Search results for: fixed partial dentures
Commenced in January 2007
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Edition: International
Paper Count: 2544

Search results for: fixed partial dentures

2544 Improvement in Oral Health-Related Quality of Life of Adult Patients After Rehabilitation With Partial Dentures: A Systematic Review and Meta-Analysis

Authors: Adama NS Bah

Abstract:

Background: Loss of teeth has a negative influence on essential oral functions such as phonetics, mastication, and aesthetics. Dentists treat people with prosthodontic rehabilitation to recover essential oral functions. The oral health quality of life inventory reflects the success of prosthodontic rehabilitation. In many countries, the current conventional care delivered to replace missing teeth for adult patients involves the provision of removable partial dentures. Aim: The aim of this systematic review and meta-analysis is to gather the best available evidence to determine patients’ oral health-related quality of life improvement after treatment with partial dentures. Methods: We searched electronic databases from January 2010 to September 2019, including PubMed, ProQuest, Science Direct, Scopus and Google Scholar. In this paper, studies were included only if the average age was 30 years and above and also published in English. Two reviewers independently screened and selected all the references based on inclusion criteria using the PRISMA guideline, and assessed the quality of the included references using the Joanna Briggs Institute quality assessment tools. Data extracted were analyzed in RevMan 5.0 software, the heterogeneity between the studies was assessed using Forest plot, I2 statistics and chi-square test with a statistical P value less than 0.05 to indicate statistical significance. Random effect models were used in case of moderate or high heterogeneity. Four studies were included in the systematic review and three studies were pooled for meta-analysis. Results: Four studies included in the systematic review and three studies included in the meta-analysis with a total of 285 patients comparing the improvement in oral health-related quality of life before and after rehabilitation with partial denture, the pooled results showed a better improvement of oral health-related quality of life after treatment with partial dentures (mean difference 5.25; 95% CI [3.81, 6.68], p < 0.00001) favoring the wearing of partial dentures. In order to ascertain the reliability of the included studies for meta-analysis risk of bias was assessed and found to be low in all included studies for meta-analysis using the Cochrane collaboration tool for risk of bias assessment. Conclusion: There is high evidence that rehabilitation with partial dentures can improve the patient’s oral health-related quality of life measured with Oral Health Impact Profile 14. This review has clinical evidence value for dentists treating the expanding vulnerable adult population.

Keywords: meta-analysis, oral health impact profile, partial dentures, systematic review

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2543 Nadler's Fixed Point Theorem on Partial Metric Spaces and its Application to a Homotopy Result

Authors: Hemant Kumar Pathak

Abstract:

In 1994, Matthews (S.G. Matthews, Partial metric topology, in: Proc. 8th Summer Conference on General Topology and Applications, in: Ann. New York Acad. Sci., vol. 728, 1994, pp. 183-197) introduced the concept of a partial metric as a part of the study of denotational semantics of data flow networks. He gave a modified version of the Banach contraction principle, more suitable in this context. In fact, (complete) partial metric spaces constitute a suitable framework to model several distinguished examples of the theory of computation and also to model metric spaces via domain theory. In this paper, we introduce the concept of almost partial Hausdorff metric. We prove a fixed point theorem for multi-valued mappings on partial metric space using the concept of almost partial Hausdorff metric and prove an analogous to the well-known Nadler’s fixed point theorem. In the sequel, we derive a homotopy result as an application of our main result.

Keywords: fixed point, partial metric space, homotopy, physical sciences

Procedia PDF Downloads 399
2542 Adaptation and Habituation to new Complete Dentures

Authors: Mohamed Khaled Ahmed Azzam

Abstract:

Complete dentures, a non biological appliance, were and are still used to replace missing teeth and surrounding structures. Its main objectives are esthetics, speech, function and psychological state improvement. Dentists must realize that, just as dentate patients vary in their dental treatment complexity; edentulous patients also vary in the difficulty of their treatment plan. There are two main problems facing the removable Prosthodontist which harden his/her task how to please his patient with their new dentures being: Denture construction which however its fabrication is at the highest standards still is an unpleasant experience to all patients in the beginning and improves by time. This varies from one to several years according to the patient’s attitude, age, gender, socio-economical level and culture. The second problem of edentulous patients is both physical and psychological. Good interview, communication and note how patients present themselves for the concerns of their appearance, overall attitude and expectations concerning treatment is very important physically. On the psychological aspect patients have great difficulty to cope with new dentures to the extent of not using them at all. Hence their mind preparation should be commenced from day one by more than one method. This had a great impact on the acceptance which led to habituation to their dentures and patients were appreciative and pleased. In conclusion to successfully treat edentulous patients a great deal of information is required to complete a proper diagnosis, including patient mental attitude, past and present medical and dental conditions, and extra and intra-oral examinations. In addition to the clinical experience and skill of the whole dental team.

Keywords: complete dentures, edentulous patients, management of denture, psychological mind preparation

Procedia PDF Downloads 215
2541 Periodontal Soft Tissue Sculpturing and Use of Interim Appliance for Rehabilitation of Anterior Edentulousness: Case Report

Authors: Hande Yesil, Seda Aycan Altan, M. Vehbi Bal, Alper Uyar, O. Cumhur Sipahi

Abstract:

Purpose: Fixed partial dentures (FPDs) must fulfill functional requirements such as phonetics, chewing efficiency and esthetics especially in the anterior region. A convex type tissue surface is usually recommended for pontics of FPDs. That pontic design also provides suitable oral hygiene and ease of cleaning. However, high esthetic requirements and correct emergence profile are not always achievable because of the convex shape of adjacent soft tissues. Therefore, the ovate type pontic which fulfills the high esthetic demands of the patients may be a good alternative to the modified ridge lap pontic design. Clinical Report: A female patient referred with the complaint of anterior upper edentulousness. In the oral examination it was determined that teeth 11, 12, 21, 22 were deficient. A thick and convex gingival tissue that may cause aesthetic problems was also observed.. Periodontal augmentation surgery was performed to ensure proper papillary configuration and gingival contour. An interim removable partial denture (IRPD) which applied pressure to operated gingival tissues was fabricated postoperatively. The IRPD was used for 4 weeks and after completion of tissue sculpting, the permanent FPD with an ovate pontic was fabricated and cemented. After a follow-up period of 6 months, not any esthetical and hygienic problem was detected and the patient was satisfied with her prosthesis. Conclusion: It was concluded that shaping of gingival contours with IRPD and use of a FPD with ovate pontic fulfills all esthetic and hygienic requirements.

Keywords: interim appliance, ovate pontic, tissue sculpturing, fixed partial denture

Procedia PDF Downloads 245
2540 Comparison of Microbiological Assessment of Non-adhesive Use and the Use of Adhesive on Complete Dentures

Authors: Hyvee Gean Cabuso, Arvin Taruc, Danielle Villanueva, Channela Anais Hipolito, Jia Bianca Alfonso

Abstract:

Introduction: Denture adhesive aids to provide additional retention, support and comfort for patients with loose dentures, as well as for patients who seek to achieve optimal denture adhesion. But due to its growing popularity, arising oral health issues should be considered, including its possible impact that may alter the microbiological condition of the denture. Changes as such may further resolve to denture-related oral diseases that can affect the day-to-day lives of patients. Purpose: The study aims to assess and compare the microbiological status of dentures without adhesives versus dentures when adhesives were applied. The study also intends to identify the presence of specific microorganisms, their colony concentration and their possible effects on the oral microflora. This study also aims to educate subjects by introducing an alternative denture cleaning method as well as denture and oral health care. Methodology: Edentulous subjects age 50-80 years old, both physically and medically fit, were selected to participate. Before obtaining samples for the study, the alternative cleaning method was introduced by demonstrating a step-by-step cleaning process. Samples were obtained by swabbing the intaglio surface of their upper and lower prosthesis. These swabs were placed in a thioglycollate broth, which served as a transport and enrichment medium. The swabs were then processed through bacterial culture. The colony-forming units (CFUs) were calculated on MacConkey Agar Plate (MAP) and Blood Agar Plate (BAP) in order to identify and assess the microbiological status, including species identification and microbial counting. Result: Upon evaluation and analysis of collected data, the microbiological assessment of the upper dentures with adhesives showed little to no difference compared to dentures without adhesives, but for the lower dentures, (P=0.005), which is less than α = 0.05; therefore, the researchers reject (Ho) and that there is a significant difference between the mean ranks of the lower denture without adhesive to those with, implying that there is a significant decrease in the bacterial count. Conclusion: These results findings may implicate the possibility that the addition of denture adhesives may contribute to the significant decrease of microbial colonization on the dentures.

Keywords: denture, denture adhesive, denture-related, microbiological assessment

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2539 Dynamic Process Monitoring of an Ammonia Synthesis Fixed-Bed Reactor

Authors: Bothinah Altaf, Gary Montague, Elaine B. Martin

Abstract:

This study involves the modeling and monitoring of an ammonia synthesis fixed-bed reactor using partial least squares (PLS) and its variants. The process exhibits complex dynamic behavior due to the presence of heat recycling and feed quench. One limitation of static PLS model in this situation is that it does not take account of the process dynamics and hence dynamic PLS was used. Although it showed, superior performance to static PLS in terms of prediction, the monitoring scheme was inappropriate hence adaptive PLS was considered. A limitation of adaptive PLS is that non-conforming observations also contribute to the model, therefore, a new adaptive approach was developed, robust adaptive dynamic PLS. This approach updates a dynamic PLS model and is robust to non-representative data. The developed methodology showed a clear improvement over existing approaches in terms of the modeling of the reactor and the detection of faults.

Keywords: ammonia synthesis fixed-bed reactor, dynamic partial least squares modeling, recursive partial least squares, robust modeling

Procedia PDF Downloads 356
2538 Colonization of Candida Albicans on 3D Printed CAD/CAM Complete Denture Versus Conventional Complete Denture: Randomized Controlled Clinical Study

Authors: Eman Helal, Ahmed M. Esmat

Abstract:

Statement of problem: The development of computer-aided design/computer-aided manufacturing (CAD/CAM) resin dentures has simplified complete denture production. Most of the studies evaluated the mechanical properties of the material, but the hygienic performance of the CAD /CAM denture and their ability to maintain clean surfaces and minimize bacterial accumulation is still lacking. Purpose evaluation of the antibacterial characteristics of the 3D printed CAD/CAM denture and to compare it with the conventional heat polymerized acrylic denture base material. Methodology a total of thirty completely edentulous patients grouped randomly into two groups (Group I: Control group) received conventional heat polymerized acrylic resin complete dentures, (Group II: Test group) received 3D printed (CAD/CAM) dentures (stereolithographic PMMA), Samples of Candida albicans culture swabs were taken after 1 month and 3 months of dentures` insertion. A culture swab was obtained by scrubbing the fitting surface of the upper denture. At each time interval, three swab samples were collected from each patient and were inoculated in three individual culture media. Results: there was a significant difference in the colonization of Candida albicans to the fitting surface of the dentures between both groups (Group I: Conventional denture cases) exhibited more adhesion of Candida Albicans to the fitting surface than did (Group II: CAD/CAM cases) (P<0.05). Conclusion: 3D printed CAD/CAM complete denture showed minimal Candida adherence upon upper denture fitting compared to conventional heat-polymerized acrylic resin, which contributes to decreasing the incidence of denture stomatitis which is considered one of the most common problems among complete denture wearers.

Keywords: CAD/CAM denture, completely edentulous, elderly patients, 3D printing, antimicrobial efficiency, conventional denture, PMMA, Candida Albicans, denture stomatitis

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2537 The Functional Rehabilitation of Peri-Implant Tissue Defects: A Case Report

Authors: Özgür Öztürk, Cumhur Sipahi, Hande Yeşil

Abstract:

Implant retained restorations commonly consist of a metal-framework veneered with ceramic or composite facings. The increasing and expanding use of indirect resin composites in dentistry is a result of innovations in materials and processing techniques. Of special interest to the implant restorative field is the possibility that composites present significantly lower peak vertical and transverse forces transmitted at the peri-implant level compared to metal-ceramic supra structures in implant-supported restorations. A 43-year-old male patient referred to the department of prosthodontics for an implant retained fixed prosthesis. The clinical and radiographic examination of the patient demonstrated the presence of an implant in the right mandibular first molar tooth region. A considerable amount of marginal bone loss around the implant was detected in radiographic examinations combined with a remarkable peri-implant soft tissue deficiency. To minimize the chewing loads transmitted to the implant-bone interface it was decided to fabricate an indirect composite resin veneered single metal crown over a screw-retained abutment. At the end of the treatment, the functional and aesthetic deficiencies were fully compensated. After a 6 months clinical and radiographic follow-up period the not any additional pathologic invasion was detected in the implant-bone interface and implant retained restoration did not reveal any vehement complication.

Keywords: dental implant, fixed partial dentures, indirect composite resin, peri-implant defects

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2536 The Non-Uniqueness of Partial Differential Equations Options Price Valuation Formula for Heston Stochastic Volatility Model

Authors: H. D. Ibrahim, H. C. Chinwenyi, T. Danjuma

Abstract:

An option is defined as a financial contract that provides the holder the right but not the obligation to buy or sell a specified quantity of an underlying asset in the future at a fixed price (called a strike price) on or before the expiration date of the option. This paper examined two approaches for derivation of Partial Differential Equation (PDE) options price valuation formula for the Heston stochastic volatility model. We obtained various PDE option price valuation formulas using the riskless portfolio method and the application of Feynman-Kac theorem respectively. From the results obtained, we see that the two derived PDEs for Heston model are distinct and non-unique. This establishes the fact of incompleteness in the model for option price valuation.

Keywords: Black-Scholes partial differential equations, Ito process, option price valuation, partial differential equations

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2535 A 10 Year Review of the Complications of Ingested and Aspirated Dentures

Authors: Rory Brown, Jessica Daniels, Babatunde Oremule, William Tsang, Sadie Khwaja

Abstract:

Introduction: Dentures are common and are an intervention for both physical and psychological symptoms associated with tooth loss. However, the humble denture can cause morbidity and mortality if swallowed or aspirated. Numerous case reports document complications including hollow viscus perforation, fistula formation and airway compromise. The purpose of this review was to examine the literature documenting cases of swallowed or aspirated dentures over the past ten years to investigate factors that contribute to developing complications. Methods: A Medline literature search was performed to identify cases of denture ingestion or aspiration for over ten years. Data was collected to include patient, appliance and temporal factors that may contribute to developing complications including hollow viscus perforation, fistula formation, abscess, bowel obstruction, necrosis, hemorrhage and airway obstruction. The data was analyzed using observational and inferential statistics in the form of Chi-Squared and Pearson correlation tests. Results: Eighty-five cases of ingested or aspirated dentures were identified from 77 articles published between 1/10/2009 and 31/10/2019. Fourteen articles were excluded because they did not provide sufficient information on individual cases. Complications were documented in 37.6% of patients, and 2 cases resulted in death. There was no significant difference in complication risk based on patient age, hooked appliance, level of impaction, or radiolucency. However, symptoms of greater than 1-day duration are associated with an increased risk of complication (p=0.005). Increased time from ingestion or aspiration to removal is associated with an increased risk of complications, and the p-value remains significant up to and including day 4 (p=0.017). Conclusions: With denture use predicted to rise complications from the denture, ingestion and aspiration may become more frequent. We have demonstrated that increased symptom duration significantly increases the risk of developing complications. Additionally, we established the risk of developing complications is significantly reduced if the denture is removed with four days of aspiration or ingestion. By actively intervening early when presented with a case of swallowed or aspirated dentures, we may be able to reduce the morbidity associated with this unassuming device.

Keywords: aspiration, denture, ingestion, endoscopic foreign, body removal, foreign body impaction

Procedia PDF Downloads 94
2534 Maryland Restoration of Anterior Tooth Loss as a Minimal Invasive Dentistry: An Alternative Treatment

Authors: B. Oral, C. Bal, M. S. Kar, A. Akgürbüz

Abstract:

Loss of maxillary central incisors occurs in many patients, and the treatment of young adults with this problem is a challenge for both prosthodontists and orthodontists. Common treatment alternatives are distalization of adjacent teeth and fabrication of a conventional 3-unit fixed partial denture, a single implant supported crown restoration or a resin-bonded fixed partial denture. This case report describes the indication of a resin-bonded fixed partial denture, preparation of the abutment teeth and the prosthetic procedures. The technique described here represents a conservative, esthetically pleasing and rapid solution for the missing maxillary central incisor when implant placement and/or guided bone regeneration techniques are not feasible because of financial, social or time restrictions. In this case a 16 year-old female patient who lost her maxillary left central incisor six years ago in a bicycle accident applied to our clinic with a major complaint of her unaesthetic appearance associated with the loss of her maxillary left central incisor. Although there was an indication for orthodontic treatment because of the limited space at the traumatized area, the patient did not accept to receive any orthodontic procedure. That is why an implant supported restoration could not be an option for the narrow area. Therefore maryland bridge as a minimal invasive dental therapy was preferred as a retention appliance so the patient's aesthetic appearance was restored.

Keywords: Maryland bridge, single tooth restoration, aesthetics, maxillary central incisors

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2533 On the Relation between λ-Symmetries and μ-Symmetries of Partial Differential Equations

Authors: Teoman Ozer, Ozlem Orhan

Abstract:

This study deals with symmetry group properties and conservation laws of partial differential equations. We give a geometrical interpretation of notion of μ-prolongations of vector fields and of the related concept of μ-symmetry for partial differential equations. We show that these are in providing symmetry reduction of partial differential equations and systems and invariant solutions.

Keywords: λ-symmetry, μ-symmetry, classification, invariant solution

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2532 Investigation on Behavior of Fixed-Ended Reinforced Concrete Deep Beams

Authors: Y. Heyrani Birak, R. Hizaji, J. Shahkarami

Abstract:

Reinforced Concrete (RC) deep beams are special structural elements because of their geometry and behavior under loads. For example, assumption of strain- stress distribution is not linear in the cross section. These types of beams may have simple supports or fixed supports. A lot of research works have been conducted on simply supported deep beams, but little study has been done in the fixed-end RC deep beams behavior. Recently, using of fixed-ended deep beams has been widely increased in structures. In this study, the behavior of fixed-ended deep beams is investigated, and the important parameters in capacity of this type of beams are mentioned.

Keywords: deep beam, capacity, reinforced concrete, fixed-ended

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2531 Colour Recognition Pen Technology in Dental Technique and Dental Laboratories

Authors: M. Dabirinezhad, M. Bayat Pour, A. Dabirinejad

Abstract:

Recognition of the color spectrum of the teeth plays a significant role in the dental laboratories to produce dentures. Since there are various types and colours of teeth for each patient, there is a need to specify the exact and the most suitable colour to produce a denture. Usually, dentists utilize pallets to identify the color that suits a patient based on the color of the adjacent teeth. Consistent with this, there can be human errors by dentists to recognize the optimum colour for the patient, and it can be annoying for the patient. According to the statistics, there are some claims from the patients that they are not satisfied by the colour of their dentures after the installation of the denture in their mouths. This problem emanates from the lack of sufficient accuracy during the colour recognition process of denture production. The colour recognition pen (CRP) is a technology to distinguish the colour spectrum of the intended teeth with the highest accuracy. CRP is equipped with a sensor that is capable to read and analyse a wide range of spectrums. It is also connected to a database that contains all the spectrum ranges, which exist in the market. The database is editable and updatable based on market requirements. Another advantage of this invention can be mentioned as saving time for the patients since there is no need to redo the denture production in case of failure on the first try.

Keywords: colour recognition pen, colour spectrum, dental laboratory, denture

Procedia PDF Downloads 159
2530 Characteristics of Different Solar PV Modules under Partial Shading

Authors: Hla Hla Khaing, Yit Jian Liang, Nant Nyein Moe Htay, Jiang Fan

Abstract:

Partial shadowing is one of the problems that are always faced in terrestrial applications of solar photovoltaic (PV). The effects of partial shadow on the energy yield of conventional mono-crystalline and multi-crystalline PV modules have been researched for a long time. With deployment of new thin-film solar PV modules in the market, it is important to understand the performance of new PV modules operating under the partial shadow in the tropical zone. This paper addresses the impacts of different partial shadowing on the operating characteristics of four different types of solar PV modules that include multi-crystalline, amorphous thin-film, CdTe thin-film and CIGS thin-film PV modules.

Keywords: partial shade, CdTe, CIGS, multi-crystalline (mc-Si), amorphous silicon (a-Si), bypass diode

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2529 A New Fixed Point Theorem for Almost θ-Contraction

Authors: Hichem Ramoul

Abstract:

In this work, we introduce a new type of contractive maps and we establish a new fixed point theorem for the class of almost θ-contractions (more general than the class of almost contractions) in a complete generalized metric space. The major novelty of our work is to prove a new fixed point result by weakening some hypotheses imposed on the function θ which will change completely the classical technique used in the literature review to prove fixed point theorems for almost θ-contractions in a complete generalized metric space.

Keywords: almost contraction, almost θ-contraction, fixed point, generalized metric space

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2528 [Keynote Talk]: Existence of Random Fixed Point Theorem for Contractive Mappings

Authors: D. S. Palimkar

Abstract:

Random fixed point theory has received much attention in recent years, and it is needed for the study of various classes of random equations. The study of random fixed point theorems was initiated by the Prague school of probabilistic in the 1950s. The existence and uniqueness of fixed points for the self-maps of a metric space by altering distances between the points with the use of a control function is an interesting aspect in the classical fixed point theory. In a new category of fixed point problems for a single self-map with the help of a control function that alters the distance between two points in a metric space which they called an altering distance function. In this paper, we prove the results of existence of random common fixed point and its uniqueness for a pair of random mappings under weakly contractive condition for generalizing alter distance function in polish spaces using Random Common Fixed Point Theorem for Generalized Weakly Contractions.

Keywords: Polish space, random common fixed point theorem, weakly contractive mapping, altering function

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2527 Image Transform Based on Integral Equation-Wavelet Approach

Authors: Yuan Yan Tang, Lina Yang, Hong Li

Abstract:

Harmonic model is a very important approximation for the image transform. The harmanic model converts an image into arbitrary shape; however, this mode cannot be described by any fixed functions in mathematics. In fact, it is represented by partial differential equation (PDE) with boundary conditions. Therefore, to develop an efficient method to solve such a PDE is extremely significant in the image transform. In this paper, a novel Integral Equation-Wavelet based method is presented, which consists of three steps: (1) The partial differential equation is converted into boundary integral equation and representation by an indirect method. (2) The boundary integral equation and representation are changed to plane integral equation and representation by boundary measure formula. (3) The plane integral equation and representation are then solved by a method we call wavelet collocation. Our approach has two main advantages, the shape of an image is arbitrary and the program code is independent of the boundary. The performance of our method is evaluated by numerical experiments.

Keywords: harmonic model, partial differential equation (PDE), integral equation, integral representation, boundary measure formula, wavelet collocation

Procedia PDF Downloads 511
2526 Design of Reconfigurable Fixed-Point LMS Adaptive FIR Filter

Authors: S. Padmapriya, V. Lakshmi Prabha

Abstract:

In this paper, an efficient reconfigurable fixed-point Least Mean Square Adaptive FIR filter is proposed. The proposed architecture has two methods of operation: one is area efficient design and the other is optimized power. Pipelining of the adder blocks and partial product generator are used to achieve low area and reversible logic is used to obtain low power design. Depending upon the input samples and filter coefficients, one of the techniques is chosen. Least-Mean-Square adaptation is performed to update the weights. The architecture is coded using Verilog and synthesized in cadence encounter 0.18μm technology. The synthesized results show that the area reduction ratio of the proposed when compared with conventional technique is about 1.2%.

Keywords: adaptive filter, carry select adder, least mean square algorithm, reversible logic

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2525 Assessment of Solid Insulating Material Using Partial Discharge Characteristics

Authors: Qasim Khan, Furkan Ahmad, Asfar A. Khan, M. Saad Alam, Faiz Ahmad

Abstract:

In this paper, partial discharge analysis is performed in cavities artificially created in insulation. The setup is according with Cigre-II Method. Circular Samples created from Perspex Sheet with different configuration with changing number of cavities. Assessment of insulation health can be performed by Partial Discharge measurement as this has been found to be important means of condition monitoring. The experiments are done using MPD 540, which is a modern partial discharge measurement system. By analyzing the PD activity obtained for various voids/cavities, it is observed that the PD voltages show variation for cavity’s diameter, depth even for its ratios. This can be employed for scrutiny of insulation system.

Keywords: partial discharges, condition monitoring, insulation defects, degradation and corrosion, PMMA

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2524 Tax Competition and Partial Tax Coordination under Fiscal Decentralization

Authors: Patricia Sanz-Cordoba, Bernd Theilen

Abstract:

This article analyzes the conditions where decentralization and partial tax harmonization in a coalition of asymmetric jurisdictions plays a role in the fight of fiscal competition (i.e. the race to bottom). Starting from a centralized economies, we use the ZM-W model to analyze the fiscal competition and coordination among three countries. We find that the asymmetry of jurisdictions facilitates partial tax harmonization between jurisdictions when these asymmetries are not too large. Furthermore, when the asymmetries are large enough, the level of labor tax plays an important role in the decision of decentralize capital tax. Accordingly, decentralization is achievable when labor tax is low. This result indicates that decentralization and partial tax harmonization between jurisdictions can be possible results in order to fight the negative externalities from fiscal competition, and more in the European Union countries where the asymmetries are substantial.

Keywords: centralization, decentralization, fiscal competition, partial tax harmonization

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2523 Comparison of Stereotactic Body Radiation Therapy Virtual Treatment Plans Obtained With Different Collimators in the Cyberknife System in Partial Breast Irradiation: A Retrospective Study

Authors: Öznur Saribaş, Si̇bel Kahraman Çeti̇ntaş

Abstract:

It is aimed to compare target volume and critical organ doses by using CyberKnife (CK) in accelerated partial breast irradiation (APBI) in patients with early stage breast cancer. Three different virtual plans were made for Iris, fixed and multi-leaf collimator (MLC) for 5 patients who received radiotherapy in the CyberKnife system. CyberKnife virtual plans were created, with 6 Gy per day totaling 30 Gy. Dosimetric parameters for the three collimators were analyzed according to the restrictions in the NSABP-39/RTOG 0413 protocol. The plans ensured critical organs were protected and GTV received 95 % of the prescribed dose. The prescribed dose was defined by the isodose curve of a minimum of 80. Homogeneity index (HI), conformity index (CI), treatment time (min), monitor unit (MU) and doses taken by critical organs were compared. As a result of the comparison of the plans, a significant difference was found for the duration of treatment, MU. However, no significant difference was found for HI, CI. V30 and V15 values of the ipsi-lateral breast were found in the lowest MLC. There was no significant difference between Dmax values for lung and heart. However, the mean MU and duration of treatment were found in the lowest MLC. As a result, the target volume received the desired dose in each collimator. The contralateral breast and contralateral lung doses were the lowest in the Iris. Fixed collimator was found to be more suitable for cardiac doses. But these values did not make a significant difference. The use of fixed collimators may cause difficulties in clinical applications due to the long treatment time. The choice of collimator in breast SBRT applications with CyberKnife may vary depending on tumor size, proximity to critical organs and tumor localization.

Keywords: APBI, CyberKnife, early stage breast cancer, radiotherapy.

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2522 Measurements of Radial Velocity in Fixed Fluidized Bed for Fischer-Tropsch Synthesis Using LDV

Authors: Xiaolai Zhang, Haitao Zhang, Qiwen Sun, Weixin Qian, Weiyong Ying

Abstract:

High temperature Fischer-Tropsch synthesis process use fixed fluidized bed as a reactor. In order to understand the flow behavior in the fluidized bed better, the research of how the radial velocity affect the entire flow field is necessary. Laser Doppler Velocimetry (LDV) was used to study the radial velocity distribution along the diameter direction of the cross-section of the particle in a fixed fluidized bed. The velocity in the cross-section is fluctuating within a small range. The direction of the speed is a random phenomenon. In addition to r/R is 1, the axial velocity are more than 6 times of the radial velocity, the radial velocity has little impact on the axial velocity in a fixed fluidized bed.

Keywords: Fischer-Tropsch synthesis, Fixed fluidized bed, LDV, Velocity

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2521 Algorithms Utilizing Wavelet to Solve Various Partial Differential Equations

Authors: K. P. Mredula, D. C. Vakaskar

Abstract:

The article traces developments and evolution of various algorithms developed for solving partial differential equations using the significant combination of wavelet with few already explored solution procedures. The approach depicts a study over a decade of traces and remarks on the modifications in implementing multi-resolution of wavelet, finite difference approach, finite element method and finite volume in dealing with a variety of partial differential equations in the areas like plasma physics, astrophysics, shallow water models, modified Burger equations used in optical fibers, biology, fluid dynamics, chemical kinetics etc.

Keywords: multi-resolution, Haar Wavelet, partial differential equation, numerical methods

Procedia PDF Downloads 258
2520 A Minimally Invasive Approach Using Bio-Miniatures Implant System for Full Arch Rehabilitation

Authors: Omid Allan

Abstract:

The advent of ultra-narrow diameter implants initially offered an alternative to wider conventional implants. However, their design limitations have restricted their applicability primarily to overdentures and cement-retained fixed prostheses, often with unpredictable long-term outcomes. The introduction of the new Miniature Implants has revolutionized the field of implant dentistry, leading to a more streamlined approach. The utilization of Miniature Implants has emerged as a promising alternative to the traditional approach that entails the traumatic sequential bone drilling procedures and the use of conventional implants for full and partial arch restorations. The innovative "BioMiniatures Implant System serves as a groundbreaking bridge connecting mini implants with standard implant systems. This system allows practitioners to harness the advantages of ultra-small implants, enabling minimally invasive insertion and facilitating the application of fixed screw-retained prostheses, which were only available to conventional wider implant systems. This approach streamlines full and partial arch rehabilitation with minimal or even no bone drilling, significantly reducing surgical risks and complications for clinicians while minimizing patient morbidity. The ultra-narrow diameter and self-advancing features of these implants eliminate the need for invasive and technically complex procedures such as bone augmentation and guided bone regeneration (GBR), particularly in cases involving thin alveolar ridges. Furthermore, the absence of a microcap between the implant and abutment eliminates the potential for micro-leakage and micro-pumping effects, effectively mitigating the risk of marginal bone loss and future peri-implantitis. The cumulative experience of restoring over 50 full and partial arch edentulous cases with this system has yielded an outstanding success rate exceeding 97%. The long-term success with a stable marginal bone level in the study firmly establishes these implants as a dependable alternative to conventional implants, especially for full arch rehabilitation cases. Full arch rehabilitation with these implants holds the promise of providing a simplified solution for edentulous patients who typically present with atrophic narrow alveolar ridges, eliminating the need for extensive GBR and bone augmentation to restore their dentition with fixed prostheses.

Keywords: mini-implant, biominiatures, miniature implants, minimally invasive dentistry, full arch rehabilitation

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2519 Formation of ZnS/ZnO Heterojunction for Photocatalytic Hydrogen Evolution Using Partial Oxidation and Chemical Precipitation Synthesis Methods

Authors: Saba Didarataee, Abbas Ali Khodadadi, Yadollah Mortazavi, Fatemeh Mousavi

Abstract:

Photocatalytic water splitting is one of the most attractive alternative methods for hydrogen evolution. A variety of nanoparticle engineering techniques were introduced to improve the activity of semiconductor photocatalysts. Among these methods, heterojunction formation is an appealing method due to its ability to effectively preventing electron-hole recombination and improving photocatalytic activity. Reaching an optimal ratio of the two target semiconductors for the formation of heterojunctions is still an open question. Considering environmental issues as well as the cost and availability, ZnS and ZnO are frequently studied as potential choices. In this study, first, the ZnS nanoparticle was synthesized in a hydrothermal process; the formation of ZnS nanorods with a diameter of 14-30 nm was confirmed by field emission scanning electron microscope (FESEM). Then two different methods, partial oxidation and chemical precipitation were employed to construct ZnS/ZnO core-shell heterojunction. X-ray diffraction (XRD), BET, and diffuse reflectance spectroscopy (DRS) analysis were carried out to determine crystallite phase, surface area, and bandgap of photocatalysts. Furthermore, the temperature of oxidation was specified by a temperature programmed oxidation (TPO) and was fixed at 510℃, at which mild oxidation occurred. The bandgap was calculated by the Kubelka-Munk method and decreased by increasing oxide content from 3.53 (pure ZnS) to 3.18 (pure ZnO). The optimal samples were determined by testing the photocatalytic activity of hydrogen evolution in a quartz photoreactor with side irradiation of UVC lamps with a wavelength of 254 nm. In both procedures, it was observed that the photocatalytic activity of the ZnS/ZnO composite was sensibly higher than the pure ZnS and ZnO, which is attributed to forming a type-II heterostructure. The best ratio of oxide to sulfide was 0.24 and 0.37 in partial oxidation and chemical precipitation, respectively. The highest hydrogen evolution was 1081 µmol/gr.h, gained from partial oxidizing of ZnS nanoparticles at 510℃ for 30 minutes.

Keywords: heterostructure, hydrogen, partial oxidation, photocatalyst, water splitting, ZnS

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2518 Performance Analysis of LINUX Operating System Connected in LAN Using Gumbel-Hougaard Family Copula Distribution

Authors: V. V. Singh

Abstract:

In this paper we have focused on the study of a Linux operating system connected in a LAN (local area network). We have considered two different topologies STAR topology (subsystem-1) and BUS topology (subsystem-2) which are placed at two different places and connected to a server through a hub. In both topologies BUS topology and STAR topology, we have assumed 'n' clients. The system has two types of failure partial failure and complete failure. Further the partial failure has been categorized as minor partial failure and major partial failure. It is assumed that minor partial failure degrades the subsystem and the major partial failure brings the subsystem to break down mode. The system can completely failed due to failure of server hacking and blocking etc. The system is studied by supplementary variable technique and Laplace transform by taking different types of failure and two types of repairs. The various measures of reliability like availability of system, MTTF, profit function for different parametric values has been discussed.

Keywords: star topology, bus topology, hacking, blocking, linux operating system, Gumbel-Hougaard family copula, supplementary variable

Procedia PDF Downloads 535
2517 Ultra-Low NOx Combustion Technology of Liquid Fuel Burner

Authors: Sewon Kim, Changyeop Lee

Abstract:

A new concept of in-furnace partial oxidation combustion is successfully applied in this research. The burner is designed such that liquid fuel is prevaporized in the furnace then injected into a fuel rich combustion zone so that a partial oxidation reaction occurs. The effects of equivalence ratio, thermal load, injection distance and fuel distribution ratio on the NOx and CO are experimentally investigated. This newly developed burner showed very low NOx emission level, about 15 ppm when light oil is used as a fuel.

Keywords: burner, low NOx, liquid fuel, partial oxidation

Procedia PDF Downloads 292
2516 Free Convection from a Perforated Spinning Cone with Heat Generation, Temperature-Dependent Viscosity and Partial Slip

Authors: Gilbert Makanda

Abstract:

The problem of free convection from a perforated spinning cone with viscous dissipation, temperature-dependent viscosity, and partial slip was studied. The boundary layer velocity and temperature profiles were numerically computed for different values of the spin, viscosity variation, inertia drag force, Eckert, suction/blowing parameters. The partial differential equations were transformed into a system of ordinary differential equations which were solved using the fourth-order Runge-Kutta method. This paper considered the effect of partial slip and spin parameters on the swirling velocity profiles which are rarely reported in the literature. The results obtained by this method was compared to those in the literature and found to be in agreement. Increasing the viscosity variation parameter, spin, partial slip, Eckert number, Darcian drag force parameters reduce swirling velocity profiles.

Keywords: free convection, suction/injection, partial slip, viscous dissipation

Procedia PDF Downloads 214
2515 Control of Underactuated Biped Robots Using Event Based Fuzzy Partial Feedback Linearization

Authors: Omid Heydarnia, Akbar Allahverdizadeh, Behnam Dadashzadeh, M. R. Sayyed Noorani

Abstract:

Underactuated biped robots control is one of the interesting topics in robotics. The main difficulties are its highly nonlinear dynamics, open-loop instability, and discrete event at the end of the gait. One of the methods to control underactuated systems is the partial feedback linearization, but it is not robust against uncertainties and disturbances that restrict its performance to control biped walking and running. In this paper, fuzzy partial feedback linearization is presented to overcome its drawback. Numerical simulations verify the effectiveness of the proposed method to generate stable and robust biped walking and running gaits.

Keywords: underactuated system, biped robot, fuzzy control, partial feedback linearization

Procedia PDF Downloads 309