scholarly journals Mathematical simulation of the processes of two-beam laser controlled thermal-splitting of quartz glass

Doklady BGUIR ◽  
2021 ◽  
Vol 19 (7) ◽  
pp. 80-88
Author(s):  
V. A. Emelyanov ◽  
E. B. Shershnev ◽  
S. I. Sokolov ◽  
A. N. Kupo
Keyword(s):  
Quartz Glass ◽  
Thermal Cracking ◽  
Laser Exposure ◽  
Heat Sources ◽  
Time Intervals ◽  
Beam Laser ◽  
Static Approach ◽  
Parallel Action ◽  
Stable Formation

The paper presents the results of modeling the processes of controlled thermal cracking of quartz glass under the parallel action of two infrared laser beams of different geometries on the material: with maximum intensity in the center and with zero intensity in the center (annular section). To calculate the temperature distribution in the material, the method of Green's functions was used, which allows us to obtain a well-interpreted solution for almost any type of function of surface heat sources. Further, taking into account the quasi-static approach, using the methods of the classical theory of thermoelasticity, thermoelastic microstresses were calculated, both on the surface and in the depth of the material. It is established that the simultaneous use of these two types of laser exposure makes it possible to control the temperature field more efficiently, and create prerequisites for the most stable formation of a microcrack. The simulation results show that with a bi-beam effect, the micromechanical stresses necessary for the formation of a microcrack are realized in shorter time intervals, both on the surface and in the depth of the material, which allows increasing the processing speed by up to 30 %. Strengthening control over the process of controlled thermal cracking can significantly reduce the percentage of defects and improve the quality of the resulting microeletronics products.

Quantitative and Qualitative Characteristics of Urban Discharge to Small River Basins in the South West of Sweden

1983 ◽  
Vol 14 (3) ◽  
pp. 155-166 ◽  
Author(s):  
Wm. Hogland ◽  
R. Berndtsson
Keyword(s):  
River Basins ◽  
Small River ◽  
The South ◽  
Time Intervals ◽  
Qualitative And Quantitative ◽  
South West ◽  
Quantitative Characteristics ◽  
Qualitative Characteristics ◽  
Qualitative And Quantitative Characteristics

The paper deals with the qualitative and quantitative characteristics of urban discharge. Ratios for urban discharge and recipient flow during different time intervals are presented and discussed. The quality of the urban discharge is illustrated through pollutographs.

Analysis of the Test Method of Quartz Glass Optical Homogeneity

2017 ◽  
Vol 726 ◽  
pp. 414-418
Author(s):  
Bo Fu ◽  
Hui Wang ◽  
Zhu Feng Shao
Keyword(s):  
Quartz Glass ◽  
Measurement Accuracy ◽  
Test Methods ◽  
Test Method ◽  
Wavefront Aberration ◽  
Optical Homogeneity ◽  
Advantages And Disadvantages ◽  
Interference Measurement ◽  
Optical Quartz Glass

The optical quartz glass is widely applied in optical system , photo communications，inertial navigation，etc.It must have high optical homogeneity. Optical homogeneity of the optical quartz glass directly affects the wavefront quality of the optical transmission system, and changes the wavefront aberration of the system. How to accurately determine the optical homogeneity of the quartz glass is especially important. Currently，the method of test for optical homogeneity mainly used by interference principle. This paper analyzes various existing interference measurement method and test equipment. Summarized the advantages and disadvantages of various test methods，using range and measurement accuracy.

ENTREPRENEURIAL ACTIVITIES MODELING IN THE HOSPITALITY INDUSTRY BASED ON THE USE OF LAND CADASTRAL VALUATION INDICATORS

2017 ◽  
Author(s):  
Raisa Kozhukhіvska ◽  
◽  
Оlena Sakovska ◽  
Keyword(s):  
Financial Support ◽  
Hospitality Industry ◽  
The State ◽  
Practical Significance ◽  
Time Intervals ◽  
Main Disadvantage ◽  
Entrepreneurial Activities ◽  
The City ◽  
Cluster Level

The article examines the organizational basis of modeling entrepreneurial activities in the hospitality industry based on the use of indicators of cadastral assessment of land. The analysis of practical aspects of updating the results of cadastral assessment of lands of settlements of Cherkassy region has been carried out. It is stated that the cadastral assessment should take into account market situations and trends as much as possible. For the territories of localities the term of actualization in the context of revaluation should be minimum and economically justified. It is designated that the updating of the results of the state cadastral assessment of land requires significant modernization aimed at improving the quality of land assessment work and adequate replenishment of budgets at all levels. The mechanism and features of performance of works on actualization of the state cadastral estimation of the lands of settlements in the territory of Cherkassy region have been analyzed. As a result of the study, it has been found that the main disadvantage of modeling the cadastral assessment of land settlements is: the duration of time intervals between rounds of revaluation, which causes rapid aging of information. The reason for this case is related with the financial support of the works and their scale. Mechanisms for prompt updating of information on the value of land for entrepreneurial activities in the hospitality industry in Cherkassy region have been proposed. The considered method of determining the normative monetary valuation of land takes into account the most important indicators of this industry and is practically significant in collecting information and calculating all indicators in conducting cadastral valuation of land for entrepreneurial activities in the hospitality industry of Cherkassy region. The practical significance of the study is to assess the cadastral condition of land and calculate the specific cadastral value of the city of Uman, as the territory where the hospitality industry is the most developed in Cherkassy region. Due to the clarification of the specific indicator of cadastral value, the price of one square meter of such objects will increase which will allow to proportionally increase the tax component and increase the profitability of budgets at the cluster level

Doping and crystallization of amorphous SiGe films with an excimer (KrF) laser

1995 ◽  
Vol 10 (8) ◽  
pp. 1884-1888 ◽  
Author(s):  
S. Krishnan ◽  
M.I. Chaudhry ◽  
S.V. Babu
Keyword(s):  
Silicon Germanium ◽  
Room Temperature ◽  
Laser Pulses ◽  
Laser Exposure ◽  
Silicon Substrates ◽  
A Value ◽  
Crystal Film ◽  
Krf Laser ◽  
Amorphous Silicon Germanium

Amorphous silicon germanium (a-SiGe) films, deposited on silicon substrates at room temperature in a molecular beam epitaxy system, were transformed into a single-crystal film and doped with phosphorus by exposure to KrF laser pulses. Electron channeling patterns showed that laser exposure resulted in crystallization of the undoped a-SiGe films. The SiGe films were doped by laser irradiation, using a phosphorus spin-on-dopant. The sheet resistance of the doped films decreased with increasing numbers of pulses, reaching a value of about ∼ 5 × 104 ohms/□ after 15 pulses. I-V data from mesa-type n-SiGe/p-Si diode devices were used to determine the effect of laser processing on the quality of the SiGe films.

Effect of agglomeration purification of quartz powders on the quality of quartz glass

2009 ◽  
Vol 66 (11-12) ◽  
pp. 403-404
Author(s):  
R. Sh. Nasyrov ◽  
A. S. Lebedev ◽  
R. T. Zainullina
Keyword(s):  
Quartz Glass

scholarly journals Alternative solid fuels combustion in small heat source

2018 ◽  
Vol 168 ◽  
pp. 08002 ◽  
Author(s):  
Michal Holubčík ◽  
Nikola Kantová ◽  
Jozef Jandačka ◽  
Zuzana Kolková
Keyword(s):  
Heat Source ◽  
Alternative Fuels ◽  
Beech Wood ◽  
Major Influence ◽  
Heat Output ◽  
Heat Sources ◽  
Gaseous Emissions ◽  
Output Efficiency ◽  
Negative Factors

Air quality is related to the using of solid fuel based heat sources in which the human factor has a major influence on the quality of combustion, which can lead to higher emissions into the air. One of the negative factors is the use of alternative fuels in heat sources. The article deals with the combustion of various alternative fuels, on a waste basis, in small heat sources. There were tested 4 types of fuels: beech wood pieces, 2 types of solid alternative fuel on the base of municipal waste and wood waste. In the experiment, it was tested the influence of used fuel in the fireplace on the heat output, efficiency, production of gaseous emissions and particulate matter. The results confirmed that combustion of fuels not recommended by the heat source manufacturer reduces the efficiency of combustion and significantly increases all monitored emissions.

scholarly journals The Effect of Probabilistic Information on Threshold Forecasts

2007 ◽  
Vol 22 (4) ◽  
pp. 804-812 ◽  
Author(s):  
Susan Joslyn ◽  
Karla Pak ◽  
David Jones ◽  
John Pyles ◽  
Earl Hunt
Keyword(s):  
General Tendency ◽  
Laboratory Setting ◽  
Time Intervals ◽  
Probabilistic Information ◽  
Within Subjects ◽  
Low Probability ◽  
The Difference ◽  
High Winds ◽  
Very High

Abstract The study reported here asks whether the use of probabilistic information indicating forecast uncertainty improves the quality of deterministic weather decisions. Participants made realistic wind speed forecasts based on historical information in a controlled laboratory setting. They also decided whether it was appropriate to post an advisory for winds greater than 20 kt (10.29 m s−1) during the same time intervals and in the same geographic locations. On half of the forecasts each participant also read a color-coded chart showing the probability of winds greater than 20 kt. Participants had a general tendency to post too many advisories in the low probability situations (0%–10%) and too few advisories in very high probability situations (90%–100%). However, the probability product attenuated these biases. When participants used the probability product, they posted fewer advisories when the probability of high winds was low and they posted more advisories when the probability of high winds was high. The difference was due to the probability product alone because the within-subjects design and counterbalancing of forecast dates ruled out alternative explanations. The data suggest that the probability product improved threshold forecast decisions.

scholarly journals Improved Wait Time Intervals for Prostate Cancer Patients in a Multi-Disciplinary Rapid Diagnostic Unit Compared to a Community-Based Referral Pattern

2013 ◽  
Vol 7 (7-8) ◽  
pp. 244 ◽  
Author(s):  
Perakaa Sethukavalan ◽  
Liying Zhang ◽  
Vibhuti Jethava ◽  
Christiaan Stevens ◽  
Stanley Flax ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cancer Patients ◽  
Community Setting ◽  
Wait Time ◽  
Structured Interview ◽  
Risk Category ◽  
Time Intervals ◽  
Diagnostic Unit ◽  
Chart Abstraction

Background: Wait times in cancer diagnosis and treatment may significantly affect a patient’s treatment outcome, prognosis and quality of life. The purpose of this study was to capture wait time intervals for patients with prostate cancer treated with radiotherapy (RT) at the Odette Cancer Centre, Toronto, Ontario, Canada and to compare patients diagnosed in a rapid diagnostic unit (RDU) versus the usual community referral process.Methods: Patients agreed to participate in the study during their RT planning sessions. A semi-structured interview and chart abstraction was conducted to record key wait time milestones.Results: A total of 87 patients participated in the study: 44 RDU patients and 43 community patients. The median overall wait time intervals from suspicion of prostate cancer to RT was 138 and 183 days, respectively (p = 0.046). There were statistically significant differences observed for other key wait time intervals favouring the RDU cohort: suspicion to decision-to-treat (DTT; p = 0.012), urologist visit to diagnosis (p = 0.0094), diagnosis to DTT (p = 0.018), and diagnosis to treatment (p = 0.016). Risk category and Gleason sum was independently predictive of longer intervals from diagnosis to DTT.Interpretation: Wait time intervals from suspicion to treatment are significantly shorter for prostate cancer patients in 2011 to 2012 than in 2003 when patients were diagnosed and referred in the community setting. A prostate-specific RDU further reduced a number of key wait time intervals supporting more multidisciplinary RDUs for common diseases. Further work needs to be done to identify why delays are occurring and to develop new processes to minimize delays.

Image processing algorithms in the assessment of grain damage degree

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Wojciech Maliga ◽  
Włodzimierz Dudziński ◽  
Magdalena Łabowska ◽  
Jerzy Detyna ◽  
Marcin Łopusiewicz ◽  
...  
Keyword(s):  
Image Processing ◽  
Cross Sections ◽  
Three Dimensional ◽  
Sample Volume ◽  
Three Dimensional Model ◽  
Time Intervals ◽  
Damage Degree ◽  
Grain Damage ◽  
Analyse Sample

Abstract Objectives The paper presents preliminary results on the assessment of algorithms used in image processing of the grain damage degree. The purpose of the work is developing a tool allowing to analyse sample cross-sections of rye germs. Methods The analysis of the grain cross-sections was carried out on the basis of a series their photos taken at equal time intervals at a set depth. The cross-sections will be used to create additional virtual cross-sections allowing to analyse the whole sample volume. The ultimate plan is to generate two cross-sections perpendicular to each other. Based on volumetric data read from the sample section, a three-dimensional model of an object will be generated. Results The analysis of model surface will allowed us to detect possible grain damage. The developed method of preparing the research material and the proprietary application allowed for the identification of internal defects in the biological material (cereal grains). Conclusions The presented methodology may be used in the agri-food industry in the future. However, much research remains to be done. These works should primarily aim at significantly reducing the time-consuming nature of individual stages, as well as improving the quality of the reconstructed image.

Laser Modification of Leather and Fur Surface to Improve Its Quality when Conducting Finishing Operations

2020 ◽  
Vol 20 (4) ◽  
pp. 353-360
Author(s):  
Akmal Yusupovich TOSHEV ◽  
Mariya Ivanovna MARKEVICH ◽  
Tulkin Jumayevich KODIROV ◽  
Valentina Illarionovna ZHURAVLEVA
Keyword(s):  
Chemical Modification ◽  
Laser Treatment ◽  
Laser Processing ◽  
Collagen Fibers ◽  
Laser Exposure ◽  
Laser Modification ◽  
Treatment Changes ◽  
Configuration Changes

The article discusses the problems of activation of the surface of the leather tissue by laser exposure, changes in the morphology of the surface of the leather tissue during laser processing, and subsequent covering dyeing of the leather. It is shown that laser treatment changes the structure of the surface of the leather tissue, the bundles of collagen fibers are split, the structure becomes loose, which increases the diffusion of the coating dye reagents, and their reactivity increases without chemical modification. In the process of grinding leather fabric, it is finely cleaned which improves adhesion of the coating paint to the surface of the leather fabric, which improves the quality of leather fabric products. It was shown that laser exposure under the conditions found (pulses with an interval of 3 μs, a duration of 10 ns) does not cause destruction and configuration changes in collagen.

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