• Fibers and Polymers
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• v.5 no.3
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• pp.187-197
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• 2004

The compressive and flexural properties of hemp fiber reinforced concretes (FRC) were examined in this paper. Natural hemp fiber was mixed using dry and wet mixing methods to fabricate the FRC. Mechanical properties of the FRC were investigated. The main factors affecting compressive and flexural properties of the FRC materials were evaluated with an orthogonal test design. Fiber content by weight has the largest effect. The method for casting hemp FRC has been optimised. Under the optimum conditions, compressive strength increased by 4 %, flexural strength increased by 9 %, flexural toughness increased by 144 %, and flexural toughness index increased by 214 %.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.6
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• pp.1172-1179
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• 2010

Since HEMP has the very short rising time and propagates widespreadly with several tens of kV/m, it threatens most of systems in its cover range. Therefore, it is important to research coupling mechanism into systems and establish countermeasures for the HEMP to protect systems effectively. This paper analyzed characteristics and trends of currents to be induced at the load of a line which is located over ground with different conditions such as polarization, incidence angle, line length and height etc. We applied double exponential waveform as the HEMP shape and used BLT method to analyze the coupling route into the line. Also, we compared the simulation data of chain matrix modeling to verify reliability of BLT modeling. In the result, two data is almost agreed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.5
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• pp.15-19
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• 2009

Ammonia soaking treatment was introduced for hemp woody core pretreatment to increase enzymatic saccharification of polysaccharides. Portions of the xylan, cellulose, and lignin were removed by aqueous ammonia soaking, which improved the enzymatic saccharification of cellulose and xylan. Following ammonia soaking, 37% ($50^{\circ}C$-6 day treatment) to 61% ($90^{\circ}C$-16 h treatment) of the cellulose was converted to glucose and 33% ($50^{\circ}C$-6 day treatment) to 48% ($90^{\circ}C$-16 h treatment) of the xylan to xylose. Cellulose responded better to enzymatic saccharification than did xylan after the ammonia soaking treatment. Aqueous ammonia soaking pretreatment was more effective than electron beam irradiation for increasing enzymatic saccharification of xylan and cellulose in hemp woody core.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.6
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• pp.154-163
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• 2015

Because of acute or chronic intoxication by carbon disulfide, viscose rayon industry is strictly subjected to environment regulatory approval. Recently, non-wood fibers are frequently considered as a raw materials for the manufacture of specialty paper for the higher physical strength and functionality. Among the non-wood fibers, hemp bast fiber is one of the most widely used materials in viscose rayon yarn industries. In this study, the handsheet for manufacturing the viscose rayon yarn was prepared with wood pulp fibers and hemp bast fibers. The proper mixing ratio of wood fibers and hemp bast fibers with dry-strength agent and nano-celluloses was analysed in terms of physical and mechanical strength of sheet for viscose rayon yarn. The papermaking conditions for high mechanical strength of sheet were obtained by mixing the SwBKP and HwBKP fibers with freeness level of 200 mL CSF. The dual polymer system by controlling the addition ratio of PVAm and anionic PAM was also important. The addition of nano-cellulose into wet-end furnishes increased the physical strength of sheet, and improved the paper structure for the production of viscose rayon yarn.

• The Research Journal of the Costume Culture
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• v.13 no.5 s.58
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• pp.729-742
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• 2005

This paper studied the ban on 'Po[포]', including hemp and ramie, on the basis of Joseon Wangcho Silok (the True Record of Joseon Dynasty). Po is the important point which can help to understand the people's life related with clothing. This paper showed that in the early years of the Joseon Dynasty, the state had forced kinds of bans on some fabrics many times. Among the bans of the fabrics-making the main part was the bans on Po, along with rice, used as money in those days. The state had on Po enacted on the policy to intend to promote paper money circulation more widely. However, people didn't want to use paper money. The reason why cloth could be practical and functional as a kind of currency was that people could make clothes with it at any time while they used it as money. People avoided using paper money that could not be used in that way, and so did public officials. At that time, Po that was generally used as money was the hemp of five warp threads. The measurement of the hemp in 7chi[촌; a Korean inch] by 35chok[척] and 32cm by 16m by modern metric. It also showed that it has been thought that the blended fabrics are the fabrics that were made of raw silk-threads and cotton threads as warp and weft respectively. However, the fact that there is a record of 'Jeo Ma Gyo Jik Po[저마교직포의]'(blended fabrics and clothes made of ramie and hemp) and there appear the new proofs of the fieldwork investigation shows that the concept of blended fabrics might be various or changeable as time passed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.67-74
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• 2004

This study was carried out to investigate the characteristics of handsheets made from nonwoody New-Zealand hemp (Phormium tenax) fibers that was not used before in Korea. The results were as follows : 1. Physical properties of bleached phormium fiber were satisfactory for handsheet forming. Specially, tensile strength was improved by adding bleached phormium fiber. 2. Opacity of handsheet with phormium pulp was fine, therefore it can be useful fiber to improve opacity of light-weight printing paper. 3. Filler retention rate was improved when phormium pulp was added, while drainage time was increased. 4. Phormium fiber has good characteristics as pulp for paper manufacture. So it can be valuable non-wood fiber resource if drainage problem is solved.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.10a
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• pp.389-395
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• 2011

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.293-300
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• 2011

• Polymer(Korea)
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• v.39 no.1
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• pp.46-55
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• 2015

There is a limit for deforestation in order to keep the environmental cycle undisturbed. The heart of the paper is to replace the wood to a maximum extent to obtain a sustainable environment. This research aims at new natural composites in which treated hemp fiber used as reinforcement, synthetic cellulose used as particulate to improve the adhesion between matrix - fiber interface and Epoxy LY556 acted as matrix fabricated by hand layup technique. The density, water absorption, tensile properties, impact strength, hardness, flexural properties and compressive properties have been evaluated under ASTM standards and compare the results with existing materials such as wood, aluminium, etc., The composite hemp fiber reinforced polymer (HFRP) could be exploited as an effective replacement for wood and it would be suitable for automotive applications by comparing results.

• 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.