scholarly journals Automatic Compensation of the Positional Error Utilizing Localization Method in Pipe

2021 ◽  
Vol 9 (6) ◽  
pp. 151-157
Author(s):  
Hirofumi Maeda
Keyword(s):  
Large Scale ◽  
Contact Point ◽  
Positional Error ◽  
Pipe Inspection ◽  
Automatic Compensation ◽  
Localization Method ◽  
Know How ◽  
Inspection Robot ◽  
Background Maintenance

Since 1965, a numerous number of cities implementing sewerage systems have increased rapidly throughout Japan, and sewerage development is considered to be becoming more widespread in various regions. However, with the increase of management facilities, the aging of facilities for long-term use is becoming more and more apparent. The standard expected durability of these pipes is approximately 50 years, but there is a tendency and a risk that the number of collapsed roads will increase rapidly 30 years after the pipes are laid. Against this background, maintenance of drainage and sewage pipes is critical and must be carried out continuously. Therefore, in recent years, investigation using robots have been actively conducted in order to reduce manual workload of the workers. However, these robots have a large-scale system as a whole, and as a result, they are poorly maintainable and expensive. Therefore, in this research, I have developed an autonomous and portable pipe inspection robot through the know-how on rescue robots which I have studied so far. However, for inspections using a pipe inspection robot, there is always the risk that the robot itself will tip over due to steps or small gaps at the joints of the pipes or slips caused by sludge. Therefore, to prevent tumbles and rollovers of the robot, I propose a localization method only by straight-driving control without relying on hardware. In addition, taking possible slips inside pipes into account, this method utilizes only acceleration sensor. In this study, localization method using only accelerometer mounted on the robot, which focuses on the relation between the pipe and the contact point of the tires, was shown as well as presenting a method using numerical analysis to derive the estimated values. Furthermore, it was confirmed that the estimation was stable as a result of an estimation experiment using autonomous small pipe inspection robot with and without a gradient (approx. 4/100) of a pipe, with a diameter of 189mm.

scholarly journals Participant Recruitment Challenges in Researching Peer Groups and Migration Retrospectively

2017 ◽  
Vol 13 (4) ◽  
pp. 48-69
Author(s):  
Paula Pustułka ◽  
Natalia Juchniewicz ◽  
Izabela Grabowska
Keyword(s):  
Longitudinal Study ◽  
Large Scale ◽  
Peer Group ◽  
Peer Groups ◽  
Participant Recruitment ◽  
Know How ◽  
Recruitment Challenges ◽  
Group Members ◽  
And Migration

This paper discusses the challenges of researching peer groups through a multi-focal, temporal lens in a retrospective manner. Embedded in a broader “Peer Groups & Migration” Qualitative Longitudinal Study (QLS), the article focuses on recruiting young respondents (aged 19-34 at present) who originally come from one of the three medium-sized towns in Polish localities and are either migrants or stayers connected to mobile individuals. The respondents are tracked retrospectively and asked to discuss their adolescence, as well encouraged to provide contacts to their youth Peer Group members. Based on fieldwork experiences and field access challenges, four models of recruiting migrants’ high school peer groups are presented. Furthermore, variants and rationales of non-recruitment are also provided. Focusing on the process of establishing a long-term and large-scale peer panel in the QLS, the paper contributes detailed know-how and strategies around participant recruitment.

scholarly journals Cornering Algorithm for a Crawler In-Pipe Inspection Robot

Symmetry ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 2016
Author(s):  
Liang Xu ◽  
Liang Zhang ◽  
Jinzhou Zhao ◽  
Kiwan Kim
Keyword(s):  
Weight Change ◽  
Large Scale ◽  
Good Stability ◽  
Elastic Structure ◽  
Pipe Diameter ◽  
Pipe Inspection ◽  
Optimization Analysis ◽  
Pipeline Inspection ◽  
Inspection Robot ◽  
Supporting Force

Based on the large-scale wall-pressing three-legged crawler pipeline inspection robot, our team proposed a cornering algorithm based on space constraints, that aims to better control the smooth operation of the pipeline robot in the pipeline. This algorithm is aimed at large robots that use an electric telescopic rod structure to replace the elastic structure on traditional small robots. The electric telescopic rod structure meets the large-scale weight change of the robot and provides sufficient supporting force. However, this structure also makes it difficult for the robot to automatically adapt to the change of pipe diameter and increases the difficulty of the robot’s control. In order to solve this problem and more accurately control the operation of the robot during cornering, this paper analyzes the space constraints of the robot when turning, the optimization analysis of the telescopic rod expansion and the ratio of the speed of each crawler, obtaining a stable turning algorithm for pipeline robots. The algorithm guarantees that the robot can provide sufficient support in the bend pipeline, and that it has good stability and mobility.

scholarly journals Studying Long-Term Large-Scale Change: Concluding Reflections on the Relevant Unit of Analysis

2009 ◽  
pp. 115-123
Author(s):  
Timothy Patrick Moran
Keyword(s):  
Systems Analysis ◽  
Large Scale ◽  
Word Choice ◽  
World Systems ◽  
Know How ◽  
Innovative Methodology ◽  
Large Scale Change ◽  
World Systems Analysis ◽  
Ontological Relationship

When I first received the papers as discussant for the ASA panel, Methodology for World-Systems Analysis (the papers that would come to constitute this journal’s special issue), I didn’t quite know how to proceed. In large part, the papers used innovative methodology to answer interesting substantive questions, so quality was not a question. The author’s were rigorous in how this methodology was applied, and creative in searching for and manipulating worldwide data, so no need to comment there. The problem was semantic. Not in the “petty dispute over word choice” sense of semantic, but in the ontological relationship between distinctive concepts and their intended (in this case theoretical) meaning.

Evolution of Large-Scale Coronal Structures

1994 ◽  
Vol 144 ◽  
pp. 29-33
Author(s):  
P. Ambrož
Keyword(s):  
Magnetic Field ◽  
Field Line ◽  
Large Scale ◽  
Coronal Magnetic Field ◽  
Source Surface ◽  
Solar Cycles ◽  
Characteristic Relationship ◽  
The Magnetic Field ◽  
Coronal Structures

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.

Computer Analyses in Preventive Health Research

1967 ◽  
Vol 06 (01) ◽  
pp. 8-14 ◽  
Author(s):  
M. F. Collen
Keyword(s):  
Medical Research ◽  
Preventive Medicine ◽  
Health Research ◽  
Large Scale ◽  
Preventive Health ◽  
New Era ◽  
Large Numbers ◽  
Normal Test ◽  
Computer Analyses

The utilization of an automated multitest laboratory as a data acquisition center and of a computer for trie data processing and analysis permits large scale preventive medical research previously not feasible. Normal test values are easily generated for the particular population studied. Long-term epidemiological research on large numbers of persons becomes practical. It is our belief that the advent of automation and computers has introduced a new era of preventive medicine.

(A review) Atlas of especially protected natural areas of Saint Petersburg / Ed. in chief V. N. Khramtsov, T. V. Kovaleva, N. Yu. Natsvaladze. St. Petersburg, 2013. 176 p.

2014 ◽  
pp. 124-129
Author(s):  
Z. V. Karamysheva
Keyword(s):  
Protected Areas ◽  
Large Scale ◽  
Natural Areas ◽  
Natural Protected Areas ◽  
Saint Petersburg ◽  
Natural Processes ◽  
Original Illustrations ◽  
Vegetation Maps ◽  
Protected Natural Areas

The review contains detailed description of the «Atlas of especially protected natural areas of Saint Petersburg» published in 2013. This publication presents the results of long-term studies of 12 natural protected areas made by a large research team in the years from 2002 to 2013 (see References). The Atlas contains a large number of the historical maps, new satellite images, the original illustrations, detailed texts on the nature of protected areas, summary tables of rare species of vascular plants, fungi and vertebrates recorded in these areas. Special attention is paid to the principles of thematic large-scale mapping. The landscape maps, the vegetation maps as well as the maps of natural processes in landscapes are included. Reviewed Atlas deserves the highest praise.

Etude de l'aménagement d'une forêt classée au Mali avec la participation des populations riveraines - Données du problème et éléments de méthodologie | A Study of the Management of a State-Owned Forest in Mali with the Participation of the Population Living nearby - Issue under Investigation and Elements of Methodology

2000 ◽  
Vol 151 (3) ◽  
pp. 80-83
Author(s):  
Pascal Schneider ◽  
Jean-Pierre Sorg
Keyword(s):  
Natural Resources ◽  
Research Methodology ◽  
Large Scale ◽  
Environmental Context ◽  
Forest Resources ◽  
The State ◽  
Commercial Use ◽  
Economic Context ◽  
The People

In and around the state-owned forest of Farako in the region of Sikasso, Mali, a large-scale study focused on finding a compromise allowing the existential and legitimate needs of the population to be met and at the same time conserving the forest resources in the long term. The first step in research was to sketch out the rural socio-economic context and determine the needs for natural resources for autoconsumption and commercial use as well as the demand for non-material forest services. Simultaneously, the environmental context of the forest and the resources available were evaluated by means of inventories with regard to quality and quantity. According to an in-depth comparison between demand and potential, there is a differentiated view of the suitability of the forest to meet the needs of the people living nearby. Propositions for a multipurpose management of the forest were drawn up. This contribution deals with some basic elements of research methodology as well as with results of the study.

Investigations on the filtration of natural aquatic suspensions supported by dosing small amounts of Fe(III)-salts (βFe ≤ 0.1 mg.L-1): mode of action and basic design criteria

2002 ◽  
Vol 2 (2) ◽  
pp. 91-98
Author(s):  
R. Winzenbacher ◽  
R. Schick ◽  
H.-H. Stabel ◽  
M. Jekel
Keyword(s):  
Large Scale ◽  
Suspended Solids ◽  
Iron Hydroxides ◽  
Essential Step ◽  
Iron Salts ◽  
Alkaline Earths ◽  
Co Precipitation ◽  
Solid Liquid ◽  
Solid Liquid Separation

Improved removal of particles during the treatment of natural aquatic suspensions has been achieved by pre-ozonation and the addition of small quantities of iron salts (βFe ≤ 0.1 mg.L-1; “Fe(III)-assisted filtration”) followed by rapid filtration. As shown by investigations on a large-scale installation at Lake Constance Water Supply, this procedure reliably reduces suspended solids by at least 2-3 powers of ten in long-term use. However, the high efficacy of Fe(III)-assisted filtration cannot be explained on the basis of known coagulation mechanisms (like adsorption-charge neutralization, co-precipitation). Instead, the essential step was found to be the conditioning of the filter medium by coating it with colloids containing Fe(OH)3, and this “Fe coating” process occurs only in the presence of alkaline earths (especially Ca2+). According to further experiments, the enhanced solid-liquid separation was ultimately traced to chemical interactions such as the formation of calcium-organic association structures between the iron hydroxides and other solids. For design of Fe(III)-assisted filtration steps, finally, a βCa/DOC ratio above 40 mg.mg-1 and pre-oxidation with ozone dosages not exceeding 2 mg O3/mg DOC was recommended.

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