scholarly journals Lance Design for Scrap Melting Aggregates

2021 ◽  
Vol 15 (1) ◽  
pp. 162-167
Author(s):  
Ladislav Kovar ◽  
Pavel Novak ◽  
Tomas Hapla
Keyword(s):  
Operational Reliability ◽  
Bath Surface ◽  
Scrap Melting ◽  
Gaseous Media ◽  
Design Systems ◽  
Design Characteristics ◽  
The Individual ◽  
Long Term Experience

Metallurgical aggregates, which are used for metal waste melting, are equipped with lances for blowing gaseous media. These gaseous media allow especially scrap melting and intense homogenization of the resulting melt. In connection with this, the blowing systems are developed both for blowing of gaseous media itself on the bath surface or into the melt and for blowing of the gas mixture with powdered substances. When designing the blowing systems and the individual lance tips and nozzles, it is necessary to respect certain criteria, the derivation of which is based on long-term experience and acquired knowledge in this field. The submitted paper summarizes the design recommendations, including the determination of the selected design characteristics of the nozzles for blowing gaseous media on the bath surface in the metallurgical aggregate. These design characteristics help designers and engineers to design systems that meet the high demands on quality, efficiency and operational reliability.

scholarly journals Visualizing the Bohr effect in hemoglobin: neutron structure of equine cyanomethemoglobin in the R state and comparison with human deoxyhemoglobin in the T state

2016 ◽  
Vol 72 (7) ◽  
pp. 892-903 ◽  
Author(s):  
Steven Dajnowicz ◽  
Sean Seaver ◽  
B. Leif Hanson ◽  
S. Zoë Fisher ◽  
Paul Langan ◽  
...  
Keyword(s):  
Structural Changes ◽  
Accurate Determination ◽  
Bohr Effect ◽  
Salt Bridges ◽  
Histidine Residues ◽  
Regions Of Stability ◽  
The Individual ◽  
T State

Neutron crystallography provides direct visual evidence of the atomic positions of deuterium-exchanged H atoms, enabling the accurate determination of the protonation/deuteration state of hydrated biomolecules. Comparison of two neutron structures of hemoglobins, human deoxyhemoglobin (T state) and equine cyanomethemoglobin (R state), offers a direct observation of histidine residues that are likely to contribute to the Bohr effect. Previous studies have shown that the T-state N-terminal and C-terminal salt bridges appear to have a partial instead of a primary overall contribution. Four conserved histidine residues [αHis72(EF1), αHis103(G10), αHis89(FG1), αHis112(G19) and βHis97(FG4)] can become protonated/deuterated from the R to the T state, while two histidine residues [αHis20(B1) and βHis117(G19)] can lose a proton/deuteron. αHis103(G10), located in the α1:β1dimer interface, appears to be a Bohr group that undergoes structural changes: in the R state it is singly protonated/deuterated and hydrogen-bonded through a water network to βAsn108(G10) and in the T state it is doubly protonated/deuterated with the network uncoupled. The very long-term H/D exchange of the amide protons identifies regions that are accessible to exchange as well as regions that are impermeable to exchange. The liganded relaxed state (R state) has comparable levels of exchange (17.1% non-exchanged) compared with the deoxy tense state (T state; 11.8% non-exchanged). Interestingly, the regions of non-exchanged protons shift from the tetramer interfaces in the T-state interface (α1:β2and α2:β1) to the cores of the individual monomers and to the dimer interfaces (α1:β1and α2:β2) in the R state. The comparison of regions of stability in the two states allows a visualization of the conservation of fold energy necessary for ligand binding and release.

scholarly journals CALIBRATION AND STABILITY ANALYSIS OF THE VLP-16 LASER SCANNER

2016 ◽  
Vol XL-3/W4 ◽  
pp. 55-60 ◽  
Author(s):  
C. L. Glennie ◽  
A. Kusari ◽  
A. Facchin
Keyword(s):  
Stability Analysis ◽  
Point Cloud ◽  
Temporal Stability ◽  
Laser Scanner ◽  
Effect Of Temperature ◽  
Geometric Calibration ◽  
Long Term Stability ◽  
The Individual

We report on a calibration and stability analysis of the Velodyne VLP-16 LiDAR scanner. The sensor is evaluated for long-term stability, geometric calibration and the effect of temperature variations. To generalize the results, three separate VLP-16 sensors were examined. The results and conclusions from the analysis of each of the individual sensors was similar. We found that the VLP-16 showed a consistent level of performance, in terms of range bias and noise level over the tested temperature range from 0–40 °C. A geometric calibration was able to marginally improve the accuracy of the VLP-16 point cloud (by approximately 20%) for a single collection, however the temporal stability of the geometric calibration negated this accuracy improvement. Overall, it was found that there is some long-term walk in the ranging observations from individual lasers within the VLP-16, which likely causes the instability in the determination of geometric calibration parameters. However, despite this range walk, the point cloud delivered from the VLP-16 sensors tested showed an accuracy level within the manufacturer specifications of 3 cm RMSE, with an overall estimated RMSE of range residuals between 22 mm and 27 mm.

scholarly journals DETERMINATION OF PERSONAL SIGNIFICANCE AND CONTENT OF VALUES

2020 ◽  
Vol 8 (4) ◽  
pp. 445-455
Author(s):  
A.M. Lesin ◽  
Keyword(s):  
Semantic Content ◽  
Test Methods ◽  
Self Reflection ◽  
Personal Significance ◽  
Scientific Schools ◽  
The Social ◽  
Psychological Structure ◽  
Long Term Experience

This article poses a problem associated with the difficulties of studying and identifying the motivational potential of the value sphere, as well as the discrepancy between the content of the same values in different people or in the same, but at different times. The article describes the results of a theoretical search associated with different approaches to understanding and studying values in different sciences and scientific schools. Also, the main variants of classifications of values and the ways of their formation in the direction of the personality in the process of ontogenesis are determined. The difficulties associated with the study of values with the help of tests, taking into account the social desirability and expectation of answers or the lack of self-reflection ability of the respondents, are described. The modern non-test methods and approaches to the study of the value sphere are analyzed, which make it possible to identify personally significant values and the level of their motivational potential. A method is proposed for determining the personal significance of values , as opposed to their reflec tive representation, using the magnitude of the conflict between the significance and the implementation of values. The long-term experience of using this method among various respondents is described. Variants of the destructive level of personal significance of some values are demonstrated. The possibilities and examples of the study of values in relation to the psychological structure of initiative are shown. The possibilities of content analysis in determining the content are illustrated, examples of different semantic content of the same values are given. It is concluded that, in addition to classical test methods, it is necessary to apply such methods as well, which will help to distinguish between value ideas and personal values proper, as well as to determine their content.

scholarly journals A Systems Thinking Model to Support Long-Term Bearability of the Healthcare System: The Case of the Province of Quebec

2019 ◽  
Vol 11 (24) ◽  
pp. 7028 ◽  
Author(s):  
Ernesto A. Lagarda-Leyva ◽  
Angel Ruiz
Keyword(s):  
Social Services ◽  
Decision Making Process ◽  
Analysis Tool ◽  
Health And Social Services ◽  
Causal Diagrams ◽  
The Individual ◽  
System 1 ◽  
Excellent Tool

This paper describes the modeling efforts devoted by the Ministry of Health and Social Services of Québec, Canada (MSSS), to ensure the long-term bearability of their care system. To this end, it studies the relationships between four entities that self-regulate and interact to form the complex care-providing system: (1) universities; (2) hospitals and doctors; (3) the ministry; and (4) society. The first phase of this research focuses on modeling such relationships and relies on the system dynamics methodology to adequately capture the long-term dynamics of the system. The methodology encompasses three phases: (a) determination of the critical variables and parameters of each entity; (b) development of the causal diagram of each entity; and (c) integration of the individual causal diagrams to form the global system diagram. The final casual model illustrates and explains the relationships between all the entities and constitutes an excellent tool to support experts during discussions or focus groups where critical variables that positively or negatively affect the system can be evaluated. We intend to enrich this casual model in a further phase of the project, which will hopefully lead to a simulation and scenario analysis tool that can be used to support managers in their long-term decision-making process.

Personality-Oriented Model in the Preparation of an Engineer-Teacher

2020 ◽  
Vol 8 (1) ◽  
pp. 22-29
Author(s):  
Marina Nikolova
Keyword(s):  
Professional Qualification ◽  
Complex Combination ◽  
Comprehensive Manner ◽  
The Individual ◽  
Long Term Experience

The scope and content of the profession "an engineer with professional qualification for teaching" should be considered as a complex combination of engineering, psycho-pedagogical and methodological components. The ability to absorb them in a quality way will enable the individual, to a certain extent to perform the functions assigned to him in a more comprehensive manner. The question "What is the pedagogical essence of the profession" engineer-teacher?” is extremely important in that relation. Long-term experience in the preparation of such specialists allowed the the formation of a specific Person-oriented model that reveals the pedagogical essence of this process. In current articles presents the structure and its development.

scholarly journals Investigating Greenland's glaciers

1990 ◽  
Vol 148 ◽  
pp. 46-51
Author(s):  
A Weidick
Keyword(s):  
Point Of View ◽  
Short Term ◽  
Glacier Fluctuations ◽  
Glacier Changes ◽  
Future Events ◽  
Global Sea Level ◽  
The Individual ◽  
The Impact

Investigations of Greenland's glaciers undertaken by GGU are primarily related to the exploitation of meltwater from the Inland lce and local glaciers in western Greenland, i.e. they are essentially related to glacier hydrology (Olesen & Braithwaite, 1989). The studies are therefore based on mass balance data combined with investigations of superglacial melt/refreezing and the determination of the internal mode of drainage. Related to this work is the documentation of short-term glacier changes at specific localities identified as being of special interest for hydropower from the point of view of glacier hazards, i.e. for example damage caused by tapping of ice dammed lakes or change of proglacial draining caused by change in the glacier's thickness and extent. Similar documentation of long-term glacier fluctuations provides a background for control and modelling of past glacier fluctuations. The procedures have a direct bearing on the calculation of scenarios for future events related to the individual localities or, in a regional sense, to the impact of changes in Greenland glaciers on global sea level (the 'greenhouse effect’).

Rheological Measurements for the Characterization of High Polymers

1958 ◽  
Vol 31 (4) ◽  
pp. 681-690 ◽  
Author(s):  
Kurt Edelmann ◽  
Edith Horn
Keyword(s):  
Flow Curve ◽  
Scientific Practice ◽  
Flow Behavior ◽  
Material Constant ◽  
Absolute Value ◽  
Long Term Experience ◽  
High Polymers

Abstract Since the Umstätter structural viscometer represents the only viscometer that operates on the capillary principle, the most accurate measuring principle in viscometry, with a shear stress range above 104, this paper describes the necessary steps, from the long term experience of the authors with this apparatus, which permit a rapid and true determination of a complete flow curve. Also the necessary calculations are given and explained in an example. From this method, the critical velocity gradient G^, the inflection point of the flow curve, was obtained as a characteristic material constant, dependent only on the molecular weight of the high polymer and its absolute value for inhomogeneity. It is the hope of the authors that scientific practice for characterizing high polymers will increasingly refer to the flow behavior of (their) solutions by determining the flow curve.

scholarly journals CALIBRATION AND STABILITY ANALYSIS OF THE VLP-16 LASER SCANNER

2016 ◽  
Vol XL-3/W4 ◽  
pp. 55-60 ◽  
Author(s):  
C. L. Glennie ◽  
A. Kusari ◽  
A. Facchin
Keyword(s):  
Stability Analysis ◽  
Point Cloud ◽  
Temporal Stability ◽  
Laser Scanner ◽  
Effect Of Temperature ◽  
Geometric Calibration ◽  
Long Term Stability ◽  
The Individual

We report on a calibration and stability analysis of the Velodyne VLP-16 LiDAR scanner. The sensor is evaluated for long-term stability, geometric calibration and the effect of temperature variations. To generalize the results, three separate VLP-16 sensors were examined. The results and conclusions from the analysis of each of the individual sensors was similar. We found that the VLP-16 showed a consistent level of performance, in terms of range bias and noise level over the tested temperature range from 0–40 °C. A geometric calibration was able to marginally improve the accuracy of the VLP-16 point cloud (by approximately 20%) for a single collection, however the temporal stability of the geometric calibration negated this accuracy improvement. Overall, it was found that there is some long-term walk in the ranging observations from individual lasers within the VLP-16, which likely causes the instability in the determination of geometric calibration parameters. However, despite this range walk, the point cloud delivered from the VLP-16 sensors tested showed an accuracy level within the manufacturer specifications of 3 cm RMSE, with an overall estimated RMSE of range residuals between 22 mm and 27 mm.

Preparation And elemental analysis of ancient fibers

1987 ◽  
Vol 45 ◽  
pp. 410-411
Author(s):  
Allen Angel ◽  
Kathryn A. Jakes
Keyword(s):  
Cross Sections ◽  
Physical Structure ◽  
Energy Dispersive ◽  
Archaeological Sites ◽  
X Ray ◽  
Long Term Storage ◽  
Backscattered Electron ◽  
Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

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