• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.123-129
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• 2013

Among various manual materials handling tasks, pushing/pulling was known to be one of the risk factors for the low back and shoulder musculoskeletal disorders (MSDs). This study was conducted to find out an optimal solution set of the handle height and distance for 4-wheel cart with two vertical handles. Ten male college students participated in the pushing force measurement experiment. The face-centered cube design, one of the central composite designs, was applied for the experiment, and the isometric voluntary pushing force was measured in 9 treatment conditions. The second order response surface model was predicted by using the pushing strength as a response variable, and the handle height and distance as independent factors. According to the 2nd order response model, the handle height and distance showed nonlinear relationship with the isometric pushing strength. To maximize the 2nd order response model (pushing force), the handle height and distance were optimized. The optimal handle height was 'xyphoid process height - stature', and the optimal handle distance was '$1.25{\times}shoulder$ width'. When calculated using the anthropometric data of the subjects of this study, the optimal handle height was $115.4{\pm}3.4$ cm, slightly higher than the elbow height, and the handle distance was $52.9{\pm}2.3$ cm.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.371-374
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• 2015

Classical Cepheids (hereafter Cepheids) belong to a class of important variable stars that can be used to determine distances to nearby galaxies via the famous period-luminosity (PL) relations, i.e. the Leavitt Law. In turn, these distances can then be used to calibrate a host of secondary distance indicators located well within the Hubble flow, and ultimately determine the Hubble constant in a manner independent of the Cosmic Microwave Background (CMB) measurements. Some recent progress in determining the Hubble constant to within ~ 3% level via the Cepheid-based distance scale ladder (the SH0ES and the Carnegie Hubble Program) were first summarized in this Proceeding, followed by a brief discussion on the prospect of using ultra-long period Cepheids (ULPC) in future distance scale work. ULPC are those Cepheids with periods longer than 80 days, which seem to follow a different PL relation than their shorter period Cepheids. It has been suggested that ULPC can be used to determine the Hubble constant in "one-step". However, based on the two ULPCs found in M31, it was found that the large dispersion in derived distance moduli leads to a less accurate distance modulus to M31 compared to the classical Cepheids. This finding might raise an alert regarding the use of ULPCs in future distance scale work.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.651-653
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• 2000

In this study, a distance-measurement system was proposed by using principle of the Michelson Interferometer and a fundamental research was carried out. In case of the rnichelson interferometer, relativity distance was measured by relativity-difference of two course of light. But wavelength of light source were changed in this system in order to use interference phenomenon of michelson interferometer in measuring absolutely distance. Wavelength of input signal were changed periodically and were interfered electrically. So absolute distance can be calculated by using $\Delta\lambda$ and measuring $\eta\Delta$ in electric interference. Nose by a external factor was small in this system because a absolutely distance was measured by phase difference. And a dispersion of noise was small in pulse-echo response because a error was occurred in range of phase difference of signal. Also very wide range can be measured by only single system because informations of distance were acquisited in wavelength level.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.65-76
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• 2018

This study aims to evaluate the legibility distances of variable speed limit sign(VSL) for different sizes, luminances, and fog conditions through a field experiment. For this, extensive fog simulated environment has been constructed, and legibility distances are tested and recorded among test subjects for different luminances and sizes of VSL in control. Results showed that legibility distance increased as the size of VSL increased in the given illumination conditions, but it was not an exact linear trend. The size was also an important factor for determining legibility distance as the fog density increased, especially heavy fog conditions. In addition, the legibility distance also increased as the given illumination levels of VSL improved.

• Journal of Distribution Science
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• v.13 no.8
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• pp.73-80
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• 2015

Purpose - This study's objective is to analyze the content of the communications between users and producers based on the construal level theory. User generated content refers to content created in an online-based service where users and producers communicate interactively with each other. In a user generated content platform, the messages sent and received between the many players, the users and producers who use the content, may be analyzed at the psychological level based on construal level theory. Research design, data, and methodology - This study gathered user and producer participation through a snow-bowling sampling method. The data analyzed includes 125 video clips and 2,912 comments. The period of the data collection was from September 2014 to December 2014. The collected data was analyzed using a t-test and two-way ANOVA. Results - This study obtained the following research results. First, users who were a short social distance from producers responded to user participatory activities stated in concrete language rather than abstract language. In contrast, users who were at a longer social distance from producers tended to respond to the content requesting user participation through abstract language. Second, if users and producers were at a short social distance from each other, user preference increased more when a producer response to user participation was expressed concretely rather than when it was expressed abstractly. In contrast, if the users were at a longer social distance, users' preferences increased more when producer response was expressed abstractly rather than when it was expressed concretely. Conclusion - This study found that the effect of suitability, in which the social distance and the content were in congruence at the construal level, could be observed. Therefore, based on this, academic and practical implications were drawn. The three main insights of the study are as follows. First, firms can use psychological factors to analyze the message content of users in their distribution platforms. This study reveals managerial implications for marketing managers who want to take make use of this analysis of user and producer communications. This study indicates that the main factors include the concrete and abstract scores and social distance between users and producers. Second, we also provide the strategic guidelines to maximizing user preferences and other outcomes. The main dependent variable in this study is the user preference shift; the variable increases through the congruence effect; and the construal level is determined by the social distance between the users and producers and the type of producer response. The outcomes here from users can be utilized to develop several systemic strategies. One process to use the outcomes could be: (1) firms could measure the users and producers social distance; (2) calculate the concreteness or abstractness of the messages; and, (3) predict the user preference outcomes by the congruence between user and producer social distance and the abstractness or concreteness of the message content.

• Journal of the Korean Data and Information Science Society
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• v.15 no.1
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• pp.95-105
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• 2004

The main characteristic of the ordinal scale is that its categories have a logically or continuously ordered relationship to each other. A continuous type permits measuring degrees of differences among categories. Also, the specific amount of differences is important. In this paper we consider the scoring method using a dummy variable based on distance among categories.

• Proceedings of the IEEK Conference
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• 2000.06c
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• pp.35-38
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• 2000

In this paper, we propose a new method to parallelize multidimensional subscript loop with non-uniform distance. A loop comprise most of the computation in a program and the most important source of parallelism. Multidimensional subscript within a loop difficult to determine for distance to be required loop dependence Elimination. Therefore we Propose new methods that is three algorithm to search subscript.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.367-370
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• 1996

This study deals with the motion modeling by the unit motion of robots and the work measurement through classification of robot motions and standardization. The proposed approach is to scrutinize the Predetermined Time Standards(PTS) methods for measurement of manual tasks performed by people and the basic motions for accomplishing that tasks. And then, it constructs the unit motion models as subsets composed with the basic motions. It apply together with movements distance as a time variable, too. These results are used for the work measurements of robots by the unit motion models.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.815-823
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• 2012

In this paper reliability growth model in which the operating time between successive failure is a continuous random variable is proposed. This model is for Burr type XII distribution with two parameters which is discussed in two versions: the order statistics and non-homogeneous Poisson process. The two software reliability measures are obtained. The performance for two versions of the suggested model is tested on real data set by U-plot and Y-plot using Kolmogorov distance.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.40.2-40.2
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• 2019

Measuring distances at cosmological scales is one of the most important, yet most difficult to acquire astronomical quantities, allowing astronomers to determine the expansion rate of the universe. Typically, astronomers have sought to find "standard candles" that have a known intrinsic brightness in order to determine their distance. The most well known standard candles are Type 1a supernova and Cepheid variable stars making the so-called "distance ladder". Here we present a method for determining cosmological distances via light travel-time arguments, which can be extended from nearby sources to very high redshift sources.