• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.6-11
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• 2013

In this paper, we explain the signal characteristics of HEMP and HEMP protection factors that affect the facilities are analyzed. We find the necessary elements of the physical facilities available for building. Shielding effects were measured by changing frequency and the distance of receiving antenna. Each measured value was compared to U.S. standard and measuring method was simplified. shielding effects were measured by three different conditions of shielding room. Find the difference between forward measurement and reverse measurement and factors which affects the measurement in shielding room.

• Composites Research
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• v.20 no.3
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• pp.55-62
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• 2007

Interfacial evaluation and durability of Jute and Hemp fibers/polypropylene (PP) composites were investigated. Moisture content of various treated conditions were measured by thermogravimetic analyzer (TGA). After boiling water test, mechanical properties and IFSS between Jute, Hemp fibers and PP matrix decreased. On the other hand, work of adhesion increased due to swelled fibril by water. Surface energies of Jute and Hemp fibers before and after boiling water test were obtained using dynamic contact angle measurement. IFSS was not always consistent with thermodynamic work of adhesion. In boiling water case, since Jute and Hemp fibers could be swelled by water, surface area and moisture infiltration space increased. Environmental effect on microfailure modes of Jute or Hemp fibers and Jute or Hemp fibers/PP composites were obtained by observing via optical microscope and by monitoring acoustic emission (AE) events and their AE parameters. After boiling water test, unlike Hemp fiber, microfailure process of Jute fiber could occur due to low tensile strength by swelled fibril. In addition, AE events occurred more and AE amplitude and energy became lower than those of before boiling water test.

• Journal of Satellite, Information and Communications
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• v.8 no.3
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• pp.20-24
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• 2013

In this paper, we introduce a concept of HEMP systems and analyze a shielding effectiveness by varying placements of the antenna elements. Maxwell's equations for the high frequency of the EMP is represented in the LOS. In order to investigate the effects of electromagnetic attenuations, a shielding room was constructed and employed to obtain measured data. Shielding effects were measured by changing frequency and the distance of receiving antenna. Each measured value was compared to U.S. standard and measuring method was simplified. shielding effects were measured by three different conditions of shielding room. Find the difference between forward measurement and reverse measurement and factors which affects the measurement in shielding room.

• Journal of Adhesion and Interface
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• v.7 no.2
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• pp.1-11
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• 2006

Interfacial evaluation of the untreated and treated Jute and Hemp fibers reinforced different matrix polypropylene-maleic anhydride polypropylene copolymer (PP-MAPP) composites were investigated by micromechanical technique and dynamic contact angle measurement. For the statistical tensile strength of Jute and Hemp fibers, bimodal Weibull distribution was fitted better than the unimodal distribution. The acid-base parameter on the interfacial shear strength (IFSS) of the natural fiber composites was characterized by calculating the work adhesion, $W_a$. The effect of alkaline, silane coupling agent on natural fibers were obtained with changing MAPP content in PP-MAPP matrices. Alkaline treated fibers made the surface energy to be higher due to removing the weak boundary layers and thus increasing surface area, whereas surface energy of silane treated Jute and Hemp fibers decreased due to blocked high energy sites. MAPP in the PP-MAPP matrix caused the surface energy to increase due to introduced acid-base sites. Microfailure modes of two natural fiber composites were observed clearly differently due to different tensile strength of natural fibers.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.157-160
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• 2005

The surface energies and acid-base interaction between the untreated and treated Jute or Hemp fibers and different matrix compositions of polypropylene-maleic anhydride polypropylene copolymers (PP-MAPP) were investigated using dynamic contact angle measurement. The contribution of the acid-base property into the interfacial adhesion of the natural fibers/matrix systems were characterized by calculating the work adhesion coming from the acid-base interaction. On the other hand, microfailure mechanism of both single Jute and Hemp fiber bundles were investigated using the combination of single fiber tensile test and acoustic emission. Distinctly different micro failure modes of the different natural fiber/polypropylene systems wet ε observed using optical microscope and determined indirectly by AE and their FFT analysis.

• Journal of Conservation Science
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• v.5 no.2 s.6
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• pp.57-64
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• 1996

Korean Paintings have been drawn on in the main two types of support material - paper and silk. In these things, silk designates picture silk, that of a specially weaved textile for painting since CHO-SUN dynasty, different such as hemp, ramie have been started to use for support material In addition to picture silk. However the structure of hemp and ramie are so close and progue, They are not proper to express the technique of pigments on the back of the paintings. On the other hand, picture silk is efficacious in pigments on the back of the painting with its interval between the strands and translucent textile. As the result, paintings on the silk has many - sided techniques as compared with painting on the papers therfore various devices in conservation have to be considered to deal with the techniques. In this report the focus is on classifying the method of removing the Lining paper according to the several types of expression technique of paintings on the silk.

• Journal of Soil and Groundwater Environment
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• v.19 no.5
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• pp.35-44
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• 2014

In this study, the bio-phytoremediation and phytoremediation technologies were applied to the soils contaminated with total petroleum hydrocarbons (TPH) and heavy metals to evaluate the remediation efficacy from May 2012 to December 2013. Poplar (Populus bonatii Levl.) and Sun Hemp (Crotalaria juncea L.) were selected and planted in phytoremediation practice. These plants were also utilized in the bio-phytoremediation practice, with the addition of earthworm (Eisenia fetida) and petroleum-degrading bacteria (Pseudomonos sp. NKNU01). Furthermore, physiological characteristics, such as photosynthesis rate and maximal photochemical yield, of all testing plants were also measured in order to assess their health conditions and tolerance levels in adverse environment. After 20 months of remedial practice, the results showed that bio-phytoremediation practice had a higher rate of TPH removal efficacy at 30-60 cm depth soil than that of phytoremediation. However, inconsistent results were discovered while analyzing the soil at 100 cm depth. The study also showed that the removal efficiency of heavy metals was lower than that of TPH after remediation treatment. The results from test field tissue sample analysis revealed that more Zinc than Chromium was absorbed and accumulated by the tested plants. Plant height measurements of Poplar and Sun Hemp showed that there were insignificant differences of growth between the plants in remediation plots and those in the control plot. Physiological data of Poplar also suggested it has higher tolerance level toward the contaminated soils. These results indicated that the two testing plants were healthy and suitable for this remediation study.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.42-45
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• 2005

Interfacial evaluation of various combinations of both Flax and Hemp fibers/polypropylene were performed by using micromechanical test and nondestructive acoustic emission (AE). It can be because interfacial adhesion between the natural fiber surface and matrix plays an important role in controlling the overall mechanical properties of polymer composite materials by transferring the stress from the matrix to the fiber. It is necessary to characterize the interphase and the level of adhesion to understand the performance of the composites properly. Microfailure mechanism of single Flax fiber bundles were investigated using the combination of single fiber tensile test and nondestructive acoustic emission. Microfailure modes of the different natural fiber/polypropylene systems were observed using optical microscope and determined indirectly by AE and their FFT analysis.

• Proceedings of the Korean Society of Crop Science Conference
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• 1994.06a
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• pp.52-53
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• 1994

• Sijohaknonchong
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• v.24
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• pp.47-85
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• 2006

One of the famous Korean verses, Sijo 'In hemp clothes in winter(삼동에 베옷 입고)' is in thirty kinds of anthologies and ten kinds of Chinese writings. The major point in literary transmission of this work was the writer. The writer of this verse is Cho Sik(조식) in most anthologies. The writer of this work is recorded as Kil Jae(길재), Kim In-hoo(김인후), Kim Eung-jung(김응정), Lee Mong-gyu(이몽규) or Kim Ryung(김령) in Chinese writings. These people were famous for their studies and virtue, but they did not take office and retired from the world until they die. They were faithful to their principles serving their kings, though the country had wanted them to take a position in the government. Even though they did not in government service, they left some anecdotes and stories of lamentation after hearing their king's death. Because these stories and anecdotes can be easily connected with 'In hemp clothes in winter' which is about mourning over death of a king, they were known as the writer of this poem. Especially, their offsprings, juniors and followers often wrote these people as the writer of this work to represent their honor. Throughout the studies of several literary documents, this poem is written by Kim Eung-Jung, who lived in Kangjin(강진) in Jeonla province(전라도) and did not take office in all his life. He made this poem when he had heard the King Myoungjong(명종)'s death. Various transmission of literary documents with the records about 'In hemp clothes in winter' have a significance that can show the aspects of noble men's acceptance and transmission of Sijo.