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The purpose of this paper is to propose a method of qualitative ferrographic analysis by quantitative parameters of wear debris characteristics.

The amount of the wear debris needed for analysis on the ferrogram made by rotary ferrograph is discussed based on the theory of debris group. Quantitative parameters are constituted to express the characteristics of wear debris group, and correlation coefficients are employed to establish the relationship between wear debris and wear condition. The reliability of the method was verified by wear test experiments and ferrographic analysis.

The wear condition of machines should be determined by studying all the debris together as a group rather than by focusing on individual debris. In the proposed method, the qualitative analysis result is obtained by synthetic analysis of quantitative parameters of wear debris characteristics using a computer program, which makes the judgment of the wear system condition more objective and precise.

In the procedure of wear condition monitoring by the proposed method, because the weight factors and correlation coefficients introduced in this paper are determined according to the experiences deriving from practice among mining machinery, further rectifications may be needed if they are applied to other industrial field.

The paper illustrates a more objective and precise ferrographic analysis method for wear condition monitoring.

Reports on the study of wear debris in the early 1980s organized by the Institution of Mechanical Engineers. Describes the use of Ferrography, spectrographic oil analysis, X‐ray fluorescence, inductive, magnetic and ultrasonic methods of debris detection with some examples of wear limits.

The dependency on human expertise for analysis and interpretation is the main reason for wear debris analysis not being used in industry to its full potential and becoming one of the most powerful machine condition monitoring strategies. The dependency on human expertise makes the interpretation and result subjective in nature, costly and time consuming. The purpose of this paper is to review work being done to develop an automatic, reliable and objective wear particle classification system as a solution to the above problem. At the same time it also aims to discuss some common off line test methods being practiced for wear debris analysis.

Computer image analysis is a solution for some of the problems associated with the conventional techniques. First it is tried to efficiently describe the characteristics of computer images of different types of wear debris using a few numerical parameters. Then using some Artificial Intelligence tools, the wear particle classification system can be developed.

Many shape, size and surface parameters are discussed in the paper. Out of these, nine numerical parameters are selected to describe and distinguish six common type of wear debris. Once the type of debris is identified, the mode of wear and hence the machine condition can be assessed.

The present process of fault and condition monitoring of an equipment by wear debris analysis involves human judgment of debris formations. A set‐up standard for comparison of debris will enable the maintenance team to diagnose faults in a comparatively better way.

The aim of this paper is to discuss the difficulties in identifying wear particles and finding out the exact health of equipment, which, due to its subjective nature, is influenced by human errors. An objective method with certain standards for classification of wear particles compatible with an artificial intelligence system will yield some flawless results of wear debris analysis, which has not been attempted in the past as per available literature.

The purpose of this paper is to show the development of an image processing-based portable equipment for an automatic wear debris analysis. It can analyze both the qualitative and quantitative features of machine wear debris: size, quantity, size distribution, shape, surface texture and material composition via color.

It comprises hardware and software components which can take debris in near real-time from a machine oil sump and process it for features diagnosis. This processing provides the information of the basic features on the user screen which can further be used for machine component health diagnosis.

The developed system has the capacity to replace the existing off-line methods due to its cost effectiveness and simplicity in operation. The system is able to analyze debris basic quantitative and qualitative features greater than 50 micron and less than 300 micron.

Wear debris basic features analysis tool is developed and discussed. The portable and near real-time analysis offered by the discussed work can be more technically effective as compared to the existing off-line and online techniques.

Fretting wear exists widely in the field of matching mechanical parts whereas previous research studies mostly focus on the point contact through a ball-plate tribometer. This paper aims to study the influence of wear debris on the fretting wear characteristics of the nitrided medium carbon steel under line contact condition at elevated temperature.

Fretting wear behavior of the nitrided medium carbon steel was experimentally investigated under line contact condition at elevated temperature and different normal loads without lubrication. Wear loss, worn surface and wear debris were studied to analyze the wear mechanism of nitrided steel.

The results showed that surface hardness of the medium carbon steel was notably improved because of the generation of a 230 µm nitrided case. Wear loss increased with the normal load, which was associated with the damage of a thin solid film formed by the wear debris, consisting of iron oxides and chromium oxide rather than only iron or iron oxides. The wear debris became partially amorphous and spherical because it was trapped within the contact interface and was ground, rolled, oxidized under line contact conditions. The spherical wear debris acted as a third body and formed a lubricating film between the contact faces. This lubricating film helped to stabilize the friction coefficient and reduced the wear rate, which further caused the acceleration of wear volume to gradually decrease. The wear mechanisms of the nitrided steel were oxidation wear, abrasive wear and fatigue spalling of the oxide layer.

The findings are helpful to understand the fretting wear behavior of the friction pair under line contact and enrich the fretting tribology theory.

Lifelines (also referred to as critical infrastructure) are referred to here as the essential infrastructure and services that support the life of our community. In a disaster response and recovery situation, provision of Lifelines, is essential. New Zealand has several mechanisms to improve the responses of lifeline service providers in a disaster situation, including pre‐event planning and coordination groups and legislative provisions for timely response in an emergency. Currently, waste management is not formally included in either the coordination process or the legislative provisions for Lifelines. This paper aims to address whether or not waste management should be included in these.

Qualitative and semi‐qualitative matrix‐based assessments were used to determine the relative importance of provision of waste management services in a disaster‐recovery situation.

The paper argues that waste management should be included in Lifeline planning in New Zealand. Organisational complexity in the waste management system and the likely need to expand pre‐disaster waste management services to deal with large amounts of disaster generated waste, however, mean that inclusion in the legislative provisions for Lifeline service providers would be challenging.

The research context is specific to New Zealand; however, the general challenges, principles and overall approach and may be transferable to other jurisdictions.

Organisational and regulatory approaches recommended in this paper, if adopted, will help waste and emergency managers respond and recover more effectively in a disaster situation.

This paper is the first to attempt to examine in detail the importance of waste management on disaster recovery in New Zealand. The findings of the paper are of relevance to countries with similar organisational and legal structures.

The probability distribution of major length and aspect ratio (major length/minor length) of wear debris collected from gear oil used in planetary gear drive were analysed and modelled. The paper aims to find an appropriate probability distribution model to forecast the kind of wear particles at different running hour of the machine.

Used gear oil of the planetary gear box of a slab caster was drained out and charged with a fresh oil of grade (EP-460). Six chronological oil samples were collected at different time interval between 480 and 1,992 h of machine running. The oil samples were filtered to separate wear particles, and microscopic study of wear debris was carried out at 100X magnification. Statistical modelling of wear debris distribution was done using Weibull and exponential probability distribution model. A comparison was studied among actual, Weibull and exponential probability distribution of major length and aspect ratio of wear particles.

Distribution of major length of wear particle was found to be closer to the exponential probability density function, whereas Weibull probability density function fitted better to distribution of aspect ratio of wear particle.

The potential of the developed model can be used to analyse the distribution of major length and aspect ratio of wear debris present in planetary gear box of slab caster machine.

Landslides are common occurrences in the US West. Some of these events cause injury and even death to visitors to these landscapes. Investigates changes in visitor perceptions of the likelihood and location of landslide events in Glacier National Park, Montana, in the wake of a series of hazardous debris flow occurrences. The initial surveying was completed at the Logan Pass Visitor Center on 17 July 1998 using a specially created survey. On 28 July 1998, a series of debris flows crossed Going‐to‐the‐Sun Road and trapped several cars between flow deposits. The road was blocked for more than 24 hours as debris was cleared. In an attempt to examine perception differences after the slide event visitors were resurveyed at the same location on 30 July 1998. Results from statistical analyses and maps created from the survey revealed no significant changes in public perception of danger to self from landslides, nor in the perceived locations of where landslides may occur.

In light of the discussions on outer space property management, this conceptual review paper aims to discuss and evaluate if, when and under which conditions certain land management and property right frameworks can apply to allocate and/or restrict property rights in outer space.

This paper applies a pragmatic review approach which seeks to better understand if and how the basic tenets of the land management frameworks could better shape and revise the challenges in outer space regulations.

Despite the fact that regulatory guidelines on outer space rights are existing, the analysis shows that these lack a number of practical tools and measures aiming at intervening if stakeholders do not follow the rules. With the use of land management frameworks, it is possible to derive policy options for making the outer space management more practical and action-oriented, in particular for the removal of space debris. These include amongst others more attention for formulating global public restrictions in outer space, incorporating regulatory guidelines for accessing open space regimes, addressing responsiveness and robustness in adherence and compliance to regulations

Given the conceptual and discursive character of the paper, there are no specific empirical data, yet several recommendations for further research include expanding the boundary work between the land management and regulatory outer space domain.

The insights derived from land management and real estate related property theories could potentially provide new starting points for (re)formulating the regulatory framework for outer space property discourses.

Interpreting the outer space regulations from known and practiced land management perspective helps to bridge the policy–society knowledge and necessity gap on outer space activities.

The specific land management perspective and discursive analysis on outer space debris provide new options for devising and extending regulatory guidelines for assigning responsibilities on outer space debris and debris rights, restrictions and responsibilities.

On September 9, 2018, Hurricane Irma swept across south Florida, leaving a path of destruction across the entire state. Miami-Dade County, at the southern tip of the state, avoided a direct hit. However, the storm left the county and its dozens of municipalities with gigantic mounds of storm debris. As the weeks went by, the piles festered and frustration with the pace of the clean-up mounted. Two dump sites in particular drew the attention of media and community activists: a park ringed by single family homes in Liberty City, a black community in the heart of Miami; and historic Virginia Key, the only beach open to black citizens under Jim Crow segregation. This research examines three narratives -- media coverage, official explanations from local governments, and reactions on social media -- as a way to investigate how the dumping of storm debris in black spaces was justified, interrogated, and contested in the aftermath of one of the worst hurricanes to strike Miami-Dade County in over a decade. Climate change models predict the increasing frequency of super storms like Irma, and discussions of how coastal cities respond in terms of infrastructure and resiliency are growing. This investigation looks at two components of this response that have not been as widely considered: what are the institutional and citizen responses in the aftermath of these storms, and how will issues of race and historic geographic marginalization be either acknowledged or ignored as the problems associated with climate change grow ever more acute and pressing.