• Journal of Conservation Science
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• v.38 no.2
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• pp.87-95
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• 2022

This aimed to species identification and tree-ring dating of wooden elements used in the Myeongjeong-gate of the Changgyeong-palace, Seoul, Korea. Of the 79 wooden elements evaluated, 78 were confirmed to be hard pines and one belonged to Abies spp.. Cores of the wooden elements were collected using a drill for tree-ring dating, and ring-width plots of individual samples were constructed using the TSAP software. The tree-ring dating results for the outermost ring of 58 hard pine wooden elements revealed the following felling dates: early spring of 1604-late fall of 1615, late fall of 1706-early spring of 1707, and late fall of 1828-late fall of 1834. The obtained felling dates of the 1600s and 1800s were found to be consistent with those in the construction and repair records of the Annals of Joseon Dynasty, Gwanghaegun's Diary and Changgyeonggung Yeonggeondogam Uigwe. However, the obtained felling dates of the 1700s were not consistent with those in the construction and repair records. Therefore, additional confirmation of repairs that were not included in the records was possible using tree-ring dating.

• Journal of Korean Institute of Fire Investigation
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• v.2 no.1
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• pp.43-54
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• 2003

• Journal of Korean Institute of Fire Investigation
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• v.1 no.1
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• pp.23-31
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• 2002

• Electronics and Telecommunications Trends
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• v.34 no.1
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• pp.61-74
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• 2019

The capacity of wireless communications has been considered to be restricted by their fundamental limits, which were first formulated by Shannon in 1948. These limits are for the communication environment that is composed of a transmitter and receiver pair. However, there are usually more than one simultaneously communicating pairs in the environment. In such cases, the capacity is not known. Moreover, performance requirements have been diversified with the development of technology. We believe that wireless communication technologies will eventually progress toward limitless connections. Various wireless transmission and access technologies are introduced in order to overcome their limitations.

• Journal of Korean Institute of Fire Investigation
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• v.4 no.1
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• pp.62-69
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• 2004

The purpose of this study on the sheath heater having high occurrence of fires in a small work place because of not having the safety device, was to find out the characteristics required in the field examination of the fires in the courses of investigation. The results of the experiments conducted and reviewed on the basis of the fire cases whose conditions of the ignition possibility were divided into A, E, C and D are as follows: When the sheath heater without safety device is left on the condition of the heat accumulation of which the temperature rapidly rise, and then ignite the inflammables of the surroundings. In such cases, it was characterized that the color change trace appeared even if no short trace was discovered in the power line.

• The Journal of the Petrological Society of Korea
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• v.24 no.2
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• pp.141-147
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• 2015

Using laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), we evaluated the reliability of trace element abundance data measured from the silicate rock references of JR-3, JG-3, JGb-1 and JB-1b using glass discs made by alkali fusion. For 28 elements including rare earth elements, relative standard deviations (RSD) are better than 7% in case when the concentrations of the elements in the rock samples are greater than 10 ppm. However, RSD shows somewhat increased values for the concentrations less than 10 ppm, but never exceeds 25%. Compared with previously reported averages of the compiled abundance data, our data display satisfactory results for the most cases with differences less than 10%. We suggest that LA-ICP-MS analysis using fused glass beads is a reliable, precise and time-saving method of trace element analysis for the silicate rocks spanning from mafic to felsic compositions.