shoes group, without the dynamic training shoes group and control group. Subjects were trained speed strength trainings during 8 weeks (3 days a week and 1 hour a day). 6 exercises were focused on the knee flexors and extensors, also hip adductor and abductor muscles were chosen and performed in 3x30secs at each sets. Control group was not paticipated to the training program. Before and after the training programs knee flexor and extensor muscles and hip abductor and adductor muscles’ peak torques were measured by Biodex III isokinetic dynamometer. Isokinetic strength data were analyzed by using SPSS program. A repeated measures analysis of variance (ANOVA) was used to determine differences among the peak torque values for three groups. The results indicated that soccer players’ peak torque values that the group of using the dynamic training shoes, were found higher. Also, hip adductor and abductor peak torques that the group of using the dynamic training shoes, were obtained better than the other groups. In conclusion, the ground friction forces are an important role of increasing strength. With these shoes, using rollers, soccer players were able to move easily because of the friction forces were reduced and created more range of motion. So, exercises were performed faster than before and strength movements in all angles, it ensured that the active state. This was resulted in a better use of force.

Keywords: isokinetic, soccer, dynamic training shoes, training

Procedia PDF Downloads 269
5154 Resource Sharing Issues of Distributed Systems Influences on Healthcare Sector Concurrent Environment

Authors: Soo Hong Da, Ng Zheng Yao, Burra Venkata Durga Kumar

Abstract:

The Healthcare sector is a business that consists of providing medical services, manufacturing medical equipment and drugs as well as providing medical insurance to the public. Most of the time, the data stored in the healthcare database is to be related to patient’s information which is required to be accurate when it is accessed by authorized stakeholders. In distributed systems, one important issue is concurrency in the system as it ensures the shared resources to be synchronized and remains consistent through multiple read and write operations by multiple clients. The problems of concurrency in the healthcare sector are who gets the access and how the shared data is synchronized and remains consistent when there are two or more stakeholders attempting to the shared data simultaneously. In this paper, a framework that is beneficial to distributed healthcare sector concurrent environment is proposed. In the proposed framework, four different level nodes of the database, which are national center, regional center, referral center, and local center are explained. Moreover, the frame synchronization is not symmetrical. There are two synchronization techniques, which are complete and partial synchronization operation are explained. Furthermore, when there are multiple clients accessed at the same time, synchronization types are also discussed with cases at different levels and priorities to ensure data is synchronized throughout the processes.

Keywords: resources, healthcare, concurrency, synchronization, stakeholders, database

Procedia PDF Downloads 149
5153 Reducing Hazardous Materials Releases from Railroad Freights through Dynamic Trip Plan Policy

Authors: Omar A. Abuobidalla, Mingyuan Chen, Satyaveer S. Chauhan

Abstract:

Railroad transportation of hazardous materials freights is important to the North America economics that supports the national’s supply chain. This paper introduces various extensions of the dynamic hazardous materials trip plan problems. The problem captures most of the operational features of a real-world railroad transportations systems that dynamically initiates a set of blocks and assigns each shipment to a single block path or multiple block paths. The dynamic hazardous materials trip plan policies have distinguishing features that are integrating the blocking plan, and the block activation decisions. We also present a non-linear mixed integer programming formulation for each variant and present managerial insights based on a hypothetical railroad network. The computation results reveal that the dynamic car scheduling policies are not only able to take advantage of the capacity of the network but also capable of diminishing the population, and environment risks by rerouting the active blocks along the least risky train services without sacrificing the cost advantage of the railroad. The empirical results of this research illustrate that the issue of integrating the blocking plan, and the train makeup of the hazardous materials freights must receive closer attentions.

Keywords: dynamic car scheduling, planning and scheduling hazardous materials freights, airborne hazardous materials, gaussian plume model, integrated blocking and routing plans, box model

Procedia PDF Downloads 205
5152 Multi-Atlas Segmentation Based on Dynamic Energy Model: Application to Brain MR Images

Authors: Jie Huo, Jonathan Wu

Abstract:

Segmentation of anatomical structures in medical images is essential for scientific inquiry into the complex relationships between biological structure and clinical diagnosis, treatment and assessment. As a method of incorporating the prior knowledge and the anatomical structure similarity between a target image and atlases, multi-atlas segmentation has been successfully applied in segmenting a variety of medical images, including the brain, cardiac, and abdominal images. The basic idea of multi-atlas segmentation is to transfer the labels in atlases to the coordinate of the target image by matching the target patch to the atlas patch in the neighborhood. However, this technique is limited by the pairwise registration between target image and atlases. In this paper, a novel multi-atlas segmentation approach is proposed by introducing a dynamic energy model. First, the target is mapped to each atlas image by minimizing the dynamic energy function, then the segmentation of target image is generated by weighted fusion based on the energy. The method is tested on MICCAI 2012 Multi-Atlas Labeling Challenge dataset which includes 20 target images and 15 atlases images. The paper also analyzes the influence of different parameters of the dynamic energy model on the segmentation accuracy and measures the dice coefficient by using different feature terms with the energy model. The highest mean dice coefficient obtained with the proposed method is 0.861, which is competitive compared with the recently published method.

Keywords: brain MRI segmentation, dynamic energy model, multi-atlas segmentation, energy minimization

Procedia PDF Downloads 336
5151 Dynamic Response and Damage Modeling of Glass Fiber Reinforced Epoxy Composite Pipes: Numerical Investigation

Authors: Ammar Maziz, Mostapha Tarfaoui, Said Rechak

Abstract:

The high mechanical performance of composite pipes can be adversely affected by their low resistance to impact loads. Loads in dynamic origin are dangerous and cause consequences on the operation of pipes because the damage is often not detected and can affect the structural integrity of composite pipes. In this work, an advanced 3-D finite element (FE) model, based on the use of intralaminar damage models was developed and used to predict damage under low-velocity impact. The performance of the numerical model is validated with the confrontation with the results of experimental tests. The results show that at low impact energy, the damage happens mainly by matrix cracking and delamination. The model capabilities to simulate the low-velocity impact events on the full-scale composite structures were proved.

Keywords: composite materials, low velocity impact, FEA, dynamic behavior, progressive damage modeling

Procedia PDF Downloads 172
5150 Decision Support System for Tourism in Northern Part of Thailand

Authors: Katejarinporn Chaiya, Thawit Janbanklong

Abstract:

The purposes of this study were to design and find users’ satisfaction after using the decision support system for tourism in the Northern part of Thailand, which can provide tourists with touristic information and plan their personal voyage. Such information can be retrieved systematically based on personal budget and provinces. The samples of this study were five experts and users: 30 "white collars" in Bangkok. This decision support system was designed via ASP.NET. Its database was developed by using MySQL, for administrators to effectively manage the database. The application outcome revealed that the innovation works properly as sought in objectives. Specialists and white collars in Bangkok have evaluated the decision support system; the result was satisfactorily positive.

Keywords: decision Support System, ASP.NET, MySQL, white collars

Procedia PDF Downloads 358
5149 A.T.O.M.- Artificial Intelligent Omnipresent Machine

Authors: R. Kanthavel, R. Yogesh Kumar, T. Narendrakumar, B. Santhosh, S. Surya Prakash

Abstract:

This paper primarily focuses on developing an affordable personal assistant and the implementation of it in the field of Artificial Intelligence (AI) to create a virtual assistant/friend. The problem in existing home automation techniques is that it requires the usage of exact command words present in the database to execute the corresponding task. Our proposed work is ATOM a.k.a ‘Artificial intelligence Talking Omnipresent Machine’. Our inspiration came from an unlikely source- the movie ‘Iron Man’ in which a character called J.A.R.V.I.S has omnipresence, and device controlling capability. This device can control household devices in real time and send the live information to the user. This device does not require the user to utter the exact commands specified in the database as it can capture the keywords from the uttered commands, correlates the obtained keywords and perform the specified task. This ability to compare and correlate the keywords gives the user the liberty to give commands which are not necessarily the exact words provided in the database. The proposed work has a higher flexibility (due to its keyword extracting ability from the user input) comparing to the existing work Intelligent Home automation System (IHAS), is more accurate, and is much more affordable as it makes use of WI-FI module and raspberry pi 2 instead of ZigBee and a computer respectively.

Keywords: home automation, speech recognition, voice control, personal assistant, artificial intelligence

Procedia PDF Downloads 336
5148 Bonding Characteristics Between FRP and Concrete Substrates

Authors: Houssam A. Toutanji, Meng Han

Abstract:

This study focuses on the development of a fracture mechanics based-model that predicts the debonding behavior of FRP strengthened RC beams. In this study, a database includes 351 concrete prisms bonded with FRP plates tested in single and double shear were prepared. The existing fracture-mechanics-based models are applied to this database. Unfortunately the properties of adhesive layer, especially a soft adhesive layer, used on the specimens in the existing studies were not always able to found. Thus, the new model’s proposal was based on fifteen newly conducted pullout tests and twenty four data selected from two independent existing studies with the application of a soft adhesive layers and the availability of adhesive properties.

Keywords: carbon fiber composite materials, interface response, fracture characteristics, maximum shear stress, ultimate transferable load

Procedia PDF Downloads 269
5147 Prevalence and Risk Factors of Economic Toxicity in Gynecologic Malignancies: A Systematic Review

Authors: Dongliu Li

Abstract:

Objective: This study systematically evaluates the incidence and influencing factors of economic toxicity in patients with gynecological malignant tumors. Methods: Literature on economic toxicity of gynecological malignancies were comprehensively searched in Pubmed, The Cochrane Library, Web of Science, Embase, CINAHL, CNKI, Wanfang Database, Chinese Biomedical Literature database and VIP database. The search period is up to February 2024. Stata 17 software was used to conduct a single-group meta-analysis of the incidence of economic toxicity in gynecological malignant tumors, and descriptive analysis was used to analyze the influencing factors. Results: A total of 11 pieces of literature were included, including 6475 patients with gynecological malignant tumors. The results of the meta-analysis showed that the incidence of economic toxicity in gynecological malignant tumors was 40% (95%CI 31%—48%). The influencing factors of economic toxicity in patients with gynecological malignant tumors include social demographic factors, medical insurance-related factors and disease-related factors. Conclusion: The incidence of economic toxicity in patients with gynecological malignant tumors is high, and medical staff should conduct early screening of patients according to relevant influencing factors, personalized assessment of patients' economic status, early prevention work and personalized intervention measures.

Keywords: gynecological malignancy, economic toxicity, the incidence rate, influencing factors, systematic review

Procedia PDF Downloads 30
5146 Chatter Prediction of Curved Thin-walled Parts Considering Variation of Dynamic Characteristics Based on Acoustic Signals Acquisition

Authors: Damous Mohamed, Zeroudi Nasredine

Abstract:

High-speed milling of thin-walled parts with complex curvilinear profiles often encounters machining instability, commonly referred to as chatter. This phenomenon arises due to the dynamic interaction between the cutting tool and the part, exacerbated by the part's low rigidity and varying dynamic characteristics along the tool path. This research presents a dynamic model specifically developed to predict machining stability for such curved thin-walled components. The model employs the semi-discretization method, segmenting the tool trajectory into small, straight elements to locally approximate the behavior of an inclined plane. Dynamic characteristics for each segment are extracted through experimental modal analysis and incorporated into the simulation model to generate global stability lobe diagrams. Validation of the model is conducted through cutting tests where acoustic intensity is measured to detect instabilities. The experimental data align closely with the predicted stability limits, confirming the model's accuracy and effectiveness. This work provides a comprehensive approach to enhancing machining stability predictions, thereby improving the efficiency and quality of high-speed milling operations for thin-walled parts.

Keywords: chatter, curved thin-walled part, semi-discretization method, stability lobe diagrams

Procedia PDF Downloads 26
5145 Effect of Design Parameters on Porpoising Instability of a High Speed Planing Craft

Authors: Lokeswara Rao P., Naga Venkata Rakesh N., V. Anantha Subramanian

Abstract:

It is important to estimate, predict, and avoid the dynamic instability of high speed planing crafts. It is known that design parameters like relative location of center of gravity with respect to the dynamic lift centre and length to beam ratio of the craft have influence on the tendency to porpoise. This paper analyzes the hydrodynamic performance on the basis of the semi-empirical Savitsky method and also estimates the same by numerical simulations based on Reynolds Averaged Navier Stokes (RANS) equations using a commercial code namely, STAR- CCM+. The paper examines through the same numerical simulation considering dynamic equilibrium, the changing running trim, which results in porpoising. Some interesting results emerge from the study and this leads to early detection of the instability.

Keywords: CFD, planing hull, porpoising, Savitsky method

Procedia PDF Downloads 179
5144 Fluid Structure Interaction of Offshore Concrete Columns under Explosion Loads

Authors: Ganga K. V. Prakhya, V. Karthigeyan

Abstract:

The paper describes the influences of the fluid and structure interaction in concrete structures that support large oil platforms in the North Sea. The dynamic interaction of the fluid both in 2D and 3D are demonstrated through a Computational Fluid Dynamics analysis in the event of explosion following a gas leak inside of the concrete column. The structural response characteristics of the column in water under dynamic conditions are quite complex involving axial, radial and circumferential modes. Fluid structure interaction (FSI) modelling showed that there are some frequencies of the column in water which are not found for a column in air. For example, it was demonstrated that one of the axial breathing modes can never be simulated without the use of FSI models. The occurrence of a shift in magnitude and time of pressure from explosion following gas leak along the height of the shaft not only excited the modes of vibration involving breathing (axial), bending and squashing (radial) modes but also magnified the forces in the column. FSI models revealed that dynamic effects resulted in dynamic amplification of loads. The results are summarized from a detailed study that was carried out by the first author for the Offshore Safety Division of Health & Safety Executive United Kingdom.

Keywords: concrete, explosion, fluid structure interaction, offshore structures

Procedia PDF Downloads 188
5143 Experimental Investigation of the Out-of-Plane Dynamic Behavior of Adhesively Bonded Composite Joints at High Strain Rates

Authors: Sonia Sassi, Mostapha Tarfaoui, Hamza Ben Yahia

Abstract:

In this investigation, an experimental technique in which the dynamic response, damage kinetic and heat dissipation are measured simultaneously during high strain rates on adhesively bonded joints materials. The material used in this study is widely used in the design of structures for military applications. It was composed of a 45° Bi-axial fiber-glass mat of 0.286 mm thickness in a Polyester resin matrix. In adhesive bonding, a NORPOL Polyvinylester of 1 mm thickness was used to assemble the composite substrate. The experimental setup consists of a compression Split Hopkinson Pressure Bar (SHPB), a high-speed infrared camera and a high-speed Fastcam rapid camera. For the dynamic compression tests, 13 mm x 13 mm x 9 mm samples for out-of-plane tests were considered from 372 to 1030 s-1. Specimen surface is controlled and monitored in situ and in real time using the high-speed camera which acquires the damage progressive in specimens and with the infrared camera which provides thermal images in time sequence. Preliminary compressive stress-strain vs. strain rates data obtained show that the dynamic material strength increases with increasing strain rates. Damage investigations have revealed that the failure mainly occurred in the adhesive/adherent interface because of the brittle nature of the polymeric adhesive. Results have shown the dependency of the dynamic parameters on strain rates. Significant temperature rise was observed in dynamic compression tests. Experimental results show that the temperature change depending on the strain rate and the damage mode and their maximum exceed 100 °C. The dependence of these results on strain rate indicates that there exists a strong correlation between damage rate sensitivity and heat dissipation, which might be useful when developing damage models under dynamic loading tacking into account the effect of the energy balance of adhesively bonded joints.

Keywords: adhesive bonded joints, Hopkinson bars, out-of-plane tests, dynamic compression properties, damage mechanisms, heat dissipation

Procedia PDF Downloads 212
5142 The Omicron Variant BA.2.86.1 of SARS- 2 CoV-2 Demonstrates an Altered Interaction Network and Dynamic Features to Enhance the Interaction with the hACE2

Authors: Taimur Khan, Zakirullah, Muhammad Shahab

Abstract:

The SARS-CoV-2 variant BA.2.86 (Omicron) has emerged with unique mutations that may increase its transmission and infectivity. This study investigates how these mutations alter the Omicron receptor-binding domain's interaction network and dynamic properties (RBD) compared to the wild-type virus, focusing on its binding affinity to the human ACE2 (hACE2) receptor. Protein-protein docking and all-atom molecular dynamics simulations were used to analyze structural and dynamic differences. Despite the structural similarity to the wild-type virus, the Omicron variant exhibits a distinct interaction network involving new residues that enhance its binding capacity. The dynamic analysis reveals increased flexibility in the RBD, particularly in loop regions crucial for hACE2 interaction. Mutations significantly alter the secondary structure, leading to greater flexibility and conformational adaptability compared to the wild type. Binding free energy calculations confirm that the Omicron RBD has a higher binding affinity (-70.47 kcal/mol) to hACE2 than the wild-type RBD (-61.38 kcal/mol). These results suggest that the altered interaction network and enhanced dynamics of the Omicron variant contribute to its increased infectivity, providing insights for the development of targeted therapeutics and vaccines.

Keywords: SARS-CoV-2, molecular dynamic simulation, receptor binding domain, vaccine

Procedia PDF Downloads 21
5141 Development of a Software System for Management and Genetic Analysis of Biological Samples for Forensic Laboratories

Authors: Mariana Lima, Rodrigo Silva, Victor Stange, Teodiano Bastos

Abstract:

Due to the high reliability reached by DNA tests, since the 1980s this kind of test has allowed the identification of a growing number of criminal cases, including old cases that were unsolved, now having a chance to be solved with this technology. Currently, the use of genetic profiling databases is a typical method to increase the scope of genetic comparison. Forensic laboratories must process, analyze, and generate genetic profiles of a growing number of samples, which require time and great storage capacity. Therefore, it is essential to develop methodologies capable to organize and minimize the spent time for both biological sample processing and analysis of genetic profiles, using software tools. Thus, the present work aims the development of a software system solution for laboratories of forensics genetics, which allows sample, criminal case and local database management, minimizing the time spent in the workflow and helps to compare genetic profiles. For the development of this software system, all data related to the storage and processing of samples, workflows and requirements that incorporate the system have been considered. The system uses the following software languages: HTML, CSS, and JavaScript in Web technology, with NodeJS platform as server, which has great efficiency in the input and output of data. In addition, the data are stored in a relational database (MySQL), which is free, allowing a better acceptance for users. The software system here developed allows more agility to the workflow and analysis of samples, contributing to the rapid insertion of the genetic profiles in the national database and to increase resolution of crimes. The next step of this research is its validation, in order to operate in accordance with current Brazilian national legislation.

Keywords: database, forensic genetics, genetic analysis, sample management, software solution

Procedia PDF Downloads 370
5140 An Attempt to Decipher the Meaning of a Mithraic Motif

Authors: Attila Simon

Abstract:

The subject of this research is an element of Mithras' iconography. It is a new element in the series of research begun with the study of the Bull in the Boat motif. The stylized altars represented by the seven adjacent rectangles appear on only a small group of Mithraic reliefs, which may explain why they have received less attention and fewer attempts at decipherment than other motifs. Using Vermaseren's database, CIMRM (Corpus Inscriptionum et Monumentorum Religionis Mithriacae), one collected all the cases containing the motif under investigation, created a database of them grouped by location, then used a comparative method to compare the different forms of the motif and to isolate these cases, and finally evaluated the results. The aim of this research is to interpret the iconographic element in question and attempt to determine its place of origin. The study may provide an interpretation of a Mithraic representation that, to the best of the author's knowledge, has not been explained so far, and the question may generate scientific discourses.

Keywords: roman history, religion, Mithras, iconography

Procedia PDF Downloads 90
5139 Analysis of the Influence of Support Failure on the Dynamic Effect of Bridge Structure

Authors: Sun Fan, Wu Xiaoguang, Fang Miaomiao, Wei Chi

Abstract:

The degree of damage to the support is simulated by finite element software, and its influence on the static and dynamic effects of the bridge structure is analyzed. Four working conditions are selected for the study of bearing damage impact: the bearing is intact (condition 1), the bearing damage coefficient is 0.8 (condition 2), the bearing damage coefficient is 0.6 (condition 3), and the bearing damage coefficient is 0.4 (Working Condition 4). The effect value of the bridge structure under each working condition is calculated, and the simple-supported girder bridge and continuous girder bridge with typical spans are taken as examples to analyze the overall change of the bridge structure after the bearing completely fails.

Keywords: bridge bearing damage, dynamic response, finite element analysis, load conditions

Procedia PDF Downloads 230
5138 Dynamic Capabilities and Disorganization: A Conceptual Exploration

Authors: Dinuka Herath, Shelley Harrington

Abstract:

This paper prompts debate about whether disorganization can be positioned as a mechanism that facilitates the creation and enactment of important dynamic capabilities within an organization. This particular article is a conceptual exploration of the link between dynamic capabilities and disorganization and presents the case for agent-based modelling as a viable methodological tool which can be used to explore this link. Dynamic capabilities are those capabilities that an organization needs to sustain competitive advantage in complex environments. Disorganization is the process of breaking down restrictive organizational structures and routines that commonly reside in organizations in order to increase organizational performance. In the 20th century, disorganization was largely viewed as an undesirable phenomenon within an organization. However, the concept of disorganization has been revitalized and garnered research interest in the recent years due to studies which demonstrate some of the advantages of disorganization to an organization. Furthermore, recent Agent-based simulation studies have shown the capability of disorganization to be managed and argue for disorganization to be viewed as an enabler of organizational productivity. Given the natural state of disorganization and resulting fear this can create, this paper argues that instead of trying to ‘correct’ disorganization, it should be actively encouraged to have functional purpose. The study of dynamic capabilities emerged as a result of heightened dynamism and consequentially the very nature of dynamism denotes a level of fluidity and flexibility, something which this paper argues many organizations do not truly foster due to a constrained commitment to organization and order. We argue in this paper that the very state of disorganization is a state that should be encouraged to develop dynamic capabilities needed to not only deal with the complexities of the modern business environment but also to sustain competitive success. The significance of this paper stems from the fact that both dynamic capabilities and disorganization are two concepts that are gaining prominence in their respective academic genres. Despite the attention each concept has received individually, no conceptual link has been established to depict how they actually interact with each other. We argue that the link between these two concepts present a novel way of looking at organizational performance. By doing so, we explore the potential of these two concepts working in tandem in order to increase organizational productivity which has significant implications for both academics and practitioners alike.

Keywords: agent-based modelling, disorganization, dynamic capabilities, performance

Procedia PDF Downloads 317
5137 Dynamic Simulation for Surface Wear Prognosis of the Main Bearings in the Internal Combustion Engine

Authors: Yanyan Zhang, Ziyu Diao, Zhentao Liu, Ruidong Yan

Abstract:

The wear character of the main bearing is one of the critical indicators for the overhaul of an internal combustion engine, and the aim of this paper is to reveal the dynamic wear mechanism of the main bearings. A numerical simulation model combined multi-body dynamic equations of the engine, the average Reynolds equations of the bearing lubricant, asperity contact and wear model of the joint surfaces were established under typical operating conditions. The wear results were verified by experimental data, and then the influence of operating conditions, bearing clearance and cylinder pressure on the wear character of selected main bearings were analyzed. The results show that the contribution degree of different working conditions on the wear profile and depth of each bearing is obviously different, and the increase of joint clearance or cylinder pressure will accelerate the wear. The numerical model presented can be used to wear prognosis for joints and provide guidance for optimization design of sliding bearings.

Keywords: dynamic simulation, multi-body dynamics, sliding bearing, surface wear

Procedia PDF Downloads 148
5136 A New Complex Method for Integrated Warehouse Design in Aspect of Dynamic and Static Capacity

Authors: Tamas Hartvanyi, Zoltan Andras Nagy, Miklos Szabo

Abstract:

The dynamic and static capacity are two opposing aspect of warehouse design. Static capacity optimization aims to maximize the space-usage for goods storing, while dynamic capacity needs more free place to handling them. They are opposing by the building structure and the area utilization. According to Pareto principle: the 80% of the goods are the 20% of the variety. From the origin of this statement, it worth to store the big amount of same products by fulfill the space with minimal corridors, meanwhile the rest 20% of goods have the 80% variety of the whole range, so there is more important to be fast-reachable instead of the space utilizing, what makes the space fulfillment numbers worse. The warehouse design decisions made in present practice by intuitive and empiric impressions, the planning method is formed to one selected technology, making this way the structure of the warehouse homogeny. Of course the result can’t be optimal for the inhomogeneous demands. A new innovative model based on our research will be introduced in this paper to describe the technic capacities, what makes possible to define optimal cluster of technology. It is able to optimize the space fulfillment and the dynamic operation together with this cluster application.

Keywords: warehouse, warehouse capacity, warehouse design method, warehouse optimization

Procedia PDF Downloads 140