• Proceedings of the Korean Geotechical Society Conference
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.1154-1160
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• 2009

Cut slope failure is happened in various form by several causes. In this study, we searched causes of cut slope failure shortly, and we made a study of slope failure by excessive under cut. Under cutting slope does to add unstability. Thereby, cut slope failure can be happened on a large scale.

• Corrosion Science and Technology
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• 제9권1호
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• pp.34-38
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• 2010

Electrochemical study on cut edge corrosion of prepainted Zn coated (GI) and 55%Al-Zn coated (GL) steels has been performed in wet-dry cyclic conditions. Maximum width of delaminated polymer coating from the cut edge for GI and GL specimens was evaluated under wet-dry cyclic conditions. The cyclic tests were carried out for 1000 h by changing of relative humidity, where the salt of NaCl was deposited on the specimen every 48 h. The cut edge corrosion test under NaCl deposit indicated that the delamination of the GL specimen progresses at a higher rate than the GI. The electrochemical corrosion monitoring was also performed under condition of alternate exposure to immersion in NaCl solution and drying at 60%RH and $25^{\circ}C$. On the basis of the results of the delamination tests and electrochemical measurements, the mechanism of cut edge corrosion for GI and GL were discussed.

• Journal of the Korean Society of Tobacco Science
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• 제27권2호
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• pp.201-206
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• 2005

In this work, we studied the effects of the moisture contents of cut tobacco on loose end of cigarettes. The loose end of the cigarette groups decreased with the increase of moisture contents of the cut tobacco and especially the loose end of A and C groups decreased to $31\%\;and\;52\%$ with the increase of $1\%$ moisture contents. $A-13.5\%\;and\;B-14.0\%\;and\; C-14.0\%$ moisture samples showed the increase of the weight ratio of cut tobacco over 1.4mm cut length but the decrease under 1.4mm cut length. We concluded that the main reasons were regarded to reduction of small fragment tobaccos caused by increase of moisture contents and exception of air-suction transport of tobaccos to cigarette making machine. In spite of the moisture increase of cut tobaccos under fixed EPD(encapsulated pressure drop), the hardness of Band C sample groups were maintained constantly except A group. This result means that under fixed EPD, the weight of cut tobacco in cigarette rods increases to compensate the reduction of pressure drop by moisture increase of cut tobaccos.

• Food Science and Preservation
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• 제22권1호
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• pp.154-157
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• 2015

To maintain the freshness and to prevent browning of cut Kimchi cabbages, the effect of the cutting process using a ceramic knife under $N_2$ blowing on the quality of the cut Kimchi cabbages was investigated. Kimchi cabbages cut with a ceramic knife under $N_2$ gas blowing conditions (NC) were stored at $5^{\circ}C$ for 7 days, and their weight reduction ratio and the browning degree and appearance were compared with those of the control treatment samples (OS; cut with a stainless steel knife under normal air, OC; cut with a ceramic knife under normal air). The weight reduction ratios were 0.07~0.13%, and the NC treatment showed the lowest reduction ratio among all the treatments (p<0.05). The Hunter L values increased, but the a and b values decreased after 5-day storage in all the treatments. The NC treatment had higher L values but lower a and b values than the OS and OC treatments. The browning degrees by Hunter color value, PPO activity, and appearances were the least in the NC treatment (p<0.05). The cutting process with a ceramic knife under $N_2$ blowing could be applied to the cutting of vegetable products and for minimal fruit processing.

• Journal of the Korean Society of Tobacco Science
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• 제14권1호
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• pp.57-65
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• 1992

The quality of cut tobacco will be deteriorated due to weather conditions such as temperature and relative humidity, when shipping and long term storaging. The change of equilibrium moisture contents in cut tobacco were under influence of relative humidity and temperature but not humectants. Therefore internal packing materials are necessary for cut tobacco to maintain initial quality, including taste, flavour and musty smell during shipping or storaging. When packing cut tobacco for shipping or long term storaging, desiralbe packing density was 200/$m^2$, For the long term storage under R.H 90% and 3$0^{\circ}C$, polyethylene film thickness suitable for packing material are above 100$\mu$, which resulted in 42days of shelf life.

• Proceedings of the Korean Geotechical Society Conference
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.273-280
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• 2001

In order to evaluate the stability of railway cut-slope under rainfall, explanatory variables and subordinate variables were selected for multivariate analysis. Furthermore the site which had occurred failure due to rainfall was investigated, and by executing multivariate analysis for 121 cases, critical rainfall was defined by the case that had high value of correlation factor. The 0.3 square value of maximum hourly rainfall during 24 hours before failure caused the collapse of railway cut-slope and could be used to estimate the stability of railway cut-slope. From the result of application to a collapse example, the evaluaton method by critical rainfall curve is satisfactory.

• Elastomers and Composites
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• 제36권4호
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• pp.255-261
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• 2001

This study was related with the effect of elevated temperature on the tensile strength of edge-cut samples. There was a different tensile strength behavior of uncut samples and pre-cut samples under different test temperatures. Tensile strength of uncut sample decreases with increasing test temperature. When pro-cut size(C) is larger than critical cut size($C_{cr}$), tensile strength or pre-cut specimen at $80^{\circ}C$ is higher than that of pre-cut specimen at room temperature (RT). Test specimens under $80^{\circ}C$ condition exhibited more secondary cracks at the crack tip region compared to room temperature conditions. However, secondary cracks of pre-cut specimens are not clearly developed at $110^{\circ}C$. Differences in tensile strength induced by different test temperature seem to be responsible for the strain-induced crystallization and micro-cracking patterns.

• Steel and Composite Structures
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• 제34권1호
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• pp.53-73
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• 2020

A novel all-steel miniature bar-type structural fuse (MBSF) with cold formed bolted connections is developed in this study, which consists of a central energy dissipation core cut from a smooth round bar, an external confining tube and nuts. Three types of cross sections for the central energy dissipation core, i.e., triple-cut, double-cut and single-cut cross sections, were studied. Totally 18 specimens were axially tested under either symmetric or asymmetric cyclic loading histories, where the parameters such as cut cross sectional area ratio, length of the yielding portion and cross sectional type were investigated. Numerical simulation of 2 representative specimens were also conducted. An analytical model to evaluate the bending failure at the elastic portion was proposed, and a design method to avoid this failure mode was also presented. The experimental results show that the proposed MBSFs exhibit satisfactory hysteretic performance under both the two cyclic loading histories. Average strain values of 8% and 4% are found to be respectively suitable for designing the new MBSFs as the ultimate strain under the symmetric and asymmetric cyclic loadings.

• Transactions of the Korean Society of Automotive Engineers
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• 제21권2호
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• pp.45-54
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• 2013

In this paper, a theoretical weight-reduction method was suggested to substitute an underframe material of a box-type bodyshell having cut-outs with an alternative light-weight material. To utilize the material substitution method previously developed for a box-type hybrid bodyshell not having cut-outs, we derived a box-type baseline model without cut-outs which is similar to the stiffness condition of a box-type bodyshell having cut-outs. To do this, the thicknesses of roof and walls of the baseline model were determined such that the deflection of the baseline model under a distributed vertical load condition is equal to the sum of the theoretical section deflections of the original box model with cut-outs. Next, to derive a hybrid bodyshell by under-frame material substitution, the material substitution method for a box-type hybrid bodyshell without cut-outs was applied to the box-type baseline model. Finally, we compared the FE simulation results of the derived hybrid bodyshells having cut-outs for various materials with the theoretical results of the suggested method, and we obtained their good correlations.

• The Korean Journal of Health Service Management
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• 제11권2호
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• pp.105-115
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• 2017

Objectives : The aim of this study was to suggest the optimal cut off for best, very good, good, slightly bad, and bad grades. Methods : The subjects were recruited from 4 areas of South Korea and 487 questionnaires were analyzed. The nominal and continuous self-rated health questions were used to reveal the optimal cut off and the Short Form-12 Health Survey questionnaire (SF-12) was additionally used. Frequency, Pearson's correlation coefficient, and ROC-curve analysis were used; the significance level was <.05. Results : Subjects assigned 15(3.1%), 90(18.5%), 237(48.7%), 130(26.7%), and 15(3.1%) to best, very good, good, slightly bad and bad groups respectively. The self-rated health score was associated with total Component (r=.563, p<.001), Physical Component (r=.520, p<.001) and Mental Component of SF-12 (r=.303, p<.001). The optimal cut off was 80.5, 70.5, 53.5, and 40.5 for best, very good or more, good or more, and under slightly bad respectively and area under curve was 0.898, 0.908, 0.945, and 0.908 accordingly. Conclusions : This study suggests that the self-rated health score and grade could be integrated with the optimal cut off.