scholarly journals CONTROL OF THE CASIMIR FORCE USING SEMICONDUCTOR TEST BODIES

2011 ◽  
Vol 25 (02) ◽  
pp. 171-230 ◽  
Author(s):  
G. L. KLIMCHITSKAYA ◽  
U. MOHIDEEN ◽  
V. M. MOSTEPANENKO
Keyword(s):  
Casimir Force ◽  
Laser Light ◽  
Theoretical Work ◽  
Charge Carriers ◽  
Optical Modulation ◽  
Semiconductor Test ◽  
Advantages And Disadvantages ◽  
Force Magnitude ◽  
Proximity Force Approximation ◽  
The Difference

We describe experimental and related theoretical work on the measurement of the Casimir force using semiconductor test bodies. This field of research started in 2005 and several important and interesting results have already been obtained. Specifically, the Casimir force or its gradient was measured in the configuration of an Au -coated sphere and different semiconductor surfaces. It was found that the force magnitude depends significantly on the replacement of the metal with a semiconductor and on the concentration of charge carriers in the semiconductor material. Special attention is paid to the experiment on the optical modulation of the Casimir force. In this experiment the difference in Casimir force between an Au -coated sphere and a Si plate in the presence and in the absence of laser light was measured. Possible applications of this experiment are discussed, specifically, for the realization of the pulsating Casimir force in three-layer systems. Theoretical problems arising from the comparison of the experimental data for the difference in Casimir force with the Lifshitz theory are analyzed. We consider the possibility to control the magnitude of the Casimir force in phase transitions of semiconductor materials. Experiments on measuring the Casimir force gradient between an Au -coated sphere and a Si plate covered with rectangular corrugations of different characters are also described. Here, we discuss the interplay between the material properties and nontrivial geometry and the applicability of the proximity force approximation. The review contains comparison between different experiments and analysis of their advantages and disadvantages.

Microencapsulation and Nanoencapsulation: A Review

2017 ◽  
Vol 9 (3) ◽  
Author(s):  
V. Suganya ◽  
V. Anuradha
Keyword(s):  
Drug Release ◽  
New Technology ◽  
Inert Material ◽  
Food Industries ◽  
Control Drug ◽  
Advantages And Disadvantages ◽  
Nano Scale ◽  
Pharmaceutical Industries ◽  
The Difference ◽  
Control Drug Release

Encapsulation is a process of enclosing the substances within an inert material which protects from environment as well as control drug release. Recently, two type of encapsulation has been performed in several research. Nanoencapsulation is the coating of various substances within another material at sizes on the nano scale. Microencapsulation is similar to nanoencapsulation aside from it involving larger particles and having been done for a greater period of time than nanoencapsulation. Encapsulation is a new technology that has wide applications in pharmaceutical industries, agrochemical, food industries and cosmetics. In this review, the difference between micro and nano encapsulation has been explained. This article gives an overview of different methods and reason for encapsulation. The advantages and disadvantages of micro and nano encapsulation technology were also clearly mentioned in this paper.

scholarly journals Monopolar Diathermy Tonsillectomy Versus Dissection Method Tonsillectomy

KYAMC Journal ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 21-24
Author(s):  
Md Abdus Salam ◽  
Md Mahbub Alam ◽  
Rezwan Ahmed ◽  
Md Sultan Mahmud
Keyword(s):  
Postoperative Pain ◽  
Postoperative Bleeding ◽  
Throat Pain ◽  
Medical College ◽  
Advantages And Disadvantages ◽  
Case Surgery ◽  
Group A ◽  
The Difference ◽  
Group B ◽  
Dissection Method

Background: Tonsillectomy is one of the most common surgical procedures performed worldwide by otorhinolaryngologists for different indications. Tonsillectomy is often performed as day-case surgery, which increases the demands of a satisfactory postoperative pain control and a low risk of early postoperative bleeding. Objective: The aim of the study was to compare the Monopolar diathermy and Dissection methods of tonsillectomy and evaluate their advantages and disadvantages during surgery, convalescence. Materials and Methods: Two hundred children were recruited for this study during the period of five years from January, 2014 to December, 2018 at Otolaryngology department of Khwaja Yunus Ali Medical College and Hospital (KYAMCH). Subjects between the age of 5 and 25 years listed for tonsillectomy were included. Subjects were recommended not to have aspirin within the 2 weeks before surgery. Results: The mean duration of operation was found 10.6±0.4 minutes in group A and 17.0±0.7 minutes in group B. The difference was statistically significant (p<0.05) between two groups. At 1st day, 11(11.0%) patients had throat pain in group A and 23(23.0%) in group B. At 2nd day, 14(14.0%) patients had throat pain in group A and 25(25.0%) in group B. Which were statistically significant (p<0.05) between two groups. Conclusion: The monopolar diathermy tonsillectomy appears to cause less bleeding, postoperative pain and less time consuming in compare with the dissection tonsillectomy although patients experience slightly more pain than dissection Method. KYAMC Journal Vol. 10, No.-1, April 2019, Page 21-24

MODIFICATION OF CASIMIR FORCES DUE TO BAND GAPS IN PERIODIC STRUCTURES

2002 ◽  
Vol 17 (06n07) ◽  
pp. 798-803 ◽  
Author(s):  
C. VILLARREAL ◽  
R. ESQUIVEL-SIRVENT ◽  
G. H. COCOLETZI
Keyword(s):  
Density Of States ◽  
Casimir Force ◽  
Periodic Structures ◽  
Local Density ◽  
Band Gaps ◽  
Basic Unit ◽  
Local Density Of States ◽  
Casimir Forces ◽  
Unit Cells ◽  
The Difference

The Casimir force between inhomogeneous slabs that exhibit a band-like structure is calculated. The slabs are made of basic unit cells each made of two layers of different materials. As the number of unit cells increases the Casimir force between the slabs changes, since the reflectivity develops a band-like structure characterized by frequency regions of high reflectivity. This is also evident in the difference of the local density of states between free and boundary distorted vacuum, that becomes maximum at frequencies corresponding to the band gaps. The calculations are restricted to vacuum modes with wave vectors perpendicular to the slabs.

scholarly journals WHY SCREENING EFFECTS DO NOT INFLUENCE THE CASIMIR FORCE

2009 ◽  
Vol 24 (08n09) ◽  
pp. 1721-1742 ◽  
Author(s):  
V. M. MOSTEPANENKO ◽  
R. S. DECCA ◽  
E. FISCHBACH ◽  
B. GEYER ◽  
G. L. KLIMCHITSKAYA ◽  
...  
Keyword(s):  
Casimir Force ◽  
Charge Carriers ◽  
Reflection Coefficients ◽  
Dispersion Forces ◽  
Physical Reason ◽  
Lifshitz Theory ◽  
Third Law Of Thermodynamics ◽  
Applicability Condition ◽  
And Diffusion

The Lifshitz theory of dispersion forces leads to thermodynamic and experimental inconsistencies when the role of drifting charge carriers is included in the model of the dielectric response. Recently modified reflection coefficients were suggested that take into account screening effects and diffusion currents. We demonstrate that this theoretical approach leads to a violation of the third law of thermodynamics (Nernst's heat theorem) for a wide class of materials and is excluded by the data from two recent experiments. The physical reason for its failure is explained by the violation of thermal equilibrium, which is the fundamental applicability condition of the Lifshitz theory, in the presence of drift and diffusion currents.

scholarly journals Differences in Mathematic Connection Abilities and Self-Efficacy between Students Given Approaches Realistic Mathematics with the Approach Inquiry at Senior High School 2 Tanjung Morawa

2020 ◽  
Vol 3 (3) ◽  
pp. 1489-1500
Author(s):  
Khairina Hazrati ◽  
Ani Minarni ◽  
W. Rajagukguk
Keyword(s):  
High School ◽  
Self Efficacy ◽  
Study Data ◽  
Senior High School ◽  
Literature Study ◽  
Advantages And Disadvantages ◽  
Realistic Mathematics ◽  
Inquiry Approach ◽  
The Difference ◽  
Math Problems

This study aims to determine how the difference between mathematical connections and self-efficacy between students who are given a realistic mathematics approach with an inquiry approach at Senior High School  2 Tanjung Morawa. The sample used in this study was Senior High School  2 Tanjung Morawa. With the method of collecting literature study data. The method used is literature study. The results of this study indicate that the overall approach to mathematics is realistic and inquiry, each of which has advantages and disadvantages, but in this study a good approach to use in students' ability to solve math problems is the inquiry approach, because with the inquiry approach students can be more active, and have ideas in solving math problems.

scholarly journals A novel interestingness measure based on fusion model for association rules mining

2021 ◽  
Vol 336 ◽  
pp. 05009
Author(s):  
Junrui Yang ◽  
Lin Xu
Keyword(s):  
Association Rules ◽  
Negative Association ◽  
Fusion Model ◽  
Interestingness Measures ◽  
Association Rules Mining ◽  
Interestingness Measure ◽  
Advantages And Disadvantages ◽  
Measure Model ◽  
Negative Association Rules ◽  
The Difference

Aiming at the shortcomings of the traditional "support-confidence" association rules mining framework and the problems of mining negative association rules, the concept of interestingness measure is introduced. Analyzed the advantages and disadvantages of some commonly used interestingness measures at present, and combined the cosine measure on the basis of the interestingness measure model based on the difference idea, and proposed a new interestingness measure model. The interestingness measure can effectively express the relationship between the antecedent and the subsequent part of the rule. According to this model, an association rules mining algorithm based on the interestingness measure fusion model is proposed to improve the accuracy of mining. Experiments show that the algorithm has better performance and can effectively help mining positive and negative association rules.

scholarly journals Comparison of the Accuracy and Clinical Parameters of Patient-Specific and Conventionally Bended Plates for Mandibular Reconstruction

2021 ◽  
Vol 11 ◽  
Author(s):  
Henriette L. Möllmann ◽  
Laura Apeltrath ◽  
Nadia Karnatz ◽  
Max Wilkat ◽  
Erik Riedel ◽  
...  
Keyword(s):  
Computer Assisted Surgery ◽  
Reference Points ◽  
Mandibular Reconstruction ◽  
Patient Specific ◽  
Computer Assisted ◽  
Advantages And Disadvantages ◽  
Patient Specific Implants ◽  
Operative Complications ◽  
The Difference ◽  
And Training

ObjectivesThis retrospective study compared two mandibular reconstruction procedures—conventional reconstruction plates (CR) and patient-specific implants (PSI)—and evaluated their accuracy of reconstruction and clinical outcome.MethodsOverall, 94 patients had undergone mandibular reconstruction with CR (n = 48) and PSI (n = 46). Six detectable and replicable anatomical reference points, identified via computer tomography, were used for defining the mandibular dimensions. The accuracy of reconstruction was assessed using pre- and postoperative differences.ResultsIn the CR group, the largest difference was at the lateral point of the condyle mandibulae (D2) -1.56 mm (SD = 3.8). In the PSI group, the largest difference between preoperative and postoperative measurement was shown at the processus coronoid (D5) with +1.86 mm (SD = 6.0). Significant differences within the groups in pre- and postoperative measurements were identified at the gonion (D6) [t(56) = -2.217; p = .031 &lt;.05]. In the CR group, the difference was 1.5 (SD = 3.9) and in the PSI group -1.04 (SD = 4.9). CR did not demonstrate a higher risk of plate fractures and post-operative complications compared to PSI.ConclusionFor reconstructing mandibular defects, CR and PSI are eligible. In each case, the advantages and disadvantages of these approaches must be assessed. The functional and esthetic outcome of mandibular reconstruction significantly improves with the experience of the surgeon in conducting microvascular grafts and familiarity with computer-assisted surgery. Interoperator variability can be reduced, and training of younger surgeons involved in planning can be reaching better outcomes in the future.

PLASMA NEW SELECTIVE PROPERTIES FOR EFFICIENT USE IN ELECTRONICS AND TELECOMMUNICATIONS

2021 ◽  
Vol 2 (64) ◽  
pp. 171-174
Author(s):  
Oleksandr Shefer ◽  
Vitalii Marchenko ◽  
Galina Cherneva
Keyword(s):  
Gaseous Medium ◽  
Charge Carriers ◽  
Practical Implementation ◽  
Large Area ◽  
Elementary Processes ◽  
Molecular Gases ◽  
Radio Signals ◽  
The Difference ◽  
Functional Purpose ◽  
Gas Pressures

In terms of active and passive electronic counteraction, detection of geophysical phenomena of artificial andnatural origin is becoming increasingly important. Discovering new properties of plasma enables to improve the informationcomponent of radio signals more effectively and use the obtained properties in related fields. Elementary processes in thelongitudinal and transverse directions of the discharge, depending on natural and artificial conditions, under different typesof gaseous medium used; at different gas pressures and different pulse-periodic application of an electric field is studied inthe article. The difference of discharge properties in inert and molecular gases with different designs and electrodes of thelaboratory device is shown. It is established that the change of functional purpose between the cathodes and the anodes doesnot change the shape of the discharge. The presence of ambipolar diffusion of charge carriers acting on a large area of plasmawas determined. Partial charge carrier homogeneity has been established, which is observed only along the plasma surface,and homogeneity is violated in the perpendicular direction. The difference in energy input in the discharge, depending on thedesign of the electrodes other things being equal is determined. The identified properties of plasma enable them to be usedmore effectively for practical implementation in the field of electronics and telecommunications and other industries.

The performance of neutron diffractometers at long and short pulse spallation sources: Comparison between ESS and J-PARC

2021 ◽  
pp. 1-18
Author(s):  
Masatoshi Arai ◽  
Ken H. Andersen ◽  
Dimitri N. Argyriou ◽  
Werner Schweika ◽  
Luca Zanini ◽  
...  
Keyword(s):  
Short Pulse ◽  
Source Power ◽  
Advantages And Disadvantages ◽  
Epithermal Neutrons ◽  
Pdf Analysis ◽  
Comparable Performance ◽  
Spallation Source ◽  
The Difference ◽  
Pulse Structure ◽  
Long Pulse

The general performance of diffractometers at the first long pulse spallation source ESS, is compared with their counterparts at J-PARC, a short pulse spallation source. The difference in the inherent pulse structure of these neutron sources presents opportunities for new concepts for instrumentation, where performance does not scale simply with source power. The article describes advantages and disadvantages of those diffractometers, adapting to the very different source characteristics. We find that the two sources offer comparable performance in flux and resolution when operating in high-resolution mode. ESS offers significant advantages in tunability and flexibility, notably in the ability to relax resolution in order to increase flux for a given experiment. The slow repetition rate of ESS favors long instruments. On the other hand, J-PARC instruments perform very well in spite of the lower source power and allow better access to epithermal neutrons, of particular interest for PDF analysis of diffraction data.

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