Mems Tabanlı Kuvvet Algılayıcıları İle Mikro Newton Mertebesinde Ölçüm

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2013Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2013Nanoteknolojideki gelişmeler sayesinde mikro ve nano seviyesindeki küçük ölçeklerde kuvvet üretimi ve üretilen kuvvetin ölçülmesi hem endüstrinin hem de akademinin ilgi alanına girmektedir. Bu çalışmada önerilen kuvvet ölçümü sistemi, yekpare olarak üretilmiş bir yay sistemi ve üçlü algılayıcı elektrot geometrisinden meydana gelmektedir. Bu elektrot kümelerinden ikisi sabit, birisi hareketli durumdadır. Dış bir kuvvetten uygulanan tahrik sonucunda oluşan yer değiştirme, hareketli elektrot kümesinin sabit kümelere göre yer değiştirmesine sebep olur. Bunun sonucunda sistemde oluşan sığa değişimi, sabit elektrot kümelerine uygulanan ve 1800 faz farkına sahip olan AC gerilimi neticesinde hareketli plakadan DC gerilimi olarak okunur. Bu çalışmada en fazla 30 N kuvveti okuyabilen bir kuvvet algılayıcı tasarımı gerçekleştirildi. Tasarım kriterlerini kontrol etmek amacıyla sonlu elemanlar yazılımı ile yöntem doğrulaması sağlandı. Bir sonraki adım olarak, tasarımı yapılan kuvvet algılayıcı, mikro-üretim yöntemleri kullanılarak imal edilecektir.With the continuous advances in the field of nanotechnology, both force generation and force measurement techniques at micro and nano scales are widely employed in industry and academia. The proposed force measurement system of this work consists of a monolithic flexural part and a sensor with the three-electrode geometry, namely “tri-plate geometry”, for capacitive displacement sensing. One of these sets of electrodes is movable, whereas the remaining two are fixed. Displacement of the movable set of electrodes induced by an external source results in a capacitive difference in between movable and fixed set of electrodes. This displacement is then sensed on the movable stack as a DC voltage output by applying an AC voltage of 1800 phase difference to the two fixed electrode sets. In this study, we propose a design of a force sensor which is able to detect a maximum force of 30 N. To verify the design, finite element simulations are carried out and shown to be in agreement with the design criteria. As a final step, fabrication of the force sensor will be carried out

Production of a Piece of Custom-Made Abutment Screwdriver: Technique and Case Report.

Crown fractures, framework fractures, and abutment screw loosening or screw fracture are examples of mechanical implant failures. Abutment screw loosening is a serious problem that can result in abutment screw fractures. This clinical report describes the production method of a custom-made abutment screwdriver piece for a patient with abutment screw loosening

Efficacy of polishing kits on the surface roughness and color stability of different composite resins

Objective: Different polishing kits may have different effects on the composite resin surfaces. The aim of this study was to evaluate the surface roughness and color stability of four different composites which was applied different polishing technique. Materials and Methods: Thirty specimens were made for each composite resin group (nanohybrid, GrandioSo-GS; nanohybrid, Clearfil Majesty Esthetic-CME; hybrid, Valux Plus-VP; micro-hybrid, Ruby Comp-RC; [15 mm in diameter and 2 mm height]), with the different monomer composition and particle size from a total of 120 specimens. Each composite group was divided into three subgroups (n = 10). The first subgroup of the each composite subgroups served as control (C) and had no surface treatment. The second subgroup of the each composite resin groups was polished with finishing discs (Bisco Finishing Discs; Bisco Inc., Schaumburg, IL, USA). The third subgroup of the each composite resin was polished with polishing wheel (Enhance and PoGo, Dentsply, Konstanz, Germany). The surface roughness and the color differences measurement of the specimens were made and recorded. The data were compared using Kruskal-Wallis test, and regression analysis was used in order to examine the correlation between surface roughness and color differences of the specimens (= 0.05). Results: The Kruskal-Wallis test indicated significant difference among the composite resins in terms of ΔE (P < 0.05), and there was no statistically significant difference among composite resins in terms of surface roughness (P > 0.05). Result of the regression analysis indicated statistically significant correlation between Ra and ΔE values (P < 0.05, r2= 0.74). Conclusion: The findings of the present study have clinical relevance in the choice of polishing kits used. © 2017 Nigerian Journal of Clinical Practice

Efficacy of polishing kits on the surface roughness and color stability of different composite resins.

OBJECTIVE: Different polishing kits may have different effects on the composite resin surfaces. The aim of this study was to evaluate the surface roughness and color stability of four different composites which was applied different polishing technique. MATERIALS AND METHODS: Thirty specimens were made for each composite resin group (nanohybrid, GrandioSo-GS; nanohybrid, Clearfil Majesty Esthetic-CME; hybrid, Valux Plus-VP; micro-hybrid, Ruby Comp-RC; [15 mm in diameter and 2 mm height]), with the different monomer composition and particle size from a total of 120 specimens. Each composite group was divided into three subgroups (n = 10). The first subgroup of the each composite subgroups served as control (C) and had no surface treatment. The second subgroup of the each composite resin groups was polished with finishing discs (Bisco Finishing Discs; Bisco Inc., Schaumburg, IL, USA). The third subgroup of the each composite resin was polished with polishing wheel (Enhance and PoGo, Dentsply, Konstanz, Germany). The surface roughness and the color differences measurement of the specimens were made and recorded. The data were compared using Kruskal-Wallis test, and regression analysis was used in order to examine the correlation between surface roughness and color differences of the specimens (α = 0.05). RESULTS: The Kruskal-Wallis test indicated significant difference among the composite resins in terms of ΔE (P 0.05). Result of the regression analysis indicated statistically significant correlation between Ra and ΔE values (P < 0.05, r2 = 0.74). CONCLUSION: The findings of the present study have clinical relevance in the choice of polishing kits used

Effect of alpha-lipoic acid on small fibre neuropathy findings in patients with type 2 diabetes mellitus

Objective: Cutaneous silent period (CSP) is an inhibitory spinal reflex and the afferent arm of this response involves A-delta nerve fibers. The aim of this study was to investigate CSP parameters in patients with type 2 diabetes mellitus (T2DM) and to examine the effects of alpha-lipoic acid (ALA) treatment on CSP. To the best of our knowledge, this investigation has not yet been carried out until date. Methods: Seventeen patients with T2DM and 23 healthy volunteers were studied. CSP latency and duration in the upper and lower extremities of both the groups were examined. In T2DM patients, the variables were examined before and after ALA treatment. Results: CSP latency in T2DM patients was longer than that in the controls. In the patient group, CSP latency in the upper and lower extremities and CSP Latency Differences (LD) shortened in the third month after treatment compared with the pre-treatment values. Conclusions: The results suggest that ALA treatment may alleviate small-fiber neuropathy in T2DM patients and that CSP may be a useful supportive tool to evaluate ALA treatment effectiveness. © 2015, Ege University Press. All rights reserved