scholarly journals Efficiency increase in combined electro-chemical grinding of hard alloys by diamond metal bonded disks

2017 ◽  
Vol 2 (2) ◽  
pp. 3-8
Author(s):  
Ольга Медведева ◽  
Olga Medvedeva ◽  
Александр Янюшкин ◽  
Aleksandr Yanyushkin ◽  
Павел Архипов ◽  
...  
Keyword(s):  
Theoretical Models ◽  
Capacity Factor ◽  
Hard Alloys ◽  
Metal Bond ◽  
Disc Cutting ◽  
Efficiency Increase ◽  
The Stability ◽  
Cutting Capacity ◽  
Diamond Disc

In the paper there are emphasized problems connected with the use of diamond metal bond abrasive discs at the processing of hard alloys. The reasons of cutting capacity decrease are pointed out which limit a wide-spread use of a diamond metal bond tool. It is established that for the achievement of a required productivity and quality of ready products is possible at the expense of the application of electro-chemical and electro-physical methods of stropping and also due to the improvement of abrasive disc designs. This work reports the investigations of a cutting capacity of diamond discs at the working of hard alloys by a combined method of electro-chemical grinding with simultaneous continuous stropping. As an output parameter there was accepted a cutting capacity factor of a diamond which was assesses according to the changes in effective working capacity. On the basis of the results of the experimental data processed there were obtained theoretical models of the dependence of the cutting capacity factor upon electric and mechanical constituents of the modes of combined electro-chemical grinding. A complex of investigations directed to the detection of efficient modes ensuring the stability of cutting capacity in diamond metal bond discs is carried out. It is experimentally confirmed that the application of the method of combined electro-chemical grinding with the simultaneous continuous disc stropping at working hard alloy materials allows increasing diamond disc cutting capacity by 15% in comparison with other methods of the diamond working of such materials.

Criteria for evaluation of the coordinate measurements quality of parts geometric parameters at pilot-experimental production

2019 ◽  
pp. 3-8
Author(s):  
N.Yu. Bobrovskaya ◽  
M.F. Danilov
Keyword(s):  
Quality Indicators ◽  
Quality Management System ◽  
Technical Specification ◽  
Experimental Production ◽  
Technological Heredity ◽  
Coordinate Measurements ◽  
Reasonable Choice ◽  
The Stability ◽  
Geometric Elements

The criteria of the coordinate measurements quality at pilot-experimental production based on contemporary methods of quality management system and traditional methods of the measurements quality in Metrology are considered. As an additional criterion for quality of measurements, their duration is proposed. Analyzing the problem of assessing the quality of measurements, the authors pay particular attention to the role of technological heredity in the analysis of the sources of uncertainty of coordinate measurements, including not only the process of manufacturing the part, but all stages of the development of design and technological documentation. Along with such criteria as the degree of confidence in the results of measurements; the accuracy, convergence, reproducibility and speed of the results must take into account the correctness of technical specification, and such characteristics of the shape of the geometric elements to be controlled, such as flatness, roundness, cylindrical. It is noted that one of the main methods to reduce the uncertainty of coordinate measurements is to reduce the uncertainty in the initial data and measurement conditions, as well as to increase the stability of the tasks due to the reasonable choice of the basic geometric elements (measuring bases) of the part. A prerequisite for obtaining reliable quality indicators is a quantitative assessment of the conditions and organization of the measurement process. To plan and normalize the time of measurements, the authors propose to use analytical formulas, on the basis of which it is possible to perform quantitative analysis and optimization of quality indicators, including the speed of measurements.

Statistical Management of Food Production Processes

2020 ◽  
pp. 30-35
Author(s):  
N.A. Jurk ◽  
Keyword(s):  
Production Process ◽  
Control Chart ◽  
Food Production ◽  
Time Interval ◽  
Bakery Products ◽  
Shewhart Control ◽  
Manufactured Products ◽  
Mnemonic Technique ◽  
The Stability

The article presents scientific research in the field of statistical controllability of the food production process using the example of bakery products for a certain time interval using statistical methods of quality management. During quality control of finished products, defects in bakery products were identified, while the initial data were recorded in the developed form of a checklist for registering defects. It has been established that the most common defect is packaging leakage. For the subsequent statistical assessment of the stability of the production process and further analysis of the causes of the identified defect, a Shewhart control chart (p-card by an alternative feature) was used, which allows you to control the quality of manufactured products by the number of defects detected. Analyzing the control chart, it was concluded that studied process is conditionally stable, and the emerging defects are random. At the last stage of the research, the Ishikawa causal diagram was used, developed using the 6M mnemonic technique, in order to identify the most significant causes that affect the occurrence of the considered defect in bakery products. A more detailed study will allow the enterprise to produce food products that meet the established requirements.

Cancer and Cancer Treatment-Related Cognitive Impairment

2019 ◽  
pp. 60-83
Author(s):  
James C.  Root ◽  
Elizabeth Ryan ◽  
Tim A. Ahles
Keyword(s):  
Cancer Survivors ◽  
Cancer Treatment ◽  
Clinical Presentation ◽  
Functional Neuroimaging ◽  
Theoretical Models ◽  
Future Research ◽  
Cognitive Changes ◽  
Central Nervous System Cancer ◽  
Pharmacologic Treatments

As the population of cancer survivors has grown into the millions, there is increasing emphasis on understanding how late effects of treatment impact survivors’ ability return to work/school, ability to function and live independently, and overall quality of life. Cognitive changes are one of the most feared problems among cancer survivors. This chapter describes the growing literature examining cognitive changes associated with non-central nervous system cancer and cancer treatment. Typical elements of cancer treatment are discussed, followed by a description of clinical presentation, self-reported and objectively assessed cognitive findings, and results of structural and functional neuroimaging research. Genetic and other risk factors for cognitive decline following treatment are identified and discussed, together with biomarkers and animal models of treatment-related effects. This is followed by a discussion of behavioral and pharmacologic treatments. Finally, challenges and recommendations for future research are provided to help guide subsequent research and theoretical models.

scholarly journals Identifying Stabilising Effects on Survey Based Life Satisfaction Using Quasi-maximum Likelihood Estimation

2021 ◽  
Author(s):  
Johannes Klement
Keyword(s):  
Life Satisfaction ◽  
Maximum Likelihood ◽  
Maximum Likelihood Estimation ◽  
Negative Binomial ◽  
Measurement Instrument ◽  
Likelihood Estimation ◽  
Satisfaction Scale ◽  
Quasi Maximum Likelihood ◽  
The Stability

AbstractTo which extent do happiness correlates contribute to the stability of life satisfaction? Which method is appropriate to provide a conclusive answer to this question? Based on life satisfaction data of the German SOEP, we show that by Negative Binomial quasi-maximum likelihood estimation statements can be made as to how far correlates of happiness contribute to the stabilisation of life satisfaction. The results show that happiness correlates which are generally associated with a positive change in life satisfaction, also stabilise life satisfaction and destabilise dissatisfaction with life. In such as they lower the probability of leaving positive states of life satisfaction and increase the probability of leaving dissatisfied states. This in particular applies to regular exercise, volunteering and living in a marriage. We further conclude that both patterns in response behaviour and the quality of the measurement instrument, the life satisfaction scale, have a significant effect on the variation and stability of reported life satisfaction.

scholarly journals Quantifying the Effects of Vibration on Medicines in Transit Caused by Fixed-Wing and Multi-Copter Drones

Drones ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 22
Author(s):  
Andrew Oakey ◽  
Tim Waters ◽  
Wanqing Zhu ◽  
Paul G. Royall ◽  
Tom Cherrett ◽  
...  
Keyword(s):  
Road Transport ◽  
Uv Spectra ◽  
Frequency Spectra ◽  
Vibration Measurements ◽  
British Pharmacopoeia ◽  
Medical Products ◽  
Industry Standard ◽  
The Stability ◽  
In Transit

The concept of transporting medical products by drone is gaining a lot of interest amongst the medical and logistics communities. Such innovation has generated several questions, a key one being the potential effects of flight on the stability of medical products. The aims of this study were to quantify the vibration present within drone flight, study its effect on the quality of the medical insulin through live flight trials, and compare the effects of vibration from drone flight with traditional road transport. Three trials took place in which insulin ampoules and mock blood stocks were transported to site and flown using industry standard packaging by a fixed-wing or a multi-copter drone. Triaxial vibration measurements were acquired, both in-flight and during road transit, from which overall levels and frequency spectra were derived. British Pharmacopeia quality tests were undertaken in which the UV spectra of the flown insulin samples were compared to controls of known turbidity. In-flight vibration levels in both the drone types exceeded road induced levels by up to a factor of three, and predominant vibration occurred at significantly higher frequencies. Flown samples gave clear insulin solutions that met the British Pharmacopoeia specification, and no aggregation of insulin was detected.

scholarly journals Optical Analysis of RF Sputtering Plasma through Colour Characterization

Coatings ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 315 ◽  
Author(s):  
Ali Salimian ◽  
Roohollah Haghpanahan ◽  
Abul Hasnath ◽  
Hari Upadhyaya
Keyword(s):  
Rf Sputtering ◽  
Plasma Source ◽  
Film Coating ◽  
Chamber Pressure ◽  
Plasma Power ◽  
Plasma Sputtering ◽  
Chromaticity Index ◽  
Colour Parameters ◽  
The Stability

The photometric properties of an radio frequency (RF)-based sputtering plasma source were monitored through optical spectroscopy. The colour of the plasma source was deduced based on conventional chromaticity index analysis and it was compared to the direct spectral data plots of the emission peaks to investigate the possibility of characterising the plasma based on its specific colour and exploring the potential of defining a new method by which the plasma sputtering process can be addressed based on the plasma colour parameters. The intention of this investigation is to evaluate the possibility of simplifying the monitoring and assessment of the sputtering process for applied scientists operating plasma sputter deposition systems. We demonstrate a viable potential for this technique in terms of providing information regarding the stability of the plasma, chamber pressure, and plasma power; however, further work is underway to verify and assess a relationship between the quality of the thin film coating and the colour characteristics of the deposition plasma. Here, we only focus on the feasibility of such an approach and demonstrate interesting observations. We observed a linear relationship between the colour functions and the plasma power, while the stability of the sputtering plasma can be assessed based on the plasma colour functions. The colour functions also follow a unique pattern when the working gas pressure is increased.

scholarly journals High temperature structural study of decagonal Al-Cu-Rh quasicrystal.

2014 ◽  
Vol 70 (a1) ◽  
pp. C94-C94
Author(s):  
Pawel Kuczera ◽  
Walter Steurer
Keyword(s):  
Structural Changes ◽  
Configurational Entropy ◽  
Lattice Vibrations ◽  
X Ray Diffraction ◽  
Stabilization Mechanism ◽  
X Ray ◽  
Comparative Structure ◽  
The Stability

The structure of d(ecagonal)-Al-Cu-Rh has been studied as a function of temperature by in-situ single-crystal X-ray diffraction in order to contribute to the discussion on energy or entropy stabilization of quasicrystals (QC) [1]. The experiments were performed at 293 K, 1223 K, 1153 K, 1083 K, and 1013 K. A common subset of 1460 unique reflections was used for the comparative structure refinements at each temperature. The results obtained for the HT structure refinements of d-Al-Cu-Rh QC seem to contradict a pure phasonic-entropy-based stabilization mechanism [2] for this QC. The trends observed for the ln func(I(T1 )/I(T2 )) vs.|k⊥ |^2 plots indicate that the best on-average quasiperiodic order exists between 1083 K and 1153 K, however, what that actually means is unclear. It could indicate towards a small phasonic contribution to entropy, but such contribution is not seen in the structure refinements. A rough estimation of the hypothetic phason instability temperature shows that it would be kinetically inaccessible and thus the phase transition to a 12 Å low T structure (at ~800 K) is most likely not phason-driven. Except for the obvious increase in the amplitude of the thermal motion, no other significant structural changes, in particular no sources of additional phason-related configurational entropy, were found. All structures are refined to very similar R-values, which proves that the quality of the refinement at each temperature is the same. This suggests, that concerning the stability factors, some QCs could be similar to other HT complex intermetallic phases. The experimental results clearly show that at least the ~4 Å structure of d-Al-Cu-Rh is a HT phase therefore entropy plays an important role in its stabilisation mechanism lowering the free energy. However, the main source of this entropy is probably not related to phason flips, but rather to lattice vibrations, occupational disorder unrelated to phason flips like split positions along the periodic axis.

St Symeon the New Theologian (969-1022): Byzantine spiritual renewal in search of a precedent

1997 ◽  
Vol 33 ◽  
pp. 75-90
Author(s):  
John Anthony McGuckin
Keyword(s):  
Christian Tradition ◽  
Spiritual Renewal ◽  
Divine Love ◽  
The West ◽  
Conference Theme ◽  
Autobiographical Accounts ◽  
The Stability ◽  
The Church

St Symeon the New Theologian is, without question, one of the most original and intriguing writers of medieval Byzantium. Indeed, although still largely unknown in the West, he is surely one of the greatest of all Christian mystical writers; not only for the remarkable autobiographical accounts he gives of several visions of the divine light, but also for the passionate quality of his exquisite Hymns of Divine Love, the remarkable intensity of his pneumatological doctrine, and the corresponding fire he brings to his preaching of reform in the internal and external life of the Church. He was a highly controversial figure in his own day. His disciples venerated him as a saint who had returned to the roots of the Christian tradition and personified its repristinization. His opponents, who secured his deposition and exile, regarded him as a dangerously unbalanced incompetent who, by overstressing the value of personal religious fervour, had endangered the stability of that tradition. The Vita which we possess was composed in 1054, in an attempt to rehabilitate Symeon’s memory and prepare for the return of his relics to the capital from which he had been expelled when alive. This paper will investigate how he himself understood and appropriated aspects of the earlier tradition (particularly monastic spirituality), hoping to elucidate why he felt himself inspired to reformist zeal, and why many of his contemporaries (not simply his ‘worldly opponents’ as his hagiographer would have us believe) regarded him as unbalanced. It will end by attempting some reflection on what the controversy reveals on the larger front about how the Church ‘selectively looks back on itself, so to paraphrase our president’s description of the conference theme, and whether the model of tradition and its reception exemplified in this Byzantine writer can offer anything to the dialogue between history and theology which the doctrine of Tradition (Paradosis) inevitably initiates.

Design of Hydraulic Descaling Computer Control System

2014 ◽  
Vol 608-609 ◽  
pp. 19-22
Author(s):  
Ping Xu ◽  
Jian Gang Yi
Keyword(s):  
Control System ◽  
Stability Problem ◽  
Computer Control ◽  
Control Methods ◽  
Computer Control System ◽  
Control Software ◽  
Pressure Water ◽  
Working Principle ◽  
The Stability

Hydraulic descaling system is the key device to ensure the surface quality of billet. However, traditional control methods lead to the stability problem in hydraulic descaling system. To solve the problem, the construction of the hydraulic descaling computer control system is studied, the working principle of the system is analyzed, and the high pressure water bench of hydraulic descaling is designed. Based on it, the corresponding computer control software is developed. The application shows that the designed system is stable in practice, which is helpful for enterprise production.

Sign in / Sign up

Export Citation Format

Share Document