scholarly journals Bulkhead Door – Critical Evacuation States

2017 ◽  
Vol 24 (1) ◽  
pp. 66-71 ◽  
Author(s):  
Józef Flizikowski ◽  
Weronika Kruszelnicka ◽  
Mirosław Michałowski ◽  
Grzegorz Szala ◽  
Andrzej Tomporowski
Keyword(s):  
Present Article ◽  
Hydraulic System ◽  
Hydraulic Fluid ◽  
Critical States ◽  
High Level

Abstract The article is a preliminary to a modification concept of the sliding watertight bulkhead door used on ships and vessels. Hydraulic or electro-hydraulic drives used to move these doors require complicated and extended pressure installations with large amounts of hydraulic fluid. Well-known operational drawbacks of these installations include high level of noise and possibility of various leaks in the hydraulic system. Being the first in a series, the present article describes and analyses critical states which can take place during evacuation of people through openings in the watertight bulkhead doors on seagoing ships and vessels.

Quality Control of eLearning Research Design

2018 ◽  
Vol 9 (3) ◽  
pp. 46-67
Author(s):  
Hamdy Ahmed Abdelaziz
Keyword(s):  
Quality Control ◽  
Blended Learning ◽  
Present Article ◽  
Research Design ◽  
Research Methodology ◽  
Field Research ◽  
New Method ◽  
Arab States ◽  
High Level ◽  
Design And Production

The present article aimed at developing a research methodology to ensure quality control of eLearning field research design and production. The idea of the present research was to investigate effective and ineffective practices in eLearning field. The analysis of a sample of researches and studies (n = 200), conducted in the field of eLearning and Blended Learning in the Arab states revealed that the vast majority of eLearning researches and studies (70%) were stereotypical. Therefore, the researcher developed a list of indicators that ensure quality control of eLearning researches design. A new methodology to design and produce eLearning research is proposed. The proposed methodology contains four stages: Identify Investigate, Prototype, and Produce. Implementation of these stages required the adoption of a tetrad dialogue during the course of answering the six patterns of question: what, who, when, where, how, and why. In addition, the adoption of this new method may support producing adaptive and innovative eLearning research with high level of quality.

Ensuring the Reliability of an Aircraft Engine Hydraulic System

2014 ◽  
Vol 616 ◽  
pp. 126-134 ◽  
Author(s):  
Janka Mihalčová ◽  
Peter Šmeringai
Keyword(s):  
Hydraulic System ◽  
Kinematic Viscosity ◽  
Chemical Properties ◽  
Aircraft Engine ◽  
Hydraulic Fluid ◽  
Aircraft Engines ◽  
Ftir Analysis ◽  
Physical Chemical ◽  
Hydraulic Fluids ◽  
Degradation Degree

The article deals with the issue of ensuring the reliability of aircraft engines operation via hydraulic fluids properties monitoring. There are presented the results of the hydraulic fluid Aero Shell Fluid 41 (ASF 41) properties evaluation in the hydraulic system of a double-flow turbosupercharged aircraft engine AI-25TL. In the hydraulic fluid, there were observed the quantity and distribution of mechanical particles according to their size in accordance with the ISO Cleanliness Code, ISO 4406.There was also determined kinematic viscosity according to the standard EN ISO 3104+AC. FTIR analysis of the infrared spectrum was used to determine the degradation degree of the hydraulic fluid physical-chemical properties.

scholarly journals Research of Biodegradable Fluid Impacts on Operation of Tractor Hydraulic System

2017 ◽  
Vol 20 (2) ◽  
pp. 42-45 ◽  
Author(s):  
Zdenko Tkáč ◽  
Štefan Čorňák ◽  
Vladimír Cviklovič ◽  
Ján Kosiba ◽  
Josef Glos ◽  
...  
Keyword(s):  
Hydraulic System ◽  
Acid Number ◽  
Hydraulic Fluid ◽  
Spectroscopy Analysis ◽  
Total Acid ◽  
Transmission Systems ◽  
Transmission Oil ◽  
Total Acid Number ◽  
Transmission Fluid ◽  
Agricultural Tractors

Abstract This paper is focused on the impacts of the biodegradable hydraulic and transmission fluid (Universal Tractor Transmission Oil) on operation of tractor hydraulic and transmission systems. The fluid was used in the hydraulic and transmission systems of a Zetor Proxima 6321 tractor. Fluid samples were taken from the Zetor Proxima 6321 tractor at intervals of 250 engine hours. These samples were subjected to an infrared spectroscopy analysis in order to measure the total acid number and perform the ferrography analysis. This paper proves minimal impacts of the biodegradable hydraulic fluid on operation of the Zetor Proxima 6321 tractor. The biodegradable fluid meets the requirements for the operation of agricultural tractors in terms of low impacts on the wear of hydraulic components.

Study of Hydraulic System Component Storage with a Rust Inhibited Barium Free Development Hydraulic Fluid Candidate

2006 ◽  
Author(s):  
Lois J. Gschwender ◽  
Angie Campo ◽  
Carl E. Snyder ◽  
Shashi K. Sharma ◽  
Tim Jenney ◽  
...  
Keyword(s):  
Hydraulic System ◽  
System Component ◽  
Hydraulic Fluid ◽  
Free Development

scholarly journals Eye-movement recording as a tool for studying syntactic processing in a second language: a review of methodologies and experimental findings

2005 ◽  
Vol 21 (2) ◽  
pp. 175-198 ◽  
Author(s):  
Cheryl Frenck-Mestre
Keyword(s):  
Second Language ◽  
Present Article ◽  
Eye Movement ◽  
Syntactic Processing ◽  
Reading Process ◽  
Language Studies ◽  
Invaluable Tool ◽  
Experimental Findings ◽  
High Level ◽  
Future Work

The complex trace of saccades, fixations and regressions that the eyes make while taking in a line of text is unquestionably one of the richest accounts available as concerns the process of reading. Recording these jumps, stops and re-takes provides a to-the-letter, millisecond-precise report of the readers’ immediate syntactic processing as well as revisions thereof. In addition, the influence of innumerable factors -from low-level visual conditions to high-level pragmatic cues - on the reading process can be measured via this method, thereby rendering possible the testing of various psycholinguistic models of parsing and comprehension. For all of these reasons, eye-movement recording has become an invaluable tool in the study of how readers process text. Interestingly, however, only a handful of eye-movement studies have been published as concerns reading in the second language. The goal of the present article is to outline the findings of these second language studies and, hopefully, to encourage future work in the field using this tool.

Hydraulic Fluid Mathematical Modeling

2013 ◽  
Vol 432 ◽  
pp. 127-132
Author(s):  
Pei Cheng Shi ◽  
Yang Min Sun
Keyword(s):  
Hydraulic System ◽  
Fluid Pressure ◽  
Mathematical Expression ◽  
Effective Density ◽  
Hydraulic Fluid ◽  
Factors Affecting ◽  
Air Content ◽  
Linear Behavior ◽  
Study Results ◽  
Non Linear

In hydraulic system, the property of hydraulic fluid will have non-linear behavior change when the temperature and pressure of fluid and the amount of dissolved and undissolved air vary, thus influencing the hydraulic system performance. The authors first studied the property of hydraulic fluid, and then constructed the mathematical expression theoretically, which shows the hydraulic fluid effective density using the fluid pressure, temperature and air content parameters. The computation simulations of the hydraulic fluid non-linear property were carried out using the simulation program based on MATLAB software. Meanwhile the key-factors affecting the hydraulic effective density and fluid bulk modulus were discussed. The study results provide computing foundation for designing quickly responsive, running steady and highly accurate hydraulic transmission system, which have important theory and engineering significance.

scholarly journals Laboratory tests of the hydraulic pump operating load with monitoring of changes in the physical properties

2021 ◽  
Vol 54 (3-4) ◽  
pp. 243-251
Author(s):  
Lubomir Hujo ◽  
Jozef Nosian ◽  
Marcin Zastempowski ◽  
Jan Kosiba ◽  
Jerzy Kaszkowiak ◽  
...  
Keyword(s):  
Physical Properties ◽  
Present Article ◽  
Water Concentration ◽  
Hydraulic Fluid ◽  
Efficiency Change ◽  
Hydraulic Pump ◽  
Laboratory Conditions ◽  
A Value ◽  
Operating Load ◽  
Agricultural Tractors

The present article deals with the physical properties monitoring of the transmission-hydraulic fluid, and changes of those properties due the operating load of the hydraulic pump in laboratory conditions. Tests of the transmission-hydraulic fluid were performed in laboratory conditions with the simulation of the operating load, so as to simulate the real conditions under which hydraulic circuit of the agricultural tractors operates. The universal transmission-hydraulic fluid was subjected to analysis, where the samples of the fluid were taken sequentially according to the chosen methodology at intervals of 250 and 500 h. The results of the present article include the evaluation of the physical properties of the fluid and the flow efficiency change of the hydraulic pump after 250 and 500 h of operation, while simulating the operation load. Based on a laboratory test, we found that after working for 500 h, the dynamic viscosity of the examined hydraulic fluid at 40°C decreased by 2.92 mPa.s and at 100°C decreased by 0.64 mPa.s. When determining the kinematic viscosity of the hydraulic fluid after working for 500 h, we recorded its decrease, namely, at a temperature of 40°C by a value of 3.37 mm2/s and at a temperature of 100°C, its value decreased by 0.77 mm2/s. In the analysis of the test oil samples, we found that the level of water contamination of the hydraulic fluid decreases with increasing number of hours worked. Specifically, the water concentration in the hydraulic fluid decreased by 0.031%. At the same time, we recorded a slight decrease in the flow efficiency of the hydraulic pump, specifically by a value of 0.03% after 500 h worked. After working 500 h, we found that the range of abrasion particles in the transmission-hydraulic fluid is within the prescribed range, which is determined by the standard D6595-00.

Performance in Planning: Processes, Requirements, and Errors

2001 ◽  
Vol 5 (3) ◽  
pp. 213-240 ◽  
Author(s):  
Michael D. Mumford ◽  
Rosemary A. Schultz ◽  
Judy R. Van Doorn
Keyword(s):  
Present Article ◽  
Research Needs ◽  
Critical Aspect ◽  
Theoretical Understanding ◽  
Alternative Models ◽  
Planning Processes ◽  
High Level ◽  
Key Questions

Planning is not only an aspect of our day-to-day lives, it represents a critical aspect of performance on many high-level tasks. Although few of us would dispute the need for planning, the psychology of planning remains relatively undeveloped. With this point in mind, the intent in the present article was to review the available literature on planning. The authors begin by examining alternative models of planning and delineating their implications for performance. Subsequently, the findings obtained in various studies of planning are reviewed with respect to 8 key questions ranging from when planning is useful to how errors in planning should be minimized. The implications of current answers to these questions are discussed in terms of research needs and development of a more comprehensive theoretical understanding of performance in planning.

The Gabrovo State men’s High School, in the Period of 1879–1902 and its Teachers-artists, who Have Received an Academic Education in Europe and Russia

2020 ◽  
Vol 4 (3) ◽  
Author(s):  
Nela Nedeva ◽  
◽  
◽  
Keyword(s):  
High School ◽  
Present Article ◽  
Western Europe ◽  
Academic Education ◽  
Time Period ◽  
History Of ◽  
High Level

The present article showcases the research done by the author on the drawing teachers of the Gabrovo State Boys’ High School during the 19-th and 20-th century. The study focuses on the teachers who have received academic education in Russia and Western Europe. The point of the article is to show the high level of teaching and erudition of the pedagogical staff during the examined time period. As proof the author has indicated information about their students who have left permanent traces in the history of painting even outside the borders of their country.

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