• Journal of the Korean Society of Safety
• /
• v.12 no.3
• /
• pp.3-9
• /
• 1997

The strength of material is scattered owing to the inhomogenity of microstructure, in spite of the same material. Therefore, in order to design the mechanical structure with the reliability engineering, it is important to grasp the statistic nature of material strength. In this paper, effects of grain sizes for the statistical nature of the fatigue crack growth was discussed. And the statistical of mechanical properties was compared with statistical nature of the fatigue crack growth rate.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.7
• /
• pp.2141-2147
• /
• 1996

The strength of material is scattered owing to the inhomogenity of microstructure, in spite of the same material. Therefore, in order to design the mechanical structure with the reliability engineering, it is important to grasp the statistical nature of material strength. In this paper, effects of grain sezes for the statistical nature of the fatigue crack growth was discussed. And the statistical nature of mechanical properties was compared with the statistical nature of the fatigue crack growth rate.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.2
• /
• pp.511-519
• /
• 1996

An investigation was conducted to study the statistical nature of tensile strength and static fracture toughness of carbon fiber reinforced plastics(CFRP) materials. A good understanding of statistical aspects of strength data is essential for the successful application of such materials because these composites unpossess material uniformity as compared with conventional metallic materials. In this paper, a statistical approach based on Weibull distribution was applied to the test data to evaluate the dispersion in the tensile strength and static fracture toughness by the change of stacking method and test temparature of the CFRP materials.

• Industrial Engineering and Management Systems
• /
• v.15 no.4
• /
• pp.432-445
• /
• 2016

A random profile is the result of a process, the output of which is a function instead of a scalar or vector quantity. In the nature of these objects, two main dimensions of "functionality" and "randomness" can be recognized. Valuable researches have been conducted to present control charts for monitoring such processes in which a regression approach has been applied by focusing on "randomness" of profiles. Performing other statistical techniques such as hypothesis testing for different parameters, comparing parameters of two populations, ANOVA, DOE, etc. has been postponed thus far, because the "functional" nature of profiles is ignored. In this paper, first, some needed theorems are proven with an applied approach, so that be understandable for an engineer which is unfamiliar with advanced mathematical analysis. Then, as an application of that, a statistical test is designed for mean of continuous random profiles. Finally, using experimental operating characteristic curves obtained in computer simulation, it is demonstrated that the presented tests are properly able to recognize deviations in the null hypothesis.

• Hwankyungkyoyuk
• /
• v.13 no.1
• /
• pp.53-64
• /
• 2000

The objective of this study is to identify the relationship between the individual's environmental behaviors and personal experiences about nature. Interview surveys were done to collect data from 237 adults who live in the metropolitan area of Seoul. Statistical methods such as mean, standard variables, 1-test, ANOVA, multiple regression analysis, GLM(general linear model) were employed to analyze the data using SPSS program. The major results were as follows: 1. The group who has higher nature experience score also has significantly higher environmental behaviors score. 2. Most of nature experiences show significant relationship with positive environmental behaviors. 3. In each demographic group, nature experiences were related to positive environmental behaviors.

• Journal of the Korean Statistical Society
• /
• v.4 no.2
• /
• pp.97-109
• /
• 1975

To gain knowledge about the unknown state $\theta$ of nature, we perform experiments. Sufficiency of an experiment for another experiment has been introduced for the comparison of experiments. The knoledge before and after an experiment makes it possible to discuss the amount of information provided by the experiment.

• Journal of the Korea Society for Simulation
• /
• v.4 no.1
• /
• pp.113-119
• /
• 1995

In 3D computer graphics, fractal techniques have been applied to terrain models. Even though fractal models have become popular for recreating a wide variety of the shapes found in nature, a specific 3D terrain model such as Uleung Island could not be formulated by statistical fractals easily owing to the random effects. However, by locating the midpoints on the edges and the surface of a specific terrain such as Uleung Island, a similar shape of the terrain model can be simulated. This paper shows the way of simulating 3D Uleung Island terrain model by the statistical fractals wherein the subdivision algorithm is used.

• International journal of advanced smart convergence
• /
• v.8 no.3
• /
• pp.123-130
• /
• 2019

In the study, we suggest that the activation plan of the public nature burial in the capital area through funeral information system as follows. First, according to the report on the social survey announced by the National Statistical Office in December 2017, the Korean people's preference of nature burial was 43.6% while the actual utilization rate of national nature burial in 2017 was only 8.8%, which showed a huge gap between preference and utilization rate of nature burial. Therefore, through the activities to improve the awareness of nature burial by performing the national promotion and education, and also the investment for the expansion or improvement of nature burial facilities in the level of central government and local government, the preference of nature burial should be led to the actual demand. Second, during the period from 2011 to 2018, the utilization rate of public nature burial in the capital area was annually increased by average 26.9%, which showed the huge increase of demand for nature burial. Thus, each local government should carry forward the policies for expanding the supply of public nature burial focusing on the woodland burial showing the high preference of users of public nature burial. Third, even though the public cremation facilities are installed or operated by local governments in the capital area, Seongnam City without the public cremation facilities should install the public nature burial for the enhancement of users convenience by providing the One Stop Total Funeral Service.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.05c
• /
• pp.221-224
• /
• 2001

In connection with the monitoring of insulation degradation of large power apparatus in order to predict their unexpected service failures, a statistical treatment, such as phase resolved partial discharge analysis(PRPDA), has been established for the on-line monitoring system during the past decades. However, this method has shown some inconveniences to distinguish the nature of the PD source in power apparatus. In this regard, a novel approach based on the chaotic analysis(CAPD) is proposed describing the fundamental ideas, outcomes and different view points from conventional PRPDA. In order to make a model for the possible defects causing sudden failures in service, several types of specimen were prepared. And partial discharge signals, originated from those samples, were measured and analysed by means of PRPDA and CAPD respectively. Throughout this paper, it seems that the correlation between the consecutive PD pulses depending on the nature of PD could be investigated by CAPD. Therefore, it could be considered that the nature of PD source can be distinguished more distinctively when the PRPDA is combined with CAPD.

• Proceedings of the IEEK Conference
• /
• 2001.09a
• /
• pp.975-979
• /
• 2001

In connection with the monitoring of the insulation degradation of large power apparatus in order to predict their expected service failures, a statistical treatment, such as phase resolved partial discharge analysis (PRPDA), has been established for the on-line monitoring system during the past decades. However, this method has shown some inconveniences to identify the nature of the PD source in power apparatus. In this regard, a novel approach based on the chaotic analysis (CAPD) is proposed describing the fundamental ideas, outcomes and different viewpoints from the conventional PRPDA. As a model for the possible defects causing sudden failures in service, three types of specimen are prepared. And partial discharge signals, originated from those samples, are measured and analyzed by means of CAPD. Throughout this work, it seems that the correlation between the consecutive PD pulses, depending on the nature of PD, could be clarified by CAPD. Thereffre, it could be considered that the nature of PD source can be identified more distinctively when the CAPD is combined with PRPDA.