scholarly journals INFLUENCE OF POROSITY OF PRESSED SAMPLES OF SUPERFINE ALUMINUM POWDER ON COMBUSTION PARAMETERS

2021 ◽  
pp. 199-205
Author(s):  
В.О. Попов ◽  
В.Н. Комов ◽  
Е.М. Попенко ◽  
А.В. Сергиенко
Keyword(s):  
Aluminum Powder ◽  
Gas Permeability ◽  
Side Surface ◽  
Combustion Mechanism ◽  
Refractory Materials ◽  
Second Stage ◽  
Nitride Formation ◽  
Ultrafine Aluminum ◽  
Ultrafine Aluminum Powder ◽  
Two Stages

Данная статья посвящена исследованию влияния пористости прессованных таблеток из сверхтонкого порошка алюминия (СТП Al). Определен механизм горения, протекающий в две стадии: первая, медленная, включающая в себя как «кольцевое» горение боковой поверхности, так и параллельное горение концентрическими слоями, вторая стадия объемная, сопровождающаяся резким самопроизвольным увеличением температуры горения и интенсивности свечения. Показано, что увеличение плотности упаковки СТП Al позволяет замедлить процесс окисления алюминия более чем в два раза. Это обусловлено снижением газопроницаемости таблетки и затруднением доступа воздуха вглубь образца. Повышение пористости материала позволяет регулировать процесс нитридообразования за счёт увеличения содержания азота в продуктах при фильтрационном механизме горения, что открывает возможности получения тугоплавких материалов. This article is devoted to the study of the effect of porosity of compressed tablets from ultrafine aluminum powder (STP Al). The combustion mechanism was determined, which proceeds in two stages: the first, slow, which includes both "ring" combustion of the side surface and parallel combustion with concentric layers, the second stage is volumetric, accompanied by a sharp spontaneous increase in the combustion temperature and glow intensity. It has been shown that an increase in the packing density of HFC Al makes it possible to slow down the process of aluminum oxidation by more than two times. This is due to a decrease in the gas permeability of the tablet and the difficulty of air access deep into the sample. An increase in the porosity of the material makes it possible to regulate the process of nitride formation by increasing the nitrogen content in the products during the filtration mechanism of combustion, which opens up the possibility of obtaining refractory materials.

Propellant grade ultrafine aluminum powder by RF induction plasma

2018 ◽  
Vol 29 (3) ◽  
pp. 804-812 ◽  
Author(s):  
P. Sai Karthik ◽  
S.B. Chandrasekhar ◽  
D. Chakravarty ◽  
P.V.V. Srinivas ◽  
V.S.K. Chakravadhanula ◽  
...  
Keyword(s):  
Aluminum Powder ◽  
Induction Plasma ◽  
Ultrafine Aluminum ◽  
Ultrafine Aluminum Powder ◽  
Rf Induction Plasma

Altered Fine Structure of B Lymphocytes Correlated with Defective Terminal Differentiation

1973 ◽  
Vol 31 ◽  
pp. 386-387
Author(s):  
Dale E. Bockman ◽  
L. Y. Frank Wu ◽  
Alexander R. Lawton ◽  
Max D. Cooper
Keyword(s):  
Immune Deficiency ◽  
B Lymphocytes ◽  
Plasma Cells ◽  
Present Report ◽  
Specific Antigen ◽  
Terminal Differentiation ◽  
Second Stage ◽  
Two Stages ◽  
Deficiency Diseases ◽  
Cell Line Generation

B-lymphocytes normally synthesize small amounts of immunoglobulin, some of which is incorporated into the cell membrane where it serves as receptor of antigen. These cells, on contact with specific antigen, proliferate and differentiate to plasma cells which synthesize and secrete large quantities of immunoglobulin. The two stages of differentiation of this cell line (generation of B-lymphocytes and antigen-driven maturation to plasma cells) are clearly separable during ontogeny and in some immune deficiency diseases. The present report describes morphologic aberrations of B-lymphocytes in two diseases in which second stage differentiation is defective.

Distributed Entropy Energy-Efficient Clustering algorithm for cluster head selection (DEEEC)

2020 ◽  
Vol 39 (6) ◽  
pp. 8139-8147
Author(s):  
Ranganathan Arun ◽  
Rangaswamy Balamurugan
Keyword(s):  
Energy Efficient ◽  
Clustering Algorithm ◽  
Cluster Head ◽  
Residual Energy ◽  
Energy Utilization ◽  
Sensor Nodes ◽  
Second Stage ◽  
Energy Efficient Clustering ◽  
Two Stages ◽  
Ch Selection

In Wireless Sensor Networks (WSN) the energy of Sensor nodes is not certainly sufficient. In order to optimize the endurance of WSN, it is essential to minimize the utilization of energy. Head of group or Cluster Head (CH) is an eminent method to develop the endurance of WSN that aggregates the WSN with higher energy. CH for intra-cluster and inter-cluster communication becomes dependent. For complete, in WSN, the Energy level of CH extends its life of cluster. While evolving cluster algorithms, the complicated job is to identify the energy utilization amount of heterogeneous WSNs. Based on Chaotic Firefly Algorithm CH (CFACH) selection, the formulated work is named “Novel Distributed Entropy Energy-Efficient Clustering Algorithm”, in short, DEEEC for HWSNs. The formulated DEEEC Algorithm, which is a CH, has two main stages. In the first stage, the identification of temporary CHs along with its entropy value is found using the correlative measure of residual and original energy. Along with this, in the clustering algorithm, the rotating epoch and its entropy value must be predicted automatically by its sensor nodes. In the second stage, if any member in the cluster having larger residual energy, shall modify the temporary CHs in the direction of the deciding set. The target of the nodes with large energy has the probability to be CHs which is determined by the above two stages meant for CH selection. The MATLAB is required to simulate the DEEEC Algorithm. The simulated results of the formulated DEEEC Algorithm produce good results with respect to the energy and increased lifetime when it is correlated with the current traditional clustering protocols being used in the Heterogeneous WSNs.

Analisis Kebutuhan Petunjuk Praktikum Berbasis Keterampilan Proses Sains untuk Mencapai Kemampuan Merancang Eksperimen

2019 ◽  
Vol 2 (2) ◽  
Author(s):  
Fitriah Khoirunnisa ◽  
Friska Septiani Silitonga ◽  
Veri Firmansyah
Keyword(s):  
Core Competence ◽  
Process Skills ◽  
Learning Materials ◽  
Science Process Skills ◽  
Second Stage ◽  
The Core ◽  
The Core Competence ◽  
Two Stages ◽  
Practical Instruction ◽  
Design Experiments

Penelitian ini bertujuan menganalisis kebutuhan petunjuk praktikum berbasis Keterampilan Proses Sains (KPS) untuk mencapai kemampuan merancang eksperimen pada materi kalor reaksi kalorimetri. Penelitian dilakukan terhadap peserta didik kelas XI SMA Negeri 2 Kota Tanjungpinang. Variabel penelitian mencakup analisis kebutuhan bahan ajar dan analisis kesesuaian Kompetensi Inti (KI) dan Kompetensi Dasar (KD). Jenis penelitian yang dilakukan adalah penelitian deskriptif kualitatif. Tahapan pertama dalam penelitian ini adalah menganalisis kebutuhan bahan ajar dengan cara membandingkan dua petunjuk praktikum yang selama ini telah digunakan di sekolah tersebut, ditinjau dari aspek struktur format penulisan, aspek kreativitas, dan aspek keterampilan proses sains yang terdapat dalam petunjuk praktikum. Sehingga didapatkan kesimpulan bahwa petunjuk praktikum yang selama ini digunakan tidak memberikan kesempatan kepada peserta didiknya untuk merancang eksperimen yang telah ditentukan. Tahapan kedua yaitu menganalisis kesesuaian kompetensi inti dan kompetensi dasar, yang bertujuan untuk menentukan indikator pencapaian kompetensi (IPK) yang akan menjadi acuan dalam mengembangkan petunjuk praktikum berbasis keterampilan proses sains. Dari kedua tahapan yang telah dilakukan maka dapat disimpulkan bahwa peserta didik memerlukan petunjuk praktikum yang mampu mengonstruksi pikiran dan mengaktifkan kinerja mereka, sehingga pendekatan Keterampilan Proses Sains menjadi pilihan dalam mengembangkan petunjuk praktikum yang sesuai dengan karakteristik kurikulum 2013.   This research aims to analyze the needs of Science Process Skills based Practical Instruction to achieve the ability to design experiments on the calor of reaction. This research was done to the students of class XI SMA Negeri 2 Tanjungpinang City. Research Variable includes the analysis of the needs of the learning materials and analysis of the suitability of the Core Competence (KI) and Basic Competence (KD). The type of research conducted is descriptive qualitative research. The first stages in this research is to analyze the needs of learning materials by comparing two practical instructions that had been implementing in the school, from the aspects of the structure of writing format, creativity, and science process skills embedded in practical instructions. The conclusion of this research that current practical instructions does not give an opportunity to the participants to design determined experiments. The second stage, namely analyzing the suitability of core competence and basic competence, which aims to determine the indicators of achievement of the competencies (GPA) which will be a reference in developing process skills-based teaching instructions science. Of the two stages that has been done then it can be concluded that learners need practical instructions to construct  thinking and and their performance, so the Science Process Skills approach is an option in developing practical instruction suitable for the characteristics of the curriculum of 2013.

ESTIMATING GAS AND ROCK OUTBURST RISK ON THE BASIS OF KNOWLEDGE AND EXPERIENCE – THE EXPERT SYSTEM BASED ON FUZZY LOGIC

2014 ◽  
Vol 59 (1) ◽  
pp. 41-52 ◽  
Author(s):  
Norbert Skoczylas
Keyword(s):  
Fuzzy Logic ◽  
Expert System ◽  
Mining Industry ◽  
Automatic Assessment ◽  
Science Field ◽  
Second Stage ◽  
Two Stages ◽  
Outburst Hazard

Abstract The Author endeavored to consult some of the Polish experts who deal with assessing and preventing outburst hazards as to their knowledge and experience. On the basis of this knowledge, an expert system, based on fuzzy logic, was created. The system allows automatic assessment of outburst hazard. The work was completed in two stages. The first stage involved researching relevant sources and rules concerning outburst hazard, and, subsequently, determining a number of parameters measured or observed in the mining industry that are potentially connected with the outburst phenomenon and can be useful when estimating outburst hazard. Then, the Author contacted selected experts who are actively involved in preventing outburst hazard, both in the industry and science field. The experts were anonymously surveyed, which made it possible to select the parameters which are the most essential in assessing outburst hazard. The second stage involved gaining knowledge from the experts by means of a questionnaire-interview. Subjective opinions on estimating outburst hazard on the basis of the parameters selected during the first stage were then systematized using the structures typical of the expert system based on fuzzy logic.

Integrated assessment and mapping of the environmental situation in the Russian Federation regions

2017 ◽  
Vol 924 (6) ◽  
pp. 6-16
Author(s):  
V.S. Tikunov ◽  
O.Yu. Chereshnia
Keyword(s):  
Russian Federation ◽  
Pollution Index ◽  
Pollution Level ◽  
Anthropogenic Pressure ◽  
Environmental Capacity ◽  
Environmental Friendliness ◽  
Second Stage ◽  
Environmental Situation ◽  
The Russian Federation ◽  
Two Stages

The article presents a methodology for a comprehensive assessment of the environmental situation in Russian Federation regions based on the pollution index and the index of the ecological tension. The evaluation was carried out in two stages. At the first stage, the degree of pollution of the atmosphere, hydrosphere and lithosphere of the regions was estimated on the basis of the emission of pollutants into the atmosphere, departing from stationary sources, the formation of solid domestic wastes (SDW) and the discharge of contaminated wastewater. Based on these three indicators, a pollution index was constructed that estimates aggregate pollution level. In the second stage, the authors made the estimation of loads generated by atmospheric emissions, solid waste and waste water discharged into the territory of each region, per capita and in relation to the environmental capacity of the economy. This allows us to take into account the area of pollution, anthropogenic pressure and environmental responsibility of the population, as well as the environmental friendliness of production. On the basis of relative indicators, the index of ecological tension was created.

scholarly journals The Psychology behind Knowledge Hiding in an Organization

2021 ◽  
Vol 11 (2) ◽  
pp. 57
Author(s):  
Roksana Binte Rezwan ◽  
Yoshi Takahashi
Keyword(s):  
Knowledge Management ◽  
Literature Review ◽  
Systematic Literature Review ◽  
Personal Goals ◽  
Psychological Process ◽  
Personal Goal ◽  
Second Stage ◽  
Management Literature ◽  
Two Stages ◽  
Knowledge Hiding

This study aimed to understand the psychological process behind employees’ knowledge hiding (KH) behaviors in organizations. KH is an intentional act of concealing knowledge when it is requested by a colleague and can lead to counterproductive consequences for the organization. Therefore, this study synthesized previous studies (n = 88) on KH through a systematic literature review. We used the cognitive–motivational–relational (CMR) theory of emotion to create a framework for the studies’ findings. Based on the framework, the psychological process behind KH has two stages—personal goal generation and the knowledge-request event appraisal process, each of which contains its own CMR process. In the first stage, an individual’s internal and external attributes related to the organization shape their personal goals. In the second stage, an individual appraises the features of a knowledge-request event in terms of both their personal goal and the internal and external attributes that created the goal. If the knowledge request is appraised as harmful for the personal goal, emotion arises and leads to the manifestation of KH. This study contributes to the knowledge management literature as, to our knowledge, it is the first to propose a CMR theory-based framework to understand the overall psychological process behind KH.

Perceiving at a distance: enaction, exteriority and possibility – a tribute to John Stewart

2021 ◽  
pp. 105971232110310
Author(s):  
Charles Lenay
Keyword(s):  
Experimental Study ◽  
Perceptual Experience ◽  
Spatial Perception ◽  
Distant Object ◽  
New Approach ◽  
Second Stage ◽  
The Moment ◽  
Two Stages

The aim of this article is to offer a new approach of perception regarding the position of a distant object. It is also a tribute to John Stewart who accompanied the first stages of this research. Having already examined the difficulties surrounding questions of the perception of exteriority within the framework of enactive approaches, we will proceed in two stages. The first stage will consist of an attempt to explain distal perception in terms of individual sensorimotor invariants. This poses the problem but fails to solve it. The second stage will propose a new pathway to account for spatial perception; a pathway that does not deny the initial intuitions of the autopoietic enactive approaches, but one which radically changes the conception of cognition by considering, from the perceptual stage, the need to take into account interindividual interactions. The protocol of an original experimental study will characterize this new approach considering the perceptual experience of objects at a distance, in exteriority, in a space of possibilities without parting from the domain of interaction. To do this, we have to work at the limits of the perceptual crossing, that is, at the moment when the perceptual reciprocity between different subjects begins to disappear.

Virtual fit evaluation of pants using the Adaptive Network Fuzzy Inference System

2021 ◽  
pp. 004051752110205
Author(s):  
Xueqing Zhao ◽  
Ke Fan ◽  
Xin Shi ◽  
Kaixuan Liu
Keyword(s):  
Fuzzy Inference System ◽  
Fuzzy Inference ◽  
Test Accuracy ◽  
Adaptive Network ◽  
Data Set ◽  
Inference System ◽  
Second Stage ◽  
Simulated Environment ◽  
Two Stages ◽  
Fold Cross Validation

Virtual reality is a technology that allows users to completely interact with a computer-simulated environment, and put on new clothes to check the effect without taking off their clothes. In this paper, a virtual fit evaluation of pants using the Adaptive Network Fuzzy Inference System (ANFIS), VFE-ANFIS for short, is proposed. There are two stages of the VFE-ANFIS: training and evaluation. In the first stage, we trained some key pressure parameters by using the VFE-ANFIS; these key pressure parameters were collected from real try-on and virtual try-on of pants by users. In the second stage, we evaluated the fit by using the trained VFE-ANFIS, in which some key pressure parameters of pants from a new user were determined and we output the evaluation results, fit or unfit. In addition, considering the small number of input samples, we used the 10-fold cross-validation method to divide the data set into a training set and a testing set; the test accuracy of the VFE-ANFIS was 94.69% ± 2.4%, and the experimental results show that our proposed VFE-ANFIS could be applied to the virtual fit evaluation of pants.

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