• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.25 no.11
• /
• pp.739-746
• /
• 2015

Several damage counting methods can be applied for the fatigue issues of a ground vehicle system using strain data and acceleration data is partially used for a high cyclic loading case. For a vibration test, acceleration data is, however, more useful than strain one owing to the good nature of signal-to-random ratio at acceleration response. The test severity can be judged by the fatigue damage and the pseudo-damage from the acceleration response stated in ISO-16750-3 is one of sound solutions for the vibration test. The comparison of fatigue damages, derived from both acceleration and strain, are analyzed in this study to determine the best choice of fatigue damage over multi-spectral input pattern. Uniaxial excitation test was conducted for a notched simple specimen and response data, both acceleration and strain, are used for the comparison of fatigue damages.

• The Journal of Fisheries Business Administration
• /
• v.42 no.2
• /
• pp.15-30
• /
• 2011

This study is designed to measure the relative efficiency of regional fishery cooperatives based on Data Envelopment Analysis(DEA) methods. Selecting 40 regional fishery cooperatives in Busan as Decision Making Units (DMUs), the study uses their panel data from 2007 to 2008 to rank the relative efficiency of the DMUs. First, the efficiency score of the DMUs are calculated using CCR, SBM, and super-SMB model. Within the model, input variables are the number of employees and area of fishery cooperatives. Output variables are the amount of deposit money, loan and profit. Based on the efficiency scores calculated from super-SMB model, the efficiency ranking of the DMUs is determined. Second, the differences in average efficiency calculated from the three DEA models are tested using a pair-wise mean comparison test. The results based on the efficiency scores evaluated from super-SMB model show that seven out of the forty DMUs are efficient; among the efficient DMUs, the DMUs that can be benchmarked for inefficient DMUs through the frequency analysis of reference set being identified. Third, the differences in average efficiency of the three DEA models between 2007 and 2008 are tested using pair-wise mean comparison test and the study estimates the efficiency change of the DMUs between 2007 and 2008 using Malmquist productivity index(MPI). Finally, the paper suggests an improved composite DMU superior to the inefficient DMUs evaluated by Super-SBM model.

• Korean Journal of Remote Sensing
• /
• v.35 no.1
• /
• pp.151-162
• /
• 2019

Surface temperature has been derived from the MODIS/ASTER airborne simulator (MASTER) mid-wave infrared single channel data using the MODerate resolution atmospheric TRANsmission (MODTRAN) radiative transfer model with input data including the University of Wisconsin (UW) emissivity, the National Centers for Environmental Prediction (NCEP) atmospheric profiles, and solar and line-of-sight geometry. We have selected the study area that covers some surface types such as water, sand, agricultural (vegetated) land, and clouds. Results of the current study show the reasonable geographical distribution of surface temperature over land and water similar to the pattern of the MASTER L2 surface temperature. The thorough quantitative validation of surface temperature retrieved from this study is somehow limited due to the lack of in-situ measurements. One point comparison at the Salton Sea buoy shows that the present estimate is 1.8 K higher than the field data. Further comparison with the MASTER L2 surface temperature over the study area reveals statistically good agreement with mean differences of 4.6 K between two estimates. We further analyze the surface temperature differences between two estimates and find primary factors to be emissivity and atmospheric correction.

• Journal of Ocean Engineering and Technology
• /
• v.38 no.1
• /
• pp.18-29
• /
• 2024

Waves are a complex phenomenon in marine and coastal areas, and accurate wave prediction is essential for the safety and resource management of ships at sea. In this study, three types of machine learning techniques specialized in nonlinear data processing were used to predict the waves of Korea waters. An optimized algorithm for each area is presented for performance evaluation and comparison. The optimal parameters were determined by varying the window size, and the performance was evaluated by comparing the mean absolute error (MAE). All the models showed good results when the window size was 4 or 7 d, with the gated recurrent unit (GRU) performing well in all waters. The MAE results were within 0.161 m to 0.051 m for significant wave heights and 0.491 s to 0.272 s for periods. In addition, the GRU showed higher prediction accuracy for certain data with waves greater than 3 m or 8 s, which is likely due to the number of training parameters. When conducting marine and offshore research at new locations, the results presented in this study can help ensure safety and improve work efficiency. If additional wave-related data are obtained, more accurate wave predictions will be possible.

• Human Ecology Research
• /
• v.53 no.2
• /
• pp.209-218
• /
• 2015

This study provides a basis for the development of lesson plans and teaching programs associated with the appearance in the adaptation of interpersonal relationships. This study was analyzed adolescents' body comparison and body satisfaction related in the adaptation of interpersonal relationships, and the effectiveness of self-esteem mediation. The survey was conducted among 587 adolescents in Gwangju. The data was analyzed using SPSS ver. 19.0 for Windows: frequency, means, factor analysis, Cronbach's ${\alpha}$, t-test, analysis of variance, Pearson correlation analysis, and regression analysis. The results indicated that body comparison and body satisfaction effected the adaptation of interpersonal relationships among adolescents consequently, it is necessary to develop lesson plans and teaching programs related to awareness, and improve appearance. A body comparison with similar aged people did not affect self-esteem; however, it is necessary to improve body satisfaction because it affects self-esteem. Self-esteem was also the mediating role between the adaptation of body satisfaction and interpersonal relationships, sub-factors, adaptation of relationships with friends, adaptation of relationship with teachers, adaptation of relationships with parents. It is important that body satisfaction and self-esteem is key factor in planning training programs, and improving the capacity of adolescents adaptation of interpersonal relationships.

• Journal of the Ergonomics Society of Korea
• /
• v.12 no.2
• /
• pp.85-91
• /
• 1993

Data obtained for sensory evaluation have a wide dispersion and fuzziness since human sensory organs are used as a means of measuring sensation instead of measuring instruments. Such dispersion and fuzziness are caused by all kinds of time error and have a great influence on the sensory evaluation, but most of previous papers not consider time errors. In this study, the comparative judgement capability of the evaluator was discriminated by means of the eigen- structure analysis on the premise that evaluation values of sensory evaluators obtained by a paired-comparison become different by the order of sample presentation.

• Journal of the Korean housing association
• /
• v.5 no.2
• /
• pp.109-117
• /
• 1994

The purpose of this study was to investigate the difference in water law and drinking water standards in Korea and five other countries. The documentary research method was used for this study and the Dong-A newspaper(1920-1993), journal and book related water pollution law were used as an analysis data. The results can be summarized as follow: 1. Law related water pollution in Korea was legislated last and characterized by frequent law revision in comparison with other countries. 2. Drinking water standards in Korea was strict in standard item and standard value.

• Journal of the Korean Statistical Society
• /
• v.23 no.1
• /
• pp.53-62
• /
• 1994

When a comparison is made with respect to the unknown best treatment, Hsu (1984, 1985) proposed the so called multiple comparisons procedures with the best in the analysis of variance model. Applying Hsu's results to the analysis of covariance model, simultaneous confidence intervals for multiple comparisons with the best in a balanced one-way layout with a random covariate are developed and are applied to a real data example.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.32 no.E
• /
• pp.59-66
• /
• 1990

Abstract The formulation of the probabilistic finite element method was briefly reviewed. The method was implemented into a computer program for frame analysis which has the same analogy as finite element analysis. Another program for Monte Carlo simulation of finite element analysis was written. Two sample structures were assumed and analized. The characteristics of the second moment statistics obtained by the probabilistic finite element method was examined through numerical studies. The applicability and limitation of the method were also evaluated in comparison with the data generated by Monte Carlo simulation.

• Proceedings of the KIEE Conference
• /
• 1987.07b
• /
• pp.962-964
• /
• 1987

In this paper a virtual route pacing control mechanism is introduced to the flow control of M-hop virtual route in the packet data network. The results described in this paper show us a comparison of the relationship between the throughput and the time-delay with the variation of the parameter, the normalized applied load. for the fixed window size.