scholarly journals Caracterización dimensional con ultrasonido por arreglo de fases de discontinuidades inducidas en acero ASTM A36 mediante procesos de electroerosión y soldadura SMAW

2021 ◽  
Vol 20 (3) ◽  
Author(s):  
Carlos Andrés Galán-Pinilla ◽  
Luz Amparo Quintero-Ortiz ◽  
Julián Orlando Herrera-Ortiz
Keyword(s):  
Ultrasonic Testing ◽  
Phased Array ◽  
Ultrasonic Beam ◽  
Butt Weld ◽  
Second Stage ◽  
A36 Steel ◽  
Ultrasound Inspection ◽  
Two Stages ◽  
Geometric Morphology ◽  
Phase Arrangement

This research evaluates the effect of the variables of Phased Array Ultrasonic Testing(PAUT) on the sectoral angular beam scans “S-Scan” and the geometric morphology of planar discontinuities such as the inclination forthe ultrasonic beam and the shape of the extremity on accuracy in measurements. The study was carried out in two stages. Duringthe first stage, eight ASTM A36 steel samples with machined notches by penetration from EDM and a welded sample with lack of penetration in a butt weld were designed and produced. In the second stage, it wasmeasured the size of the discontinuities using ultrasound inspection and different configurations of the phase arrangement. The effect of each variable and inspection setting with errors between 0.2 % and 120 % were determined by statistical analysis.

Image Analysis of Indications in Fillet Welding by Phased Array Ultrasonic Technique

2017 ◽  
Author(s):  
Youwei Zhang ◽  
Yuqing Yang ◽  
Qingfeng Li ◽  
Le Chen
Keyword(s):  
Ultrasonic Testing ◽  
Phased Array ◽  
Surface Defects ◽  
Great Influence ◽  
Focal Depth ◽  
Slag Inclusion ◽  
Butt Weld ◽  
Near Surface ◽  
Butt Welding ◽  
Fillet Welding

The steel frame for carrying boiler in power generation station is usually connected by fillet welding like corner or tee joints. Traditionally, we inspect this type of welding by Magnetic Particle Testing (MT) and Dye Penetration Testing (PT), by which only the surface or near surface defects can be detected, and the internal defects in butt welding is inspected by Ultrasonic Testing (UT) and Radiographic Testing (RT). Though ultrasonic Testing (UT) has various advantage in flat butt weld, it requires a better condition on the detection surface avoiding the interference of being rough, irregular in shape, very small or thin, or not homogeneous. Due to the geometric shape or structural constrains in fillet welding, volumetric defects are sometimes unable to be detected by RT. Currently, there are no effective methods of Non-destructive examination (NDE) for the volumetric flaws in this type of welding which connects the steel column and reinforcing plate. Normally, the volumetric and plannar defects of fillet welding are commonly as: incomplete penetration, slag inclusion, porosity, lack of fusion and cracks, which have a great influence on the welding quality. This paper aims at using the advantages of Phased Array Ultrasonic Testing (PAUT) to detect the fillet weld: • Focal depth is variable. • Scanning range is large, steering beam from −89° to 89°. • Covering large volume at single position of probe. By setting different types of artificial flaws, we carried out the reliability analysis of this kind of welding with PAUT. Through observing the representative images of flaws, we can directly know the location of defects in the weld. According to the data provided by the scan software, we can read its depth and distance from the weld center line, which helps us to locate defects in weld precisely.

An Ultrasonic Phased Array Evaluation of Cast Austenitic Stainless Steel Pressurizer Surge Line Piping Welds

2010 ◽  
Author(s):  
Aaron A. Diaz ◽  
Anthony D. Cinson ◽  
Susan L. Crawford ◽  
Traci L. Moran ◽  
Michael T. Anderson
Keyword(s):  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Ultrasonic Testing ◽  
Phased Array ◽  
Fatigue Cracks ◽  
Ultrasonic Beam ◽  
Custom Made ◽  
Ultrasonic Phased Array ◽  
Surge Line ◽  
Thermal Fatigue Cracks

A set of circumferentially oriented thermal fatigue cracks (TFCs) were implanted into three cast austenitic stainless steel (CASS) pressurizer (PZR) surge-line specimens (pipe-to-elbow welds) that were fabricated using vintage CASS materials formed in the 1970s, and flaw responses from these cracks were used to evaluate detection and sizing performance of the phased-array (PA) ultrasonic testing (UT) methods applied. Four different custom-made PA probes were employed in this study, operating nominally at 800 kHz, 1.0 MHz, 1.5 MHz, and 2.0 MHz center frequencies. The CASS PZR surge-line specimens were polished and chemically etched to bring out the microstructures of both pipe and elbow segments. Additional studies were conducted and documented to address baseline CASS material noise and observe possible ultrasonic beam redirection phenomena.

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.

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