Study of Affecting Parameters in Laser Hole Drilling of Sheet Metals

1987 ◽  
Vol 109 (4) ◽  
pp. 282-287 ◽  
Author(s):  
Bekir Sami Yilbas
Keyword(s):  
Physical Properties ◽  
Laser Drilling ◽  
Hole Drilling ◽  
Main Process ◽  
Workpiece Material ◽  
Practical Applications ◽  
Laser Parameters ◽  
Four Blocks ◽  
Four Levels

In practical applications of laser drilling the quality of the drilled hole is the critical factor, and recently methods of studying the influence on quality of the main process variables have been developed, which seek to improve quality rather than explain the drilling mechanism. Hole quality can be judged by: internal form and taper and related geometrical features, and the extent of heat affected materials. The optimum performance in laser drilling depends very much upon the proper selection of laser parameters as well as the physical properties of the workpiece material. With so many variables, and incomplete knowledge of the relationships between them, statistical methods are needed to design experiments and analyze the results. In the present work five factors at four levels were considered. Four factors are given quantative; one, the material specification, is qualitative. The result is that the design has four blocks indentified with materials each of which can be treated as a complete factorial design. However, the materials can be described quantitatively by their physical properties, so the results were correlated with the groups generated by the dimensional analysis. It is observed that main effects of laser parameters as well as their interactions, have significant effects on all features of hole geometry. Drilling medium pressure was found to be very effective factor, since its interactions with the other parameters in any order are significant.

A unified framework for automated person re-indentification

2020 ◽  
Vol 71 (7) ◽  
pp. 868-880
Author(s):  
Nguyen Hong-Quan ◽  
Nguyen Thuy-Binh ◽  
Tran Duc-Long ◽  
Le Thi-Lan
Keyword(s):  
Deep Learning ◽  
Video Analysis ◽  
Camera Network ◽  
Unified Framework ◽  
Person Detection ◽  
Practical Applications ◽  
Detection And Tracking ◽  
Analysis System ◽  
Bounding Boxes

Along with the strong development of camera networks, a video analysis system has been become more and more popular and has been applied in various practical applications. In this paper, we focus on person re-identification (person ReID) task that is a crucial step of video analysis systems. The purpose of person ReID is to associate multiple images of a given person when moving in a non-overlapping camera network. Many efforts have been made to person ReID. However, most of studies on person ReID only deal with well-alignment bounding boxes which are detected manually and considered as the perfect inputs for person ReID. In fact, when building a fully automated person ReID system the quality of the two previous steps that are person detection and tracking may have a strong effect on the person ReID performance. The contribution of this paper are two-folds. First, a unified framework for person ReID based on deep learning models is proposed. In this framework, the coupling of a deep neural network for person detection and a deep-learning-based tracking method is used. Besides, features extracted from an improved ResNet architecture are proposed for person representation to achieve a higher ReID accuracy. Second, our self-built dataset is introduced and employed for evaluation of all three steps in the fully automated person ReID framework.

Pengaruh Penambahan Air pada Pengolahan Susu Kedelai

2015 ◽  
Vol 4 (1) ◽  
pp. 8-13
Author(s):  
Priscillia Picauly ◽  
Josefina Talahatu ◽  
Meitycorfrida Mailoa
Keyword(s):  
Glycine Max ◽  
Physical Properties ◽  
Sweet Taste ◽  
Soya Milk ◽  
Randomized Design ◽  
Soybean Extract ◽  
Glycine Max L ◽  
Completely Randomized Design ◽  
Water Ratio

Soybean (Glycine max (L) Merr) is needed as an alternative diversification in order to increase protein consumption. Soybean can be processed into variety of foods and drinks. The most popular drink from soybean is soya milk which is made from soybean extract yielded from the addition of water. The amount of water added determine the quality of soya milk due to its effect on the chemical and physical properties of soya milk. This research was intended to find out the proper ratio of soybean and water in the processing of soya milk to yield the best quality. A completely randomized design was used with eight treatments of soybean and water ratio as follows, ratio of 1 : 6, ratio of 1 : 8, ratio of 1 : 10, ratio of 1 : 12, ratio of 1 : 14, ratio of 1 : 16, ratio of 1 : 18 and ratio of 1 : 20. Result showed the soybean and water ratio 1 : 10 in the processing of soya milk yielded milk having good quality according to its chemical with protein content of 2.53%, fat of 1.20%, sugar total of 1.60%, pH of 7.1, and organoleptic characteristies of both somewhat sweet taste and viscous texture.

PENGARUH KONSENTRASI RAGI Saccharomyces cerevisiae DAN LAMA FERMENTASI TERHADAP KUALITAS CUKA TOMI-TOMI (Flacourtia inermis)

2015 ◽  
Vol 4 (2) ◽  
pp. 50-55
Author(s):  
Sandra J Nendissa ◽  
Rachel Breemer ◽  
Nikholaus Melamas
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Experimental Design ◽  
Total Dissolved Solids ◽  
Total Sugar ◽  
Dissolved Solids ◽  
Randomized Experimental Design ◽  
Two Factors ◽  
Four Levels

This objectives of this research were both to study and determine the best level of concentration of yeast Saccharomyces cereviseae and period of fermentation on the quality of tomi-tomi vinegar (Flacourtia inermis). A completely randomized experimental design with two factors of treatment was applied in this research. The first factor was concentration of yeast S. cereviseae having four levels of tretament, i.e.: without the addition of yeast 0.5, 1 and 1.5 g yeast. The second factor was period fermentation with 1, 2, 3, 4, and 5 weeks. The result indicated that the concentration of yeast S. cereviseae 1.5 g and period fermentation 5 week produced a good tomi-tomi vinegar with total acids 51.22%, total dissolved solids 8.35, total sugar 8.07% and pH 5.40.

KARAKTERISTIK FISIK BUBUR INSTAN TERSUBTITUSI TEPUNG PISANG TONGKA LANGIT

2015 ◽  
Vol 4 (2) ◽  
pp. 41-44
Author(s):  
Priscillia Picauly ◽  
Gilian Tetelepta
Keyword(s):  
Water Solubility ◽  
Physical Property ◽  
Rice Flour ◽  
Absorption Index ◽  
Randomized Design ◽  
Nutrition Value ◽  
Banana Flour ◽  
Completely Randomized Design ◽  
Four Levels

Instant porridge is sereal-based food that can be combined with fruits so it will contain better nutrition. To improve the nutrition value of instant porridge then substitute of one kind of banana originally from Maluku is Tongka langit banana. A good quality of instant porridge has a high nutrition and a best physical property. This research aims to characterize of the physical properties instant porridge that are substituted by Tongka langit banana flour and the rice flour. The design that is applied is completely randomized design with four levels of treatment in comparing the substitution between Tongka langit banana flour and the rice flour as follow 20%, 40%, 60% and 80%. According to the result of this research, the physical characteristic of instant porridge that are substituted by Tongka langit banana flour are bulk density (0.84-0.89 g/mL), water absorption index (3.49-4.05%), and water solubility index (0.02-0.04%).

scholarly journals Analyzing the Effects of the Kinematic System on the Quality of Holes Drilled in 42CrMo4 + QT Steel

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4046
Author(s):  
Mateusz Bronis ◽  
Edward Miko ◽  
Lukasz Nowakowski
Keyword(s):  
Cutting Speed ◽  
Hole Drilling ◽  
Internal Cooling ◽  
Hole Quality ◽  
The Third ◽  
Kinematic System ◽  
Turning Center ◽  
Dimensional Errors ◽  
The Relationship

This article discusses the relationship between the kinematic system used in drilling and the quality of through-holes. The drilling was done on a CTX Alpha 500 universal turning center using a TiAlN-coated 6.0 mm drill bit with internal cooling, mounted in a driven tool holder. The holes were cut in cylindrical 42CrMo4 + QT steel samples measuring 30 mm in diameter and 30 mm in length. Three types of hole-drilling kinematic systems were considered. The first consisted of a fixed workpiece and a tool performing rotary (primary) and linear motions. In the second system, the workpiece rotated (primary motion) while the tool moved linearly. In the third system, the workpiece and the tool rotated in opposite directions; the tool also moved linearly. The analysis was carried out for four output parameters characterizing the hole quality (i.e., cylindricity, straightness, roundness, and diameter errors). The experiment was designed using the Taguchi approach (orthogonal array). ANOVA multi-factor statistical analysis was used to determine the influence of the input parameters (cutting speed, feed per revolution and type of kinematic system) on the geometrical and dimensional errors of the hole. From the analysis, it is evident that the kinematic system had a significant effect on the hole roundness error.

scholarly journals Femtosecond Laser Drilling of Cylindrical Holes for Carbon Fiber-Reinforced Polymer (CFRP) Composites

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2953
Author(s):  
Hao Jiang ◽  
Caiwen Ma ◽  
Ming Li ◽  
Zhiliang Cao
Keyword(s):  
Carbon Fiber ◽  
Femtosecond Laser ◽  
Picosecond Laser ◽  
Laser Drilling ◽  
Fiber Reinforced Polymer ◽  
Carbon Fiber Reinforced Polymer ◽  
Laser Parameters ◽  
Reinforced Polymer ◽  
Cfrp Composites ◽  
Cylindrical Holes

Ultrafast laser drilling has been proven to effectively reduce the heat-affected zone (HAZ) of carbon fiber-reinforced polymer (CFRP) composites. However, previous research mainly focused on the effects of picosecond laser parameters on CFRP drilling. Compared with a picosecond laser, a femtosecond laser can achieve higher quality CFRP drilling due to its smaller pulse width, but there are few studies on the effects of femtosecond laser parameters on CFRP drilling. Moreover, the cross-sectional taper of CFRP produced by laser drilling is very large. This paper introduces the use of the femtosecond laser to drill cylindrical holes in CFRP. The effect of laser power, rotational speed of the laser, and number of spiral passes on HAZ and ablation depth in circular laser drilling and spiral laser drilling mode was studied, respectively. It also analyzed the forming process of the drilling depth in the spiral drilling mode and studied the influence of laser energy and drilling feed depth on the holes’ diameters and the taper. The experimental results show that the cylindrical hole of CFRP with a depth-to-diameter ratio of about 3:1 (taper < 0.32∘, HAZ < 10 m) was obtained by using femtosecond laser and a spiral drilling apparatus.

scholarly journals Molecular Responses during Plant Grafting and Its Regulation by Auxins, Cytokinins, and Gibberellins

Biomolecules ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 397 ◽  
Author(s):  
Anket Sharma ◽  
Bingsong Zheng
Keyword(s):  
Plant Hormones ◽  
Growth And Development ◽  
Molecular Mechanisms ◽  
Main Process ◽  
Graft Union ◽  
Physiological Processes ◽  
Current Review ◽  
Postharvest Life ◽  
Successful Production

Plant grafting is an important horticulture technique used to produce a new plant after joining rootstock and scion. This is one of the most used techniques by horticulturists to enhance the quality and production of various crops. Grafting helps in improving the health of plants, their yield, and the quality of plant products, along with the enhancement of their postharvest life. The main process responsible for successful production of grafted plants is the connection of vascular tissues. This step determines the success rate of grafts and hence needs to be studied in detail. There are many factors that regulate the connection of scion and stock, and plant hormones are of special interest for researchers in the recent times. These phytohormones act as signaling molecules and have the capability of translocation across the graft union. Plant hormones, mainly auxins, cytokinins, and gibberellins, play a major role in the regulation of various key physiological processes occurring at the grafting site. In the current review, we discuss the molecular mechanisms of graft development and the phytohormone-mediated regulation of the growth and development of graft union.

Separation Standards—II

1966 ◽  
Vol 19 (2) ◽  
pp. 169-186 ◽  
Author(s):  
P. G. Reich
Keyword(s):  
One Dimension ◽  
Collision Risk ◽  
Practical Applications ◽  
Upper Limit ◽  
Intensive Observation ◽  
Relative Errors ◽  
Separation Standards

In the first part of this series of papers an outline was given of the approach made at the Royal Aircraft Establishment to the problems of estimating collision risk and of specifying the quality of navigation needed to make separation standards safe. It was stressed that estimates should be based on intensive observation of flying errors, rather than on speculative theories, and that it is more feasible to develop ‘upper limit’ estimating techniques than those which purport to give the exact risk. In summary, a list of seven ‘requirements’ was given, as a reminder of the essential principles which can so easily be overlooked in the piecemeal task of relating separation standards to collision risk.The purpose of this paper is to show some of the theoretical techniques which have been developed at R.A.E. to satisfy five of these requirements. (The remaining two do not call for special techniques and will be dealt with when practical applications are described in Part III.) The paper contains three Appendixes, dealing with the frequency of losing separation in one dimension, the computation of P's from the assumed tail shapes, and the treatment of relative errors. These are not included here but will appear in the off-printed version which may be obtained from the Royal Aircraft Establishment.Both this paper and the paper that follows by Mr. Attwooll are crown copyright and are reproduced with the permission of H.M. Stationery Office.

scholarly journals Synergetic Use of Sentinel-1 and Sentinel-2 Data for Soil Moisture Mapping at Plot Scale

2018 ◽  
Vol 10 (8) ◽  
pp. 1285 ◽  
Author(s):  
Reza Attarzadeh ◽  
Jalal Amini ◽  
Claudia Notarnicola ◽  
Felix Greifeneder
Keyword(s):  
Soil Moisture ◽  
Optical Data ◽  
Estimation Accuracy ◽  
Support Vector ◽  
Practical Applications ◽  
Initial Stage ◽  
Object Based ◽  
Single Polarization ◽  
Selection Of

This paper presents an approach for retrieval of soil moisture content (SMC) by coupling single polarization C-band synthetic aperture radar (SAR) and optical data at the plot scale in vegetated areas. The study was carried out at five different sites with dominant vegetation cover located in Kenya. In the initial stage of the process, different features are extracted from single polarization mode (VV polarization) SAR and optical data. Subsequently, proper selection of the relevant features is conducted on the extracted features. An advanced state-of-the-art machine learning regression approach, the support vector regression (SVR) technique, is used to retrieve soil moisture. This paper takes a new look at soil moisture retrieval in vegetated areas considering the needs of practical applications. In this context, we tried to work at the object level instead of the pixel level. Accordingly, a group of pixels (an image object) represents the reality of the land cover at the plot scale. Three approaches, a pixel-based approach, an object-based approach, and a combination of pixel- and object-based approaches, were used to estimate soil moisture. The results show that the combined approach outperforms the other approaches in terms of estimation accuracy (4.94% and 0.89 compared to 6.41% and 0.62 in terms of root mean square error (RMSE) and R2), flexibility on retrieving the level of soil moisture, and better quality of visual representation of the SMC map.

Morphological traits of the development of the skin and wool cover in sheep of Prikatunsky meat and wool type

2021 ◽  
pp. 60-68
Author(s):  
I. I. Dmitrik ◽  
G. V. Zavgorodnyaya ◽  
M. I. Pavlova ◽  
N. A. Podkorytov
Keyword(s):  
Physical Properties ◽  
Morphological Traits ◽  
Age Groups ◽  
Body Side ◽  
Low Level ◽  
Research Material ◽  
High Level ◽  
Significant Factors

A large number of works are devoted to the development of the skin and hair cover of sheep, depending on their breed affiliation, age, feeding conditions and housing. The authors point out that along with other conditions the quality of wool and wool clip is greatly influenced by the conditions of the feeding of animals. A high level of feeding increases the wool clip and improves the quality of the wool and vice versa a low level reduces, causes thinning and worsens other physical properties of the wool. As is known, one of the significant factors that determine the increase in wool clip is the size of the animal and, consequently, the total area of the skin. The purpose of the research was to investigate the morphological traits of the development of the skin and wool cover in sheep of Prikatunsky meat and wool type. The research material was wool samples from four topographic areas of the animal’s body (side/thigh/back/belly) and skin (side) of different sex and age groups, selected from the animals of the studied groups. In the course of research, the quality of wool and indicators of the histostructure of the skin of Prikatunsky meat and wool type of sheep have been investigated. In terms of thick-haired of wool, replacement rams and gimbers of Prikatunsky meat and wool type of sheep were superior by 4,82 pcs. per mm² or 19,0 % and 4,41 pcs. per mm² or 15,8 % of adult animals, respectively. Balance secondary follicles/primary follicles in young animals were higher by 10,3 and 17,3 % compared to breeding rams and ewes. The wool of the replacement young animals was thinner by 7,28 and 4,78 microns and they were more thick-haired. The obtained data will be used in the mating campaign when mating program rams in order to improve the sheep of Prikatunsky meat and wool type.

Sign in / Sign up

Export Citation Format

Share Document