• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2000.06a
• /
• pp.62-67
• /
• 2000

This paper was undertaken to do morphological analysis of wear debris for slipper-Pad of hydraulic rotary acuator. The lubricating wear test was performed under different experimental conditions using the wear test device and wear specimens of the pin on disk type was rubbed in paraffinic base oil by three kinds of lubricating materials, varying applied load, sliding distance. The four shape parameters(50% volumetric diameter, aspect, roundness and reflectivity) are used for morphological analysis of wear debris. The results showed that the four shape parameters of wear debris depend on a kind of the lubricating condition. It was capable of presuming wear volume for slipper-pad of hydraulic rotary acuator on driving time.

• Journal of Advanced Marine Engineering and Technology
• /
• v.33 no.7
• /
• pp.1044-1051
• /
• 2009

During contact between surfaces, there is wear and the generation of wear. The particles contained in the lubricating oil carry detailed and important monitoring information about the condition of the machine. Therefore, this paper was undertaken for the Ferrography system of wear debris generated from a lubricated moving machine surface. The lubricating wear test was performed under different experimental conditions using the Falex wear test of the Pin and V-Block types by Ti(C,N) coated. It was shown from the test results that wear particle concentration(WPC), wear severity index(Is) and size distribution have come out all higher with increases in sliding friction time. With the Ferrogram thin leaf wear debris as well as ball and plate type wear particles were observed.

• Fashion & Textile Research Journal
• /
• v.15 no.2
• /
• pp.268-276
• /
• 2013

This study identifies how people use bicycle wear, complaints about bicycle wear, and functions required for bicycle riding. This survey was conducted with bicycle club members (men and women) in their twenties to sixties who ride bicycles on a regular basis. A total of 373 subjects responded to questionnaires and 326 responses were used for further data analysis. The data was analyzed by descriptive analysis, multiple response analysis, crosstabulation analysis, factor analysis, reliability analysis, and one-way ANOVA. The results are as follow: First, the people surveyed were primarily men, young adults and middle-aged people. They ride bicycles mainly to participate in club activities, to exercise, and to spend their spare time with a well-being trend that focuses on leisure and health. Second, they often utilize bicycle wear when they ride bicycles. They are aware of bicycle wear brands. In addition, a majority have purchased bicycle wear that shows a very high awareness of bicycle wear. Third, as for complaints about bicycle wear worn when riding bicycles, a majority of people answered that the waist part of the top pulls up and they feel sore with the bottom part of the pants when riding bicycles for a long time. They also answered that it is inconvenient to put belongings in both tops and pants. Fourth, there is a high demand for safety-related functions for bicycle riding in regards to the functions required for bicycle wear. In addition, a majority of the members showed a customer awareness of functional bicycle wear and intended to purchase bicycle wear equipped with smart functions.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.40 no.6
• /
• pp.547-555
• /
• 2016

The wheel wear of a railway vehicle is mainly generated when maneuvering on a curved track. The change in the wheel profile affects the dynamic stability of the vehicle. In this analysis, the wheel wear volume was calculated while changing the velocity and radius of the curve to analyze the wear characteristics of a wheel at a curved section. The wear index was calculated from a vehicle dynamic analysis based on a multibody dynamics analysis and wear volume from a wear model by British Rail Research. The wear volume at a radius of 300 m is dominant compared with other radii. The wear volume was calculated by assigning different coefficients of friction to the tread and flange of the wheel to investigate the effect of lubrication on the wear characteristics. The effect of the improvement by lubrication is calculated by varying the radius of the track, and is assessed on an actual urban railway section.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.5
• /
• pp.835-841
• /
• 1997

Microscopic examination of the morphology of wear debris is an accepted method for machine condition and fault diagnosis. However wear particle analysis has not been widely accepted in industry because it is dependent on expert interpretation of particle morphology and subjective assessment criteria. This paper was undertaken to analyze the morphology of wear debris for machine condition diagnosis of the lubricated moving surfaces by image processing and analysis. The lubricating wear test was performed under different sliding conditions using a wear test device made in our laboratory and wear testing specimen of the pin-on-disk-type was rubbed in paraffine series base oil. In order to describe characteristics of debris of various shape and size, four shape parameters (50% volumetric diameter, aspect, roundness and reflectivity) have been developed and outlined in the paper. A system using such techniques promises to obviate the need for subjective, human interpretation of particle morphology in machine condition monitoring, thus to overcome many of the difficulties in current methods and to facilitate wider use of wear particle analysis in machine condition monitoring.

• Fashion & Textile Research Journal
• /
• v.17 no.3
• /
• pp.440-446
• /
• 2015

This study identified active senior women's wearing and the purchase situation of bicycle wear to develop functional bicycle wear that can satisfy active senior consumers. The survey was conducted for women in their fifties and sixties who ride bicycles on a regular basis. A total of 119 questionnaires were used for data analysis excluding incompletely replied questionnaires. Data was analyzed by descriptive analysis, frequency analysis and cross analysis. The results are as follows. First, 50's individuals represented 60% of this survey who continuously rodebicycles for 5 years or more. The purpose of riding bicycle was exercise, leisure and club activities. Second, they wore bicycle wear while riding due to activity, functionality and safety. There is also a requirement to manufacture comfortable bicycle wear easy to put on and take off and for old people. Third, considering the purchase situation of bicycle wear, the respondents had difficulties buying bicycle wear due to price. It is necessary to have bicycle wear at a reasonable price. Fourth, the most necessary functionsforbicycle wear materials were ventilation and durability. A major function needed for future developmentwill bethermoregulation.

• Structural Engineering and Mechanics
• /
• v.31 no.1
• /
• pp.57-74
• /
• 2009

Power signals resulting from spindle and feed motor, present a rich content of physical information, the appropriate analysis of which can lead to the clear identification of the nature of the tool wear. The partial least-squares regression (PLSR) method has been established as the tool wear analysis method for this purpose. Firstly, the results of the application of widely used techniques are given and their limitations of prior methods are delineated. Secondly, the application of PLSR is proposed. The singular value theory is used to noise reduction. According to grey relational degree analysis, sample variable is filtered as part sample variable and all sample variables as independent variables for modelling, and the tool wear is taken as dependent variable, thus PLSR model is built up through adapting to several experimental data of tool wear in different milling process. Finally, the prediction value of tool wear is compare with actual value, in order to test whether the model of the tool wear can adopt to new measuring data on the independent variable. In the new different cutting process, milling tool wear was predicted by the methods of PLSR and MLR (Multivariate Linear Regression) as well as BPNN (BP Neural Network) at the same time. Experimental results show that the methods can meet the needs of the engineering and PLSR is more suitable for monitoring tool wear.

• Computers and Concrete
• /
• v.31 no.2
• /
• pp.163-171
• /
• 2023

Face gear transmission is widely used in aerospace shunt-confluence transmission system. Tooth wear is one of the main factors affecting its bearing transmission performance. Furthermore, the installation errors of face gear are inevitable. In order to study the wear mechanism of face gear tooth surface with installation errors, based on tooth contact analysis numerical method and Archard wear theory, the UMESHMOTION subroutine in ABAQUS is developed.Combining with Arbitrary Lagrangian-Eulerian adaptive mesh technology, the finite element mesh wear model of abraded face gear pair is established.The preprocessing conditions are set to generate the inp files.Then,the inp files for each corner are imported and batch processed in ABAQUS.The loading tooth contact problem at each rotation angle is solved and the load distribution coefficient among gear tooth, tooth root bending stress, tooth surface contact stress and loaded transmission error are obtained. Results show that the tooth root wear is the most serious and the wear at the pitch cone is close to 0.The wear law of tooth surface along tooth width direction is convex parabola and the wear law along tooth height direction is concave parabola.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.24 no.6
• /
• pp.838-849
• /
• 2000

The purpose of this study was to investigate use and purchase behavior of sleeping wear for summer. Subjects in this study were composed of 591 males and females aged from twenties to fifties, living in Taejon and Chongju. For data analysis, descriptive analysis, $\chi$$^2$-test, t-test, ANOVA, and factor analysis were used. The results are as follows. First, subjects used sleeping wear(a night gown and pajamas), and home wear(T-shirts and sweat suit with zippered top) with similar rates. The subjects, who are females, married, older and have professional jobs, owned sleeping wear such as a night gown and pajamas more than home wear. Also, the mean of using pajamas was the highest, and they were satisfied with them more than others who didn't wear them. Second, one-third of consumers purchased sleeping wear once a year in a specialty store. Consumers mainly searched for information regarding sleeping wear in the display section. Most consumers weren't influenced by others when they made their purchases. When consumers decided to purchase a product, they considered six criteria such as fabric/management, wearing/fitness, esthetic, service, symbolic status, and economic for evaluating. Among them, the factor wearing/fitness was considered the most important. These results imply that consumers would be conscious of sleeping wear even though sleeping wear and home wear are used interchangeably. In addition, consumer behavior concerning sleeping wear is different from their characteristics such as sex, age, occupation, the level of education, and marital state. Therefore, the markets with sleeping wear would be able to be segmented based on consumers’characteristics. Also, marketers should focus on distribution channels to reform the markets of sleeping wear, that is, they may offer products in specialty stores. Additionally, market managers would be able to concentrate on visual merchandising in stores in order to increase brand awareness and market share.

• KSTLE International Journal
• /
• v.2 no.1
• /
• pp.35-39
• /
• 2001

In this paper, statistical approach is undertaken to investigate the classification of wear debris which is the key function of objective assessment of wear debris morphology. Wear tests are run to produce various kinds of wear debris. The images of wear debris from wear tests are captured with image acquisition equipment. By thresholding, two-dimensional binary images of wear debris are made and, then, morphological parameters are used to quantify the images of debris. Parametric and nonparametric discriminant method are employed to classify wear debris into predefined wear conditions. It is demonstrated that classification accuracy of parametric and nonparametric discriminant method is similar. The selected use of morphological parameters by stepwise discriminant analysis can generally improve the classification accuracy of parametric and nonparametric discriminant method.